Animal Sciences and Industry Faculty Research and Publications

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Open Access
Anti-inflammatory salicylate treatment alters the metabolic adaptations to lactation in dairy cattle
(2013-07-15) Farney, Jaymelynn K.; Mamedova, Laman K.; Coetzee, Johann F.; KuKanich, Butch; Sordillo, Lorraine M.; Stoakes, Sara K.; Minton, J. Ernest; Hollis, Larry C.; Bradford, Barry J.
Adapting to the lactating state requires metabolic adjustments in multiple tissues, especially in the dairy cow, which must meet glucose demands that can exceed 5 kg/day in the face of negligible gastrointestinal glucose absorption. These challenges are met through the process of homeorhesis, the alteration of metabolic setpoints to adapt to a shift in physiological state. To investigate the role of inflammation-associated pathways in these homeorhetic adaptations, we treated cows with the nonsteroidal anti-inflammatory drug sodium salicylate (SS) for the first 7 days of lactation. Administration of SS decreased liver TNF-α mRNA and marginally decreased plasma TNF-α concentration, but plasma eicosanoids and liver NF-κB activity were unaltered during treatment. Despite the mild impact on these inflammatory markers, SS clearly altered metabolic function. Plasma glucose concentration was decreased by SS, but this was not explained by a shift in hepatic gluconeogenic gene expression or by altered milk lactose secretion. Insulin concentrations decreased in SS-treated cows on day 7 compared with controls, which was consistent with the decline in plasma glucose concentration. The revised quantitative insulin sensitivity check index (RQUICKI) was then used to assess whether altered insulin sensitivity may have influenced glucose utilization rate with SS. The RQUICKI estimate of insulin sensitivity was significantly elevated by SS on day 7, coincident with the decline in plasma glucose concentration. Salicylate prevented postpartum insulin resistance, likely causing excessive glucose utilization in peripheral tissues and hypoglycemia. These results represent the first evidence that inflammation-associated pathways are involved in homeorhetic adaptations to lactation.the transition from late pregnancy to lactation is a time of great physiological stress, especially for the dairy cow. The decline in feed intake that accompanies parturition, coupled with the rapid increase in energy requirements during lactogenesis, requires a dramatic shift in nutrient fluxes to release stored nutrients and direct them to the mammary gland. This programmed shift in metabolic setpoints is an archetypal example of homeorhesis, defined as the “coordinated changes in metabolism of body tissues necessary to support a physiological state” (4).Mechanisms underlying homeorhetic adaptions to lactation have been described to some extent. The somatotropic axis is decoupled during this time, resulting in dramatic elevations of plasma growth hormone concentrations without the expected rise in insulin-like growth factor 1 secretion (11, 51). Likewise, insulin sensitivity declines substantially from late gestation (5, 48). These endocrine shifts are critical for promoting the mobilization of stored nutrients and sparing glucose for use by the mammary gland. This conservation of glucose is particularly important in ruminants. The microbes that inhabit the rumen ferment most dietary carbohydrate to volatile fatty acids, leaving very little glucose to be absorbed in the small intestine. As a result, lactating cows absorb almost no glucose from the gastrointestinal tract and must synthesize as much as 5 kg of glucose in the liver daily (2).The homeorhetic adaptations that allow cows to increase milk production to 40 kg/day within days after parturition can stress the metabolic system. Rapid lipolysis can increase plasma nonesterified fatty acid (NEFA) concentrations by as much as 10-fold within a few days after parturition (21), and both hypoglycemia and hypocalcemia are common, as nutrients are drawn into the mammary gland. Ketosis and fatty liver (FL) are common metabolic diseases that result during this time; in fact, nearly 90% of all metabolic diseases in dairy cattle occur during the first 4 wk of the 305-day lactation (24).Despite their reliance on mobilized lipid as an energy source, dairy cattle entering lactation with greater adipose mass are at greater risk of developing metabolic diseases (34). It has become clear in the past decade that animals with excessive adiposity exhibit a low-grade inflammation (23), suggesting that perhaps inflammation underlies metabolic disturbances in obese dairy cows. In support of this hypothesis, cows with moderate or severe FL have increased levels of the inflammatory cytokine TNF-α (41). Inflammatory cytokines cause myriad metabolic changes in dairy cattle, including anorexia, lipomobilization, impaired insulin sensitivity, and reduced milk yield (7, 26, 27), all of which are associated with FL and ketosis. Furthermore, daily injection of TNF-α for 7 days increased liver triglyceride content independent of effects on feed intake, and this effect was accompanied by changes in hepatic gene expression consistent with both inflammation and a shift from fatty acid oxidation to triglyceride synthesis (8).These recent findings suggest that exogenous inflammatory agents are sufficient to induce metabolic dysfunction. Whether inflammation is a necessary causative factor in the natural progression of bovine FL and ketosis, however, remains unclear. To address this broad question, we used the nonsteroidal anti-inflammatory drug (NSAID) sodium salicylate (SS). Sodium salicylate is a weak inhibitor of cyclooxygenase (COX)-1 and COX-2 (31), and its probable mode of action is that it inhibits phosphorylation of the NF-κB inhibitor IκB-α (53). Phosphorylation of IκB results in its degradation, allowing NF-κB to be released for translocation into the nucleus and subsequent activation of an inflammatory transcription program (3). The specific hypothesis for this study was that SS would slow liver triglyceride accumulation, promote gluconeogenesis, and limit metabolic disease in dairy cows entering lactation. In contrast, our findings suggest that inflammatory signals may contribute to homeorhetic adaptations to lactation, especially regulation of glucose metabolism and modulation of lipolysis and ketogenesis as animals return to positive energy balance.
Open Access
Evaluating the impact of maternal vitamin D supplementation: I. Sow performance, serum vitamin metabolites, and neonatal muscle characteristics
Flohr, Joshua R.; Woodworth, Jason C.; Bergstrom, J. R.; Tokach, Michael D.; Dritz, Steven S.; Goodband, Robert D.; DeRouchey, Joel M.; jwoodworth; mtokach; dritz; goodband; jderouch; Woodworth, Jason C.; Tokach, Michael D.; Dritz, Steven S.; Goodband, Robert D.; DeRouchey, Joel M.
In Exp. 1, 56 gestating sows (PIC 1050; 35 d postinsemination) were used in a 30-d trial to determine serum 25(OH)D-3 response to increasing concentrations of dietary vitamin D3. Sows were randomly allotted to 1 of 7 dietary D3 treatments (200, 800, 1,600, 3,200, 6,400, 12,800, or 25,600 IU of added D3 per kilogram of complete diet) with 8 sows per treatment. Increasing D-3 increased (quadratic; P < 0.001) serum 25(OH)D-3 with the response depicted by the prediction equation: serum 25(OH) D3, ng/mL = 35.1746 + (0.002353 x dietary D-3, IU/d)- (0.0000000156 x dietary D3, IU/d(2)). In Exp. 2, 112 sows and their litters were used to determine the effects of dietary vitamin D regimen on sow performance, subsequent preweaning pig performance, neonatal bone and muscle characteristics, and serum vitamin metabolites. Sows were allotted to 1 of 4 dietary treatments 3 to 5 d following breeding: 800, 2,000, or 9,600 IU of D-3 per kilogram of the diet or 50 mu g of 25(OH) D-3 (2,000 IU of D-3 equivalent from Hy- D, DSM Nutritional Products, Parsippany, NJ) per kilogram of diet. There were 25 to 27 sows per treatment. Increasing dietary D-3 increased (linear, P = 0.001) serum 25(OH) D-3 of sows on d 100 of gestation, at farrowing, and at weaning. Increasing D-3 in sow diets increased piglet serum 25(OH)D-3 at birth (linear, P = 0.001) and weaning (quadratic, P = 0.033). Sows fed 50 mu g of 25(OH)D-3/kg had intermediate (P < 0.004) serum 25(OH)D-3 concentrations on d 100 of gestation, at farrowing, and at weaning compared with sows fed 2,000 IU of D-3/kg and sows fed 9,600 IU of D3/kg. Pigs from sows fed 50 mu g of 25(OH) D3/ kg had greater serum 25(OH)D-3 compared with pigs from sows fed 2,000 IU of D-3/kg, but at weaning, serum 25(OH)D-3 concentrations were similar. Also, pigs from sows fed 9,600 IU of D-3/kg had greater (P = 0.011) serum 25(OH) D3 at birth and weaning compared with pigs from sows fed 50 mu g of 25(OH) D-3/kg. Maternal performance, litter characteristics, neonatal bone ash content, and neonatal muscle fiber characteristics were largely unaffected by the dietary vitamin D treatments. Overall, D3 and 25(OH) D3 are both useful at increasing serum 25(OH)D-3 concentrations, but more D3 (on an equivalent IU basis) is needed to achieve similar serum 25(OH)D-3 responses compared with feeding 25(OH)D-3. Concentration of maternal vitamin D supplementation in lactation impacted milk transfer of the vitamin more so than the form of the vitamin, as evidence by the weaned pig serum 25(OH)D-3 concentrations.
Open Access
Evaluating the removal of pigs from a group and subsequent floor space allowance on the growth performance of heavy-weight finishing pigs
Flohr, Joshua R.; Tokach, Michael D.; DeRouchey, Joel M.; Woodworth, Jason C.; Goodband, Robert D.; Dritz, Steven S.; mtokach; jderouch; jwoodworth; goodband; dritz; Tokach, Michael D.; DeRouchey, Joel M.; Woodworth, Jason C.; Goodband, Robert D.; Dritz, Steven S.
A total of 1,092 finishing pigs (initially 36.3 kg) were used in a 117-d study to evaluate the impact of initial floor space allowance and removal strategy on the growth of pigs up to 140 kg BW. There were 4 experimental treatments with 14 pens per treatment. The first treatment provided 0.91 m(2) per pig (15 pigs/pen). The other 3 treatments initially provided 0.65 m(2) per pig (21 pigs/pen) with 3 different removal strategies. The second treatment (2:2:2) removed the 2 heaviest pigs from pens on d 64, 76, and 95 when floor space allowance was predicted to be limiting. Treatment 3 (2:4) removed the 2 heaviest pigs on d 76 and the 4 heaviest pigs on d 105. Treatment 4 (6) removed the heaviest 6 pigs on d 105. All pigs remaining in pens after removals were fed to d 117. Overall (d 0 to 117), pigs initially provided 0.91 m(2) of floor space had increased (P < 0.05) ADG compared to pigs in pens on the 2: 4 or 6 removal strategy, but ADG was not different compared with pigs on the 2:2:2 removal strategy. Total BW gain per pen was greater (P < 0.05) for pens initially stocked at 0.65 m(2) compared to pens initially stocked at 0.91 m(2). Feed usage per pen was less (P < 0.05) for pens initially stocked at 0.91 m(2) compared to pens initially providing 0.65 m(2) of floor space and on removal strategies; however, feed usage per pig was greater (P < 0.05) for pigs initially stocked at 0.91 m(2) compared to pigs initially stocked at 0.65 m(2) and on removal strategies. Feed usage, on a pig or pen basis, was less (P < 0.05) for pigs on the 2: 2: 2 removal strategy compared to pigs on the 2:4 or the 6 removal strategy. Income over feed and facility cost (IOFFC) was less (P < 0.05) for pigs initially provided 0.91 m(2) compared to pigs initially provided 0.65 m(2) and on removal strategies. Also, IOFFC was less (P < 0.05) for pigs on the 2:2:2 compared to the 2:4 and 6 removal strategies. In conclusion, increasing the floor space allowance or the time points at which pigs are removed from the pen improved the growth of pigs remaining in the pen; however, IOFFC may be reduced because fewer pigs are marketed from each pen (pigs stocked at 0.91 m(2) throughout the study) or from reducing total weight produced (2:2:2 removal strategy).
Open Access
Effects of anabolic implants and ractopamine-HCl on muscle fiber morphometrics, collagen solubility, and tenderness of beef longissimus lumborum steaks
Ebarb, Sara M.; Phelps, Kelsey J.; Drouillard, James S.; Maddock-Carlin, K. R.; Vaughn, M. A.; Burnett, D. D.; Noel, Jere A.; Van Bibber-Krueger, Cadra L.; Paulk, C. B.; Grieger, David M.; Gonzalez, John M.; johngonz; dgrieger; jdrouill; Gonzalez, John M.; Grieger, David M.; Drouillard, James S.
The objective of this study was to examine the effects of growth-promoting technologies (GP) and postmortem aging on longissimus lumborum muscle fiber cross-sectional area (CSA), collagen solubility, and their relationship to meat tenderness. Two groups of black-hided crossbred feedlot heifers (group 1: n = 33, initial BW 430 +/- 7 kg; group 2: n = 32, initial BW 466 +/- 7 kg) were blocked by BW and assigned to 1 of 3 treatments consisting of: no implant and no ractopamine hydrochloride (CON; n = 21); implant, no ractopamine hydrochloride (IMP; n = 22); implant and ractopamine hydrochloride (COMBO; n = 22). Heifers that received an implant were administered an implant containing 200 mg trenbolone acetate and 20 mg estradiol on d 0 of the study, and heifers in the COMBO group received 400 mg.head(-1).d(-1) of ractopamine hydrochloride for 28 (Group 1) or 29 d (Group 2) at the end of 90-(Group 1) or 106-d (Group 2) feeding period. Following harvest, strip loins were collected and further fabricated into 5 roasts for postmortem aging (DOA) periods of 2, 7, 14, 21, or 35 d. After aging, Warner-Bratzler shear force (WBSF), muscle fiber CSA, and collagen solubility were measured. There was no treatment x DOA interaction for WBSF (P = 0.86), but treatment and DOA impacted WBSF (P < 0.01). Over the entire aging study, COMBO steaks had greater (P < 0.01) shear force values when compared to CON steaks. The IMP steaks tended to have decreased (P = 0.07) shear force when compared to the COMBO steaks, but did not differ (P = 0.11) from CON steaks. The IMP and COMBO treatments had increased type IIA fiber CSA when compared to CON (P < 0.01). When compared to each other, the IMP and COMBO type IIA fiber CSA did not differ (P = 0.76). Type I and IIX fiber CSA tended to be greater than CON for IMP and COMBO treatments (P < 0.10). There was no treatment x DOA interaction for all collagen measures (P > 0.33). Collagen amounts were not impacted by GP treatment (P > 0.72), but DOA increased the concentration of soluble collagen (P = 0.04). Fiber CSA of all fiber types were positively correlated (P < 0.05; r = 0.21 to 0.28) with WBSF only on d 2 of aging, while soluble collagen amount tended to negatively correlate with WBSF on d 7 and 14 of aging (P < 0.10; r = -0.24 and -0.23, respectively). Administration of GP during heifer finishing resulted in greater steak WBSF over 35 d of aging, which was not due to collagen characteristics and only minimally affected by fiber CSA.
Open Access
Stability of commercial phytase sources under different environmental conditions
De Jong, J. A.; DeRouchey, Joel M.; Tokach, Michael D.; Dritz, Steven S.; Goodband, Robert D.; Woodworth, Jason C.; Jones, Cassandra K.; Stark, Charles R.; jderouch; mtokach; dritz; goodband; jwoodworth; jonesc; crstark; DeRouchey, Joel M.; Tokach, Michael D.; Dritz, Steven S.; Goodband, Robert D.; Woodworth, Jason C.; Jones, Cassandra K.; Stark, Charles R.
A 300-d study was conducted to evaluate storage stability of 4 commercially available phytase products under varied environmental conditions. Products used were: 1) Quantum Blue G (AB Vista, Plantation, FL), 2) Ronozyme Hi Phos GT (DSM Nutritional Products, Parsippany, NJ), 3) Axtra Phy TPT (Dupont, Wilmington, DE), and 4) Microtech 5000 Plus (Guangdong Vtr Bio-Tech Co., Ltd., Guangdong, China). Products were stored as pure forms, in a vitamin premix, or a vitamin trace mineral (VTM) premix. Pure products were stored at -20 degrees C, 4 degrees C, 22 degrees C, or 35 degrees C (75% humidity). Vitamin and VTM premixes were stored at 22 degrees C or 35 degrees C (75% humidity). Samples were stored in open-topped paper bags and sampled on d 30, 60, 90, 120, 210, and 300. Stability was determined as the amount of residual phytase activity (% of initial) at each sampling point. For the pure forms, all interactive and main effects of phytase product, time, and storage temperature were significant (P < 0.05). From d 30 to 300, products had similar reductions in phytase activity at the 3 highest temperatures; however, Quantum Blue G, Ronozyme HiPhos GT, and Axtra Phy TPT had reduced (P < 0.05) phytase activity as compared to Microtech 5000 at -20 degrees C. In general, as storage time increased, residual phytase activity decreased (P < 0.05) regardless of product and storage temperature. When product was stored at 4 degrees C and 22 degrees C, phytase activity was greater than that of product stored at -20 degrees C or 35 degrees C, and Microtech 5000 Plus had greater (P < 0.05) stability regardless of time and temperature as compared to the other 3 products. For vitamin and VTM premixes, a time x temperature x product interaction (P < 0.05) was observed. When stored at 22 degrees C, Axtra Phy TPT and Microtech 5000 Plus had reduced residual phytase activity (P < 0.05) when compared to the other 2 products; however, when stored at 35 degrees C Axtra Phy had even further reduced (P < 0.05) activity than the other 3 products regardless of which form the products were stored in. From d 30 to 300 Axtra Phy TPT and Microtech 5000 Plus had the lowest (P < 0.05) residual phytase activity when compared to the others regardless of storage form or temperature. Phytase products stored in VTM premix had decreased (P < 0.05) residual phytase activity when compared to pure products and vitamin premixes. In conclusion, phytase stored for longer than 90 to 120 d, at both high (35 degrees C) and low (-20 degrees C) temperatures when in pure form or as a VTM premix had reduced residual phytase activity.
Open Access
Gonadotropin-releasing hormone increased pregnancy risk in suckled beef cows not detected in estrus and subjected to a split-time artificial insemination program
Hill, Scott L.; Grieger, David M.; Olson, K. C.; Jaeger, John R.; Dahlen, C. R.; Crosswhite, M. R.; Pereira, N. N.; Underdahl, S. R.; Neville, B. W.; Ahola, J.; Fischer, M. C.; Seidel, G. E.; Stevenson, Jeffrey S.; jss; jrjaeger; kcolson; Stevenson, Jeffrey S.; Jaeger, John R.; Olson, KC
We hypothesized that GnRH would increase pregnancy risk (PR) in a split-time AI program for cows in which estrus was not detected. A total of 1,236 suckled beef cows at 12 locations in 3 states (Colorado, Kansas, and North Dakota) were enrolled. Before applying the fixed-time AI program, BCS was assessed. Cows were treated on d -7 with a progesterone insert concurrent with 100 mu g GnRH and on d 0 with 25 mg PGF(2 alpha) plus removal of the insert. Estrus-detection patches were affixed to cows at insert removal. Estrus was defined to have occurred when an estrus-detection patch was >50% colored (activated). Cows in estrus by 65 h (n = 758; 61.3% of all cows) were randomly allocated to 2 treatments: 1) 100 mu g GnRH and early + GnRH (E+G; n = 373) or 2) AI only at 65 h (early -no GnRH [E-G]; n = 385). The remaining cows were randomly allocated to 2 treatments: 1) 5(L+G; n = 252) or 2) AI only at 84 h (late no GnRH [L-G]; n = 226). Pregnancy was determined 35 d after AI via transrectal ultrasound. Pregnancy risk did not differ (P = 0.68) between E+G and E-G cows (61.9 vs. 60.4%, respectively). Conversely, for cows inseminated at 84 h, PR was greater (P = 0.01) in cows that received GnRH (L+G) compared with their herd mates not receiving GnRH (L-G; 41.7 vs. 30.8%, respectively). Of those cows not detected in estrus by 65 h, 42.1% were detected by 84 h, for a total expression of estrus by all cows of 77.6%. Administration of GnRH increased (P < 0.01) PR in cows not detected in estrus by 84 h (+ GnRH = 33.4% [n = 146] vs. no GnRH = 15.0% [n = 128]) but had no effect in cows expressing estrus by 84 h (+ GnRH = 65.3% [n = 103] vs. no GnRH = 61.7% [n = 97]). Neither estrus expression by 65 or 84 h nor PR was influenced by BCS, parity, or days postpartum at AI. Cows had greater PR when they had been detected in estrus before AI, and PR was improved by administration of GnRH at 65 h after insert removal in cows that were not detected in estrus and inseminated at 84 h.
Open Access
The progression of deoxynivalenol-induced growth suppression in nursery pigs and the potential of an algae-modified montmorillonite clay to mitigate these effects
Frobose, Hyatt L.; Erceg, Jake A.; Fowler, S. Q.; Tokach, Michael D.; DeRouchey, Joel M.; Woodworth, Jason C.; Dritz, Steven S.; Goodband, Robert D.; goodband; dritz; jwoodworth; jderouch; mtokach; Goodband, Robert D.; Dritz, Steven S.; Woodworth, Jason C.; DeRouchey, Joel M.; Tokach, Michael D.
Two experiments were conducted to characterize the progression of deoxynivalenol (DON)-induced growth suppression and to investigate algae-modified montmorillonite clay (AMMC) as a means to alleviate the effects of DON in nursery pigs. In both experiments, naturally DON-contaminated wheat was used to produce diets with desired DON levels. In Exp. 1, 280 barrows and gilts (10.0 +/- 0.2 kg BW) were used in a 28-d experiment arranged in a 2 x 2 + 1 factorial design with 8 replicates per treatment. The 5 treatments consisted of 2 positive control (PC) diets with DON below detection limits and with or without 0 or 0.50% AMMC and 3 negative control (NC) diets with 5 mg/kg of DON and containing 0, 0.25, or 0.50% AMMC. No DON x AMMC interactions were observed. Overall, pigs fed DON had decreased (P < 0.001) ADG and final BW regardless of AMMC addition. Feeding DON-contaminated diets elicited the most severe depression (P < 0.001) in ADFI and G:F from d 0 to 3, remaining poorer overall (P < 0.01) but lessening in severity as exposure time increased. Pigs fed DON diets had greater (P < 0.05) within pen BW variation (CV) on d 28. Although the addition of 0.50% AMMC to diets restored (P < 0.05) ADFI from d 14 to 21 to levels similar to the PC, no other differences were observed for AMMC inclusion. In Exp. 2, 360 barrows (11.4 +/- 0.2 kg BW) were used in a 21-d experiment with 9 dietary treatments arranged in a 3 x 3 factorial design with DON and AMMC inclusion as main effects. There were 8 replicate pens per treatment. Treatments consisted of 3 PC diets without DON, 3 low-DON (1.5 mg/kg DON) NC diets, and 3 high-DON (3 mg/kg DON) NC diets with 0, 0.17, or 0.50% AMMC incorporated at each DON level. No DON x AMMC interactions were observed. As DON level increased, ADG and final BW decreased (quadratic, P < 0.05), driven by decreased (quadratic, P < 0.01) ADFI and poorer (quadratic; P < 0.05) G:F. At both 1.5 and 3 mg/kg DON, reductions in ADG were most marked from d 0 to 7 (15 to 22% lower) and were least distinct from d 14 to 21 (5 to 6% lower). Incorporating AMMC at increasing levels had no effect on ADG, ADFI, G:F, or final BW. Overall, these experiments reinforce DON effects on feed intake but also indicate that the effects of DON on G: F may be more severe than previously thought. Furthermore, some pigs appear to develop tolerance to DON, as effects on ADFI and G: F lessen over time. However, the addition of AMMC did not offset the deleterious effects of DON.
Open Access
Novel analysis of global DNA methylation in the limbic system of the bovine brain
Cantrell, B. A.; McKay, S. D.; Weaber, Robert L.; Funston, R. N.; Lachance, H.; bweaber; Weaber, Robert L.
There has been limited research focusing on the genetic-environmental interactions in bovine brains. Global DNA methylation has been measured in brains of several species, but has yet to be examined in bovine. The objective of this study was to characterize global DNA methylation in 9 regions of the limbic system in the bovine brain: amygdala, bed nucleus of the stria terminalis, cingulate gyrus, dorsal raphe, hippocampus, hypothalamus, nucleus accumbens, periaqueductal gray, and prefrontal cortex. DNA was extracted from brain and blood samples of 6 Red Angus × Simmental steers (less than 20 mo of age), using the DNA Extraction Kit from Agilent Technologies (Santa Clara, CA) and a phenol chloroform extraction. Percent of global DNA methylation was determined using the MethylFlash Methylated DNA Quantification Kit (Colormetric) from Epigentek (Farmingdale, NY). Varying amounts of global DNA methylation were observed among the 9 functionally distinct regions of the bovine limbic system. Amygdala, bed nucleus of the stria terminalis, cingulate gyrus, dorsal raphe, periaqueductal gray, prefrontal cortex, and nucleus accumbens are all significantly different (P < 0.05) from 1 or more brain tissue type, using a paired t test in SPSS (IBM, Armonk, NY). Conversely, global DNA methylation of blood was not significantly different (P < 0.05) from any brain tissue type. This study shows significant differences in global DNA methylation among different tissue types in the limbic system of the bovine brain. Understanding the differences in global DNA methylation within different tissues in the brain will facilitate future research involving the effects of differential methylation with regard to economically important traits.
Open Access
Feeding microalgae meal (All-G Rich (TM); Schizochytrium limacinum CCAP 4067/2) to beef heifers. II: Effects on ground beef color and palatability
Phelps, Kelsey J.; Drouillard, James S.; O'Quinn, Travis; Burnett, D. D.; Blackmon, Terri L.; Axman, J. E.; Van Bibber-Krueger, Cadra L.; Gonzalez, John M.; johngonz; travisoquinn; jdrouill; Gonzalez, John M.; O'Quinn, Travis; Drouillard, James S.
The objective of this study was to examine the effects of feeding microalgae meal (All-G Rich, Schizochytrium limacinum CCAP 4087/2; Alltech Inc., Nicholasville, KY) to finishing heifers on 85% lean and 15% fat (85/15) ground beef PUFA content, palatability, and color stability. Crossbred heifers (n = 288; 452 +/- 23 kg initial BW) were allocated to pens (36 pens and 8 heifers/pen), stratified by initial pen BW (3,612 +/- 177 kg), and randomly assigned within strata to 1 of 4 treatments: 0, 50, 100, and 150 g center dot heifer(-1) center dot d(-1) of microalgae meal. After 89 d of feeding, a subset of heifers (3/pen) was harvested and the rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius were collected for processing into ground beef. At 42 d postmortem, 85/15 ground beef was formulated and formed into 112-g patties and fatty acid composition, subjective palatability, and 96-h retail color stability analyses were conducted. Increasing dietary microalgae meal concentration increased ground beef 20: 5n-3 and 22: 6n-3 fatty acids (quadratic, P < 0.01). There was a treatment x hour interaction for all color attributes (P < 0.01). On d0, microalgae tended (P = 0.08) to decrease L*, but patties had similar L* values the remainder of display (P > 0.12). Feeding microalgae meal affected (P = 0.02) b* at 24 h and decreased (linear, P = 0.08) b* at 48 h. From h 0 to 36 of display, microalgae affected redness of patties (P < 0.02), and from 48 to 72 h, microalgae meal decreased a* value (linear, P < 0.04). Microalgae meal did not impact sensory panel firmness, overall tenderness, or juiciness scores (P > 0.20) but tended to affect (P = 0.10) cohesiveness scores. As the amount of microalgae meal fed to heifers increased, beef flavor intensity decreased (linear, P < 0.01) and off-flavor intensity increased (quadratic, P < 0.05). Surface oxymyoglobin and metmyoglobin were impacted by microalgae meal from 12 to 36 h of display (P < 0.01). From 48 to 84 h of display, feeding microalgae meal to heifers decreased (linear, P < 0.09) surface oxymyoglobin and increased (linear, P < 0.02) surface metmyoglobin of patties. Although feeding microalgae meal to heifers increases the PUFA content of 85/15 ground beef, there are undesirable effects on flavor and color stability.
Open Access
Feeding microalgae meal (All-G Rich (TM); Schizochytrium limacinum CCAP 4087/2) to beef heifers. I: Effects on longissimus lumborum steak color and palatibility
Phelps, Kelsey J.; Drouillard, James S.; O'Quinn, Travis; Burnett, D. D.; Blackmon, Terri L.; Axman, J. E.; Van Bibber-Krueger, Cadra L.; Gonzalez, John M.; johngonz; travisoquinn; jdrouill; Gonzalez, John M.; O'Quinn, Travis; Drouillard, James S.
The objective of this study was to examine effects of 4 levels of microalgae meal (All-G Rich, Schizochytrium limacinum CCAP 4087/2; Alltech Inc., Nicholasville, KY) supplementation to the diet of finishing heifers on longissimus lumborum (LL) steak PUFA content, beef palatability, and color stability. Crossbred heifers (n = 288; 452 +/- 23 kg initial BW) were allocated to pens (36 pens and 8 heifers/ pen), stratified by initial pen BW (3,612 +/- 177 kg), and randomly assigned within strata to 1 of 4 treatments: 0, 50, 100, and 150 g . heifer(-1) . d(-1) of microalgae meal. After 89 d of feeding, cattle were harvested and LL were collected for determination of fatty acid composition and Warner-Bratzler shear force (WBSF), trained sensory panel evaluation, and 7-d retail color stability and lipid oxidation analyses. Feeding microalgae meal to heifers increased (quadratic, P < 0.01) the content of 22: 6n-3 and increased (linear, P < 0.01) the content of 20: 5n-3. Feeding increasing levels of microalgae meal did not impact total SFA or MUFA (P > 0.25) but tended (P = 0.10) to increase total PUFA in a quadratic manner (P = 0.03). Total omega-6 PUFA decreased (linear, P = 0.01) and total omega-3 PUFA increased (quadratic, P < 0.01) as microalgae meal level increased in the diet, which caused a decrease (quadratic, P < 0.01) in the omega-6: omega-3 fatty acid ratio. Feeding microalgae meal did not affect WBSF values or sensory panel evaluation of tenderness, juiciness, or beef flavor scores (P > 0.16); however, off-flavor intensity increased with increasing concentration of microalgae meal in the diet (quadratic, P < 0.01). From d 5 through 7 of retail display, steaks from heifers fed microalgae meal had a reduced a* value and oxymyoglobin surface percentage, with simultaneous increased surface metmyoglobin formation (quadratic, P < 0.01). Lipid oxidation analysis indicated that at d 0 and 7 of display, as the concentration of microalgae meal increased in the diet, the level of oxidation increased (quadratic, P < 0.01). Muscle fiber type percentage or size was not influenced by the inclusion of microalgae meal in diets (P > 0.19); therefore, the negative effects of microalgae on color stability were not due to fiber metabolism differences. Feeding microalgae meal to finishing heifers improves PUFA content of beef within the LL, but there are adverse effects on flavor and color stability.
Open Access
The effect of branding on consumer palatability ratings of beef strip loin steaks
Wilfong, Alaena K.; McKillip, Kassandra V.; Gonzalez, John M.; Houser, Terry A.; Unruh, John A.; Boyle, Elizabeth A.E.; O'Quinn, Travis G.; johngonz; houser; junruh; lboyle; travisoquinn; Gonzalez, John M.; Houser, Terry A.; Unruh, John A.; Boyle, Elizabeth A.E.; O'Quinn, Travis G.
The objective of this study was to determine the influence of knowing the brand or USDA grade on consumer palatability ratings of beef strip loin steaks. Strip loins were selected to represent 5 USDA grades and brands, USDA Select, Choice, Prime, Certified Angus Beef (CAB; upper 2/3 Choice), and Select, from carcasses of cattle classified as Angus on the basis of phenotype. After 21 d of aging, 2.5-cmthick steaks were cut, consecutively cut steaks were paired for consumer evaluation. Consumer panelists (n = 112) evaluated samples for tenderness, juiciness, flavor liking, and overall liking. Additionally, consumers rated each palatability trait as either acceptable or unacceptable. Samples were fed in 2 rounds on the same day: blind and informed testing. In the first round, blind testing, consumers were served 1 sample from each treatment, with no product information provided. In the second round, consumers were informed of the brand or quality grade prior to sampling. During blind testing, CAB rated similar (P > 0.05) to Choice for all palatability traits; however, CAB rated greater P < 0.05) than Choice for all traits during informed testing. Additionally, Angus Select and Select were rated similar (P > 0.05) for all traits when tested blind, but Angus Select was rated greater (P < 0.05) than Select for flavor and overall liking when brand was declared. When comparing blind and informed ratings, Angus Select and CAB had greater (P < 0.05) ratings for juiciness, flavor liking, and overall liking, and Prime had increased (P < 0.05) ratings for flavor liking and overall liking because of brand disclosure. However, ratings for Choice and Select samples were unaffected (P > 0.05) when brand was disclosed. Brand knowledge increased (P < 0.05) the percentage of Prime samples rated as acceptable for flavor and the percentage of Angus Select samples rated as acceptable for flavor and overall liking. Conversely, there was no difference (P > 0.05) in the percentage of Choice and Select samples rated as acceptable for all palatability traits. These data indicate that Prime, CAB, and Angus Select steaks receive an increase in consumer palatability perception, or "brand lift," which does not occur for Choice and Select beef.
Open Access
Effects of potential detoxifying agents on growth performance and deoxynivalenol (DON) urinary balance characteristics of nursery pigs fed DON-contaminated wheat
Frobose, Hyatt L.; Stephenson, E. W.; Tokach, Michael D.; DeRouchey, Joel M.; Woodworth, Jason C.; Dritz, Steven S.; Goodband, Robert D.; goodband; dritz; mtokach; jderouch; jwoodworth; Goodband, Robert D.; Dritz, Steven S.; Tokach, Michael D.; DeRouchey, Joel M.; Woodworth, Jason C.
Two experiments were conducted to evaluate potential detoxifying agents on growth of nursery pigs fed deoxynivalenol (DON)-contaminated diets. Naturally DON-contaminated wheat (6 mg/kg) was used to achieve desired DON levels. In a 21-d study, 238 pigs (13.4 +/- 1.8 kg BW) were used in a completely randomized design with a 2 x 2 + 1 factorial arrangement. Diets were: 1) Positive control (PC; < 0.5 mg/kg DON), 2) PC + 1.0% Product V (Nutriquest LLC, Mason City, IA), 3) Negative control (NC; 4.0 mg/kg DON), 4) NC + 1.0% Product V, and 5) NC + 1.0% sodium metabisulfite (SMB; Samirian Chemicals, Campbell, CA). There were 6 or 7 replicate pens/treatment and 7 pigs/pen. Analyzed DON was decreased by 92% when pelleted with SMB, but otherwise matched formulated levels. Overall, a DON x Product V interaction was observed for ADG (P < 0.05) with a tendency for an interaction for ADFI (P < 0.10). As anticipated, DON reduced (P < 0.001) ADG and ADFI, but the interaction was driven by even poorer growth when Product V was added to NC diets. Pigs fed NC diets had 10% poorer G: F (P < 0.001) than PC-fed pigs. Reductions in ADG due to DON were most distinct (50%) during the initial period. Adding SMB to NC diets improved (P < 0.01) ADG, ADFI, and G: F, and improved (P < 0.02) ADG and G: F compared to the PC diet. A urinary balance study was conducted using diets 3 to 5 from Exp. 1 to evaluate Product V and SMB on DON urinary metabolism. A 10 d adaptation was followed by a 7 d collection using 24 barrows in a randomized complete block design. Pigs fed NC + SMB diet had greater urinary DON output (P < 0.05) than pigs fed NC + Product V, with NC pigs intermediate. Daily DON excretion was lowest (P < 0.05) in the NC + SMB pigs. However, degradation of DON-sulfonate back to the parent DON molecule was observed as pigs fed NC + SMB excreted more DON than they consumed (164% of daily DON intake), greater (P < 0.001) than pigs fed the NC (59%) or NC + Product V (48%). Overall, Product V did not alleviate DON effects on growth nor did it reduce DON absorption and excretion. However, hydrothermally processing DON-contaminated diets with 1.0% SMB restored ADFI and improved G: F. Even so, the urinary balance experiment revealed that some of the converted DON-sulfonate can degrade back to DON under physiological conditions. While further research is needed to discern the stability of the DON-sulfonate, SMB appears promising to restore performance in pelleted DON-contaminated diets.
Open Access
Genotype by environment interactions for growth in Red Angus
Fennewald, D. J.; Weaber, Robert L.; Lamberson, W. R.; bweaber; Weaber, Robert L.
Accuracy of sire selection is limited by how well animals are characterized for their environment. The objective of this study was to evaluate the presence of genotype x environment interactions (GxE) for birth weight (BiW) and weaning weight (WW) for Red Angus in the United States. Adjusted weights were provided by the Red Angus Association of America. Environments were defined as 9 regions within the continental United States with similar temperature-humidity indices. Mean weights of calves were determined for each region and for each sire's progeny within each region. A reaction norm (RN) for each bull was estimated by regressing the sire means on the region means weighted for the number of progeny of each sire. The range for BiW and WW RN was -1.3 to 4.0 and -1.7 to 2.8, respectively. The heritabilities of BiW and WW RN were 0.40 and 0.39, respectively. Phenotypic and genetic correlations between BiW and WW RN were 0.19 and 0.54, respectively. The phenotypic correlation of the progeny mean to the RN was -0.20 (P < 0.05) and suggests that sires with higher means are more stable in progeny performance across environments. Weights in different regions were considered separate traits and genetic correlations were estimated between all pairs of regions as another method to determine GxE. Genetic correlations < 0.80 indicate GxE at a level for concern, but existed for only 2 of 36 estimates for BiW and 12 of 36 estimates for WW. Genetic correlations between different regions ranged from 0.74 to 0.96 for BiW and 0.62 to 0.99 for WW and indicate that sires tend to rank similarly across environments for these traits.
Open Access
Effect of pelleting on survival of porcine epidemic diarrhea virus-contaminated feed
Cochrane, R. A.; Schumacher, L. L.; Dritz, Steven S.; Woodworth, Jason C.; Huss, Anne R.; Stark, Charles R.; DeRouchey, J. M.; Tokach, Michael D.; Goodband, Robert D.; Bai, Jianfa; Chen, Q.; Zhang, J.; Gauger, P. C.; Derscheid, R. J.; Magstadt, D. R.; Main, R. G.; Jones, Cassandra K.; jonesc; dritz; jwoodworth; crstark; mtokach; goodband; jbai; Jones, Cassandra K.; Dritz, Steven S.; Woodworth, Jason C.; Stark, Charles R.; Tokach, Michael D.; Goodband, Robert D.; Bai, Jianfa
Porcine epidemic diarrhea virus (PEDV) is a heat-sensitive virus that has devastated the U.S. swine industry. Because of its heat sensitivity, we hypothesized that a steam conditioner and pellet mill mimicking traditional commercial thermal processing may mitigate PEDV infectivity. Pelleting, a common feed processing method, includes the use of steam and shear forces, resulting in increased temperature of the processed feed. Two thermal processing experiments were designed to determine if different pellet mill conditioner retention times and temperatures would impact PEDV quantity and infectivity by analysis of quantitative reverse transcription PCR and bioassay. In Exp. 1, a 3 x 3 x 2 factorial design was used with 3 pelleting temperatures (68.3, 79.4, and 90.6 degrees C), 3 conditioning times (45, 90, or 180 s), and 2 doses of viral inoculation (low, 1 x 102 tissue culture infectious dose(50) (the concentration used to see cytopathic effect in 50% of the cells)/g, or high, 1 x 10(4) tissue culture infectious dose(50)/g). Noninoculated and PEDV-inoculated unprocessed mash were used as controls. The low-dose PEDV-infected mash had 6.8 +/- 1.8 cycle threshold (Ct) greater (P < 0.05) PEDV than the high-dose mash. Regardless of time or temperature, pelleting reduced (P < 0.05) the quantity of detectable viral PEDV RNA compared with the PEDV-inoculated unprocessed mash. Fecal swabs from pigs inoculated with the PEDV-positive unprocessed mash, regardless of dose, were clinically PEDV positive from 2 to 7 d (end of the trial) after inoculation. However, if either PEDV dose of inoculated feed was pelleted at any of the 9 tested conditioning time x temperature combinations, no PEDV RNA was detected in fecal swabs or cecum content. Based on Exp. 1 results, a second experiment was developed to determine the impact of lower processing temperatures on PEDV quantity and infectivity. In Exp. 2, PEDV-inoculated feed was pelleted at 1 of 5 conditioning temperatures (37.8, 46.1, 54.4, 62.8, and 71.1 degrees C) for 30 s. The 5 increasing processing temperatures led to feed with respective mean Ct values of 32.5, 34.6, 37.0, 36.5, and 36.7, respectively. All samples had detectable PEDV RNA. However, infectivity was detected by bioassay only in pigs from the 37.8 and 46.1 degrees C conditioning temperatures. Experiment 2 results suggest conditioning and pelleting temperatures above 54.4 degrees C could be effective in reducing the quantity and infectivity of PEDV in swine feed. However, additional research is needed to prevent subsequent recontamination after pelleting as it is a point-in-time mitigation step.
Open Access
Determination of the effect of brand and product identification on consumer palatability ratings of ground beef patties
Wilfong, Alaena K.; McKillip, Kassandra V.; Gonzalez, John M.; Houser, Terry A.; Unruh, John A.; Boyle, Elizabeth A.E.; O'Quinn, Travis G.; johngonz; houser; junruh; lboyle; travisoquinn; Gonzalez, John M.; Houser, Terry A.; Unruh, John A.; Boyle, Elizabeth A.E.; O'Quinn, Travis G.
The objective of this study was to determine the effect of brand and product identification on consumer palatability ratings of ground beef patties. Six treatments were used in the study: 90/10 Certified Angus Beef (CAB) ground sirloin, 90/10 ground beef, 80/20 CAB ground chuck, 80/20 ground chuck, 80/20 ground beef, and 73/27 CAB ground beef. Ground beef was processed into 151.2-g patties using a patty former with 2 consecutively formed patties assigned to blind consumer testing and the following 2 assigned to informed testing. Following cooking to 74 degrees C, patties were cut into quarters and served to consumers. Consumers (n = 112) evaluated samples in 2 rounds for tenderness, juiciness, flavor liking, texture liking, and overall liking. Each trait was also rated as either acceptable or unacceptable. In the first round of testing, samples were blind evaluated, with no information about the treatments provided to consumers, but in the second round, product type and brand were disclosed prior to sample evaluation. Additionally, texture profile and shear force analyses were performed on patties from each treatment. Few differences were observed for palatability traits during blind consumer testing; however, during informed testing, 90/10 CAB ground sirloin was rated greatest (P < 0.05) for all palatability traits other than juiciness. Also, 90/10 CAB ground sirloin had increased (P < 0.05; (consumer informed score -consumer blind score)/consumer blind score) ratings for tenderness (17.4%), juiciness (36.5%), flavor liking (23.3%), texture liking (18.2%), and overall liking (24.7%) due to brand disclosure. Increased (P < 0.05) ratings were found for CAB products for multiple traits due to treatment disclosure, whereas the only non-CAB-branded product that received increased (P < 0.05) ratings during informed testing was 90/10 ground beef for tenderness and juiciness. Texture results indicated that decreased fat level increased hardness, cohesiveness, gumminess, and chewiness. These results indicate that when sampling ground beef without brand and product information, few consumers find differences in eating quality among ground beef treatments; however, when consumers are aware of the brand, fat level, and subprimal blend prior to sampling, these factors have a large impact on consumer eating satisfaction.
Open Access
Effects of distillers dried grains with solubles and added fat fed immediately before slaughter on growth performance and carcass characteristics of finishing pigs
Coble, K. F.; DeRouchey, Joel M.; Tokach, Michael D.; Dritz, Steven S.; Goodband, Robert D.; Woodworth, Jason C.; goodband; jderouch; mtokach; dritz; jwoodworth; Goodband, Robert D.; DeRouchey, Joel M.; Tokach, Michael D.; Dritz, Steven S.; Woodworth, Jason C.
The addition of dietary fat has been shown to increase HCW and carcass yield in pigs fed low-fiber corn-soy diets; however, data on added fat in high-fiber, low-energy diets is less available. Therefore, the potential for dietary fat to ameliorate the negative effect high-fiber diets have on carcass yield during the last 3 wk before slaughter is of high importance. This experiment was conducted to determine the interactive effects of 30% distillers dried grains with solubles (DDGS) and 5% added fat fed before slaughter on growth performance and carcass characteristics. A total of 1,258 pigs in 2 groups (initially 105.8 +/- 0.1 kg BW; group 1 PIC 337 x 1,050; group 2 PIC 327 x 1,050) were used in a 20-d experiment. All pigs were fed a common diet with 30% DDGS until 20 d before slaughter. Then, all pens were weighed and allotted to treatments with 20 replicate pens per treatment. Dietary treatments were arranged in a 2 x 2 factorial with 2 diet types (corn-soybean meal-based with or without 30% DDGS) and added fat (0 or 5%; group 1 = tallow; group 2 = choice white grease). Diets were formulated to a constant standardized ileal digestible Lys: NE ratio. There were no treatment x group interactions for any response criteria. Thus, data for the 2 groups were combined for analysis. Overall, there was a tendency for a diet type x added fat interaction for ADG (P = 0.054), whereas this was significant for G: F (P = 0.008). This was a result of 5% added fat increasing ADG and G: F to a greater magnitude for pigs fed the diet containing 30% DDGS (8.6 and 10.4%, respectively) than for pigs fed the corn-soy diet (2.0 and 2.9%, respectively). Although diet type did not affect final live BW, pigs fed the diet containing DDGS had decreased HCW and carcass yield (P < 0.05). Adding 5% fat did not affect carcass yield. In conclusion, adding 5% fat to finishing pig diets containing 30% DDGS approximately 20 d before slaughter improved ADG and G: F but did not overcome the reduction in carcass yield from feeding DDGS.
Open Access
Evaluating pellet and meal feeding regimens on finishing pig performance, stomach morphology, and carcass characteristics
De Jong, Jon A.; DeRouchey, Joel M.; Tokach, Michael D.; Dritz, Steven S.; Goodband, Robert D.; Woodworth, Jason C.; Allerson, M. W.; jderouch; mtokach; dritz; goodband; jwoodworth; DeRouchey, Joel M.; Tokach, Michael D.; Dritz, Steven S.; Goodband, Robert D.; Woodworth, Jason C.
A total of 2,100 pigs (PIC 327 x 1050; initially 31.2 kg BW) were used in a 118-d trial to determine the effects of pellet or meal feeding regimens on finishing pig growth performance, stomach morphology, and carcass characteristics. Pens of pigs were balanced by initial BW and randomly allotted to 1 of 6 dietary treatments (14 pens/treatment with 25 pigs/pen). Pens were sorted by gender allowing for 7 barrow pens and 7 gilt pens per treatment. The same corn-soybean meal-based diets containing 15% dried distillers' grains with solubles were used for all treatments and fed in 5 phases. Phases were fed from d 0 to 28, 28 to 56, 56 to 84, 84 to 98, and 98 to 118. The 6 treatments included a meal or pelleted diet fed from d 0 to 118, a meal diet fed from d 0 to 70 followed by pellets from d 70 to 118, a pelleted diet fed from d 0 to 70 followed by a meal diet from d 70 to 118, or pellets and meal rotated every 2 wk starting with meal or pellets. On d 110, 4 pigs from each pen were harvested and stomachs collected, from which a combined ulcer and keratinization score was determined for each pig. Overall, there were no differences in ADG across feeding regimens. Pigs fed meal throughout had the greatest (P < 0.05) ADFI, whereas pigs fed pellets throughout had the lowest (P < 0.05), with all other treatments intermediate (P < 0.05). Pigs fed pelleted diets throughout had the greatest (P < 0.05) G: F, whereas pigs fed meal throughout had the worst G: F (P < 0.05), with all other treatments intermediate (P < 0.05). When pelleted diets were fed for the last 58 d or for the entire trial, the incidence of ulceration and keratinization increased (P < 0.05), whereas pigs fed meal for the last 58 d had a lower incidence (P < 0.05), with all other treatments intermediate (P < 0.05). Feeding pellets throughout increased (P < 0.05) the number of pigs removed per pen compared with all other treatments. Pig removals were determined by an on-site farm manager when pigs were at risk due to weight loss, health, or animal welfare concerns and needed to be separated from the general population. There were no differences for any carcass characteristics measured including HCW, carcass yield, backfat depth, loin depth, and percentage lean. In conclusion, feeding pelleted diets improved G: F but increased stomach ulceration and pig removals; however, rotating pellets and meal diets provided an intermediate G: F response and moderated stomach ulcerations compared with feeding only pellets.
Open Access
Effect of shade on animal welfare, growth performance, and carcass characteristics in large pens of beef cattle fed a beta agonist in a commercial feedlot
Hagenmaier, Jacob A.; Reinhardt, Christopher D.; Bartle, Steven J.; Thomson, Daniel U.; cdr3; sjbartle; thomson; Reinhardt, Christopher D.; Bartle, Steven J.; Thomson, Daniel U.
Feedlot cattle (n = 1,395; BW = 568 +/- 43 kg) were used to evaluate the effects of shade on animal welfare, growth performance, and carcass quality during the summer of 2013 in a Kansas commercial feedlot. Seven lots of predominately black steers and heifers (4 and 3, respectively) visually determined to be approaching the final mo on feed were identified, randomly gate-sorted, and allocated to pens located across the feed alley from each other to receive 1 of 2 treatments: 1) Shade (mean shade area = 1.5 m(2)/animal) or 2) No shade. Shade was provided using a 13-ounce polyethylene fabric and pens were oriented northwest to southeast. The mean starting date was June 13 and the mean days on feed for lots while on the study was 38 d. Cattle were fed a 77.67% DM steam-flaked corn-based diet and had ad libitum access to water throughout the duration of the trial. Zilpaterol hydrochloride (ZIL) was included in the finishing ration at an inclusion rate of 8.3 mg/kg of DM for the last 20 d on feed with a 3 d withdrawal period. Pen floor temperatures (PFT) were measured using an infrared thermometer and prevalence of cattle open-mouth breathing (OMB) was recorded on a pen basis. In addition to shade treatment, the effect of temperature humidity index (THI) on PFT and OMB was analyzed by classifying days as either "Alert" (THI < 79) or "Danger" (THI > 79). On the day of slaughter, pens within a replicate were kept separate through all stages of the marketing channel from loading at the feedlot until stunning at the plant. Pen served as the experimental unit for all measurements. There was a THI x shade treatment interaction for PFT and OMB (P < 0.001) where days classified as "Danger" increased PFT and prevalence of OMB compared to "Alert" days in unshaded but not shaded cattle. Shaded cattle had greater DMI (P = 0.01); however, unshaded cattle had greater G:F (P = 0.05) and therefore no differences were observed in ADG (P = 0.39). Shaded cattle had greater dressing percentage (P = 0.01), although HCW, LM area, fat thickness, marbling score, and quality grade did not differ between treatments (P > 0.05). Heat stress, a significant animal welfare concern and cause of reduced performance in feedlot cattle during the final phase of the feeding period, was alleviated in shaded cattle and illustrates the importance of shade provision as 1 tool to protect the welfare and increase feed consumption in large pens of feedlot cattle during hot summer months.
Open Access
Using estrus detection patches to optimally time insemination improved pregnancy risk in suckled beef cows enrolled in a fixed-time artificial insemination program
Hill, Scott L.; Grieger, David M.; Olson, K.C.; Jaeger, John R.; Dahlen, C. R.; Bridges, G. A.; Dantas, F.; Larson, J. E.; Muth-Spurlock, A. M.; Ahola, J. K.; Fischer, M. C.; Perry, G. A.; Larimore, E. L.; Steckler, T. L.; Whittier, W. D.; Currin, J. F.; Stevenson, Jeffrey S.; jss; jrjaeger; kcolson; dgrieger; Stevenson, Jeffrey S.; Jaeger, John R.; Olson, KC; Grieger, David M.
A multilocation study examined pregnancy risk (PR) after delaying AI in suckled beef cows from 60 to 75 h when estrus had not been detected by 60 h in response to a 7-d CO-Synch + progesterone insert (CIDR) timed AI (TAI) program (d-7: CIDR insert concurrent with an injection of GnRH; d 0: PGF(2 alpha) injection and removal of CIDR insert; and GnRH injection at TAI [ 60 or 75 h after CIDR removal]). A total of 1,611 suckled beef cows at 15 locations in 9 states (CO, IL, KS, MN, MS, MT, ND, SD, and VA) were enrolled. Before applying the fixed-time AI program, BCS was assessed, and blood samples were collected. Estrus was defined to have occurred when an estrus detection patch was >50% colored (activated). Pregnancy was determined 35 d after AI via transrectal ultrasound. Cows (n = 746) detected in estrus by 60 h (46.3%) after CIDR removal were inseminated and treated with GnRH at AI (Control). Remaining nonestrous cows were allocated within location to 3 treatments on the basis of parity and days postpartum: 1) GnRH injection and AI at 60 h (early-early = EE; n = 292), 2) GnRH injection at 60 h and AI at 75 h (early-delayed = ED; n = 282), or 3) GnRH injection and AI at 75 h (delayed-delayed = DD; n = 291). Control cows had a greater (P < 0.01) PR (64.2%) than other treatments (EE = 41.7%, ED = 52.8%, DD = 50.0%). Use of estrus detection patches to delay AI in cows not in estrus by 60 h after CIDR insert removal (ED and DD treatments) increased (P < 0.05) PR to TAI when compared with cows in the EE treatment. More (P < 0.001) cows that showed estrus by 60 h conceived to AI at 60 h than those not showing estrus (64.2% vs. 48.1%). Approximately half (49.2%) of the cows not in estrus by 60 h had activated patches by 75 h, resulting in a greater (P < 0.05) PR than their nonestrous herd mates in the EE (46.1% vs. 34.5%), ED (64.2% vs. 39.2%), and DD (64.8% vs. 31.5%) treatments, respectively. Overall, cows showing estrus by 75 h (72.7%) had greater (P < 0.001) PR to AI (61.3% vs. 37.9%) than cows not showing estrus. Use of estrus detection patches to allow for a delayed AI in cows not in estrus by 60 h after removal of the CIDR insert improved PR to TAI by optimizing the timing of the AI in those cows.
Open Access
Evaluating the impact of maternal vitamin D supplementation on sow performance: II. Subsequent growth performance and carcass characteristics of growing pigs
Flohr, Joshua R.; Woodworth, Jason C.; Bergstrom, J. R.; Tokach, Michael D.; Dritz, Steven S.; Goodband, Robert D.; DeRouchey, Joel M.; jwoodworth; mtokach; dritz; goodband; jderouch; Woodworth, Jason C.; Tokach, Michael D.; Dritz, Steven S.; Goodband, Robert D.; DeRouchey, Joel M.
A of subsample of 448 growing pigs (PIC 327 x 1050) weaned from 52 sows fed varying dietary vitamin D regimens were used in a split-plot design to determine the effects of maternal and nursery dietary vitamin D on growth performance. Sows were previously administered diets containing vitamin D as vitamin D-3 (800, 2,000, or 9,600 IU/kg) or as 25(OH) D3 (50 mu g [or 2,000 IU vitamin D equivalent]/kg from HyD; DSM Nutritional Products, Parsippany, NJ). Once weaned, pigs were allotted to pens on the basis of previous maternal vitamin D treatment, and then pens were randomly assigned to 1 of 2 nursery vitamin D dietary regimens (2,000 IU of vitamin D-3/ kg or 50 mu g 25(OH) D-3/kg). Pigs remained on nursery vitamin D treatments for 35 d, and then they were provided common finishing diets until market (135 kg). Growing pig serum 25(OH)D-3 suggested that maternal dietary vitamin D influenced (P < 0.001 at weaning) serum concentrations early after weaning, but nursery vitamin D regimen had a larger impact (P < 0.001) on d 17 and 35 postweaning. Overall growth performance was not influenced by nursery vitamin D dietary treatments. From d 0 to 35 in the nursery, pigs from sows fed increasing vitamin D3 had increased (quadratic, P < 0.003) ADG and ADFI, but G:F was similar regardless of maternal vitamin D regimen. Also, pigs from sows fed 50 mu g/kg of 25(OH) D-3 had increased (P = 0.002) ADG compared with pigs weaned from sows fed 800 IU of vitamin D3. Throughout finishing (d 35 postweaning until 135 kg), ADG was increased (quadratic, P = 0.005) and G: F was improved (quadratic, P = 0.049) with increasing maternal dietary vitamin D-3. Also, pigs from sows fed 50 mu g/kg of 25(OH)D-3 had increased (P = 0.002) ADG compared with pigs weaned from sows fed 800 IU of vitamin D-3. Carcass data were collected from a subsample population separate from that used for the growth performance portion of the study, and a total of 642 carcasses from progeny of sows fed the varying dietary vitamin D treatments were used. Live BW of pigs at marketing and HCW were heavier (P < 0.030) for pigs from sows previously fed 25(OH)D-3 compared with pigs from sows fed 9,600 IU of vitamin D-3. Overall, pigs from sows fed 2,000 IU of vitamin D-3 grew faster after weaning compared with pigs from sows fed 800 or 9,600 IU of vitamin D-3. Pigs from sows fed 25(OH)D-3 hag greater ADG compared with pigs from sows fed 800 IU of vitamin D-3, and they had increased final BW and HCW compared with pigs from sows fed 9,600 IU of vitamin D-3.