Feeding wet distillers grains plus solubles with and without a direct-fed microbial to determine performance, carcass characteristics, and fecal shedding of Escherichia coli O157:H7 in feedlot heifers

Citation: Wilson, B. K., Holland, B. P., Step, D. L., Jacob, M. E., VanOverbeke, D. L., Richards, C. J., . . . Krehbiel, C. R. (2016). Feeding wet distillers grains plus solubles with and without a direct-fed microbial to determine performance, carcass characteristics, and fecal shedding of Escherichia coli O157:H7 in feedlot heifers. Journal of Animal Science, 94(1), 297-305. doi:10.2527/jas2015-9601The inclusion of wet distillers grains plus solubles (WDGS) in feedlot diets has become a common practice in many regions of the United States due to the expanded production of byproducts and fluctuating corn prices related to ethanol production and other factors. In addition, societal concerns over the continued use of antimicrobials in agriculture production combined with an enhanced interest in disease and pathogen prevention in the food supply have led to an increased interest in use of direct-fed microbials (DFM) in growing and finishing cattle. Direct-fed microbials have been shown to improve ADG and feed efficiency, alter ruminal fermentation, and decrease fecal shedding of potential harmful pathogens in feedlot cattle in some experiments. The objective of this experiment was to evaluate the effects of WDGS inclusion with or without a DFM containing Lactobacillus acidophilus (1 x 10(6) cfu . heifer(-1) . d(-1)) combined with Propionibacterium freudenreichii (1 x 10(9) cfu , heifer(-1) . d(-1)) on the performance, carcass characteristics, and Escherichia coli O157:H7 shedding in feedlot heifers. In early August, 288 crossbred heifers (initial BW = 295 +/- 28 kg) were assigned to 1 of 4 treatments (12 pens per treatment; 6 heifers per pen) in a randomized complete block design with a 2 x 2 factorial arrangement of treatments. Body weights and fecal grab samples were obtained at approximately 28-d intervals throughout the experiment. Across the feeding period, heifers fed 30% WDGS tended (P = 0.09) to have greater ADG and had greater carcass-adjusted ADG (P = 0.05) compared with heifers fed dry-rolled corn (DRC). Dry matter intake was not affected (P = 0.65) by diet, although carcass-adjusted G:F tended (P = 0.10) to be improved for heifers fed WDGS. Heifers fed 30% WDGS tended (P 0.10) on performance or carcass merit in the present experiment. The incidence of E. coli O157:H7 throughout the experiment was low, with only 18 positive samples across all sampling periods. Neither WDGS inclusion nor the inclusion of L. acidophilus combined with P. freudenreichii in the diet had any effect (P > 0.10) on E. coli O157:H7 shedding in this experiment. Feeding 30% WDGS to feedlot heifers improved animal performance compared to the DRC-based control diet

Genome-wide association study of concentrations of iron and other minerals in longissimus muscle of Angus cattle1

The objective of this study was to characterize variation and identify SNP and chromosomal regions associated with mineral concentrations in LM of Angus beef cattle. Samples of LM from 2,285 Angus cattle were obtained and concentrations of seven minerals including iron, magnesium, manganese, phosphorus, potassium, sodium, and zinc were quantified. Genomic DNA extracted from the ground beef sample used for mineral composition was genotyped with the Bovine SNP50 Infinium II BeadChip and effects of SNP on each trait were estimated using the Bayes-Cπ module of GenSel software. Pedigree-based estimates of heritabilities and corresponding genetic variances indicate iron was the only mineral concentration, which could be considered a good candidate for manipulation by genomic selection. The amount of variation that could be accounted for by SNP genotypes was concordant with pedigree-based heritabilities and varied from very low for potassium and sodium (< 0.09) to medium-high (0.37) for iron. Though significant chromosomal regions were identified for all minerals analyzed in this study, further study focused on iron. Seven regions on six chromosomes (1, 2, 7, 10, 15 and 28) were identified to have major effect on iron content of LM in Angus cattle. The accuracy of direct genomic values (DGV) for iron concentration was estimated using a five-fold cross-validation strategy. The accuracy of DGV estimated as the genetic correlation between DGV and the phenotype (iron concentration) adjusted for contemporary groups was 0.59. A bivariate animal model was used to estimate genetic correlations between iron concentrations and a reduced set of economically important carcass traits: HCW, ribeye area, calculated USDA yield grade, percent KPH, and marbling score. The genetic correlations between iron concentration and HCW, percentage KPH, marbling score and ribeye area were small (-0.19 - 0.15) and non-significant. Although still weak (0.22), a positive significant genetic correlation was identified between iron content and USDA calculated yield grade. Beef is a major contributor of iron and zinc in the human diet, and this study found that iron content might be effectively manipulated through marker-assisted selection programs, without compromising other carcass and palatability traits

Genetic parameters for concentrations of minerals in longissimus muscle and their associations with palatability traits in Angus cattle

The objective of this study was to estimate genetic parameters for concentrations of minerals in LM and to evaluate their associations with beef palatability traits. Samples of LM from 2,285 Angus cattle were obtained and fabricated into steaks for analysis of mineral concentrations and for trained sensory panel assessments. Nine minerals, including calcium, copper, iron, magnesium, manganese, phosphorus, potassium, sodium, and zinc, were quantified. Restricted maximum likelihood procedures were used to obtain estimates of variance and covariance components under a multiple-trait animal model. Estimates of heritability for mineral concentrations in LM varied from 0.01 to 0.54. Iron and sodium were highly and moderately heritable, respectively, whereas the other minerals were lowly heritable except for calcium, copper, and manganese, which exhibited no genetic variation. Strong positive genetic correlations existed between iron and zinc (0.49, P \u3c 0.05), between magnesium and phosphorus (0.88, P \u3c 0.05), between magnesium and sodium (0.68, P \u3c 0.05), and between phosphorus and potassium (0.69, P \u3c 0.05). Overall tenderness assessed by trained sensory panelists was positively associated with manganese, potassium, and sodium and negatively associated with phosphorus and zinc concentrations (P \u3c0.05). Juiciness assessed by trained sensory panelists was negatively associated with magnesium and positively associated with manganese and sodium concentrations (P \u3c 0.05). Livery or metallic flavor was not associated with any of the minerals (P \u3e 0.05). Beefy flavor was positively associated with calcium, iron, and zinc and negatively associated with sodium concentration, whereas a painty or fishy flavor was positively associated with sodium and negatively associated with calcium and potassium concentrations (P \u3c 0.05). Beef is a major contributor of iron and zinc in the human diet, and these results demonstrate sufficient genetic variation for these traits to be improved through marker-assisted selection programs without compromising beef palatability

Genetic parameters for carnitine, creatine, creatinine, carnosine, and anserine concentration in longissimus muscle and their association with palatability traits in Angus cattle

The objective of this study was to estimate genetic parameters for carnitine, creatine, creatinine, carnosine, and anserine concentration in LM and to evaluate their associations with Warner-Bratzler shear force (WBSF) and beef palatability traits. Longissimus muscle samples from 2,285 Angus cattle were obtained and fabricated into steaks for analysis of carnitine, creatine, creatinine, carnosine, anserine, and other nutrients, and for trained sensory panel and WBSF assessments. Restricted maximum likelihood procedures were used to obtain estimates of variance and covariance components under a multiple-trait animal model. Estimates of heritability for carnitine, creatine, creatinine, carnosine, and anserine concentrations in LM from Angus cattle were 0.015, 0.434, 0.070, 0.383, and 0.531, respectively. Creatine, carnosine, and anserine were found to be moderately heritable, whereas almost no genetic variation was observed in carnitine and creatinine. Moderate positive genetic (0.25, P \u3c 0.05) and phenotypic correlations (0.25, P \u3c 0.05) were identified between carnosine and anserine. Medium negative genetic correlations were identified between creatine and both carnosine (-0.53, P\u3c 0.05) and anserine (-0.46, P \u3c 0.05). Beef and livery/metallic flavor were not associated with any of the 5 compounds analyzed (P \u3e 0.10), and carnitine concentrations were not associated (P \u3e 0.10) with any of the meat palatability traits analyzed. Carnosine was negatively associated with overall tenderness as assessed by trained sensory panelists. Similar negative associations with overall tenderness were identified for creatinine and anserine. Painty/fishy was the only flavor significantly and negatively associated with creatinine and carnosine. These results provide information regarding the concentration of these compounds, the amount of genetic variation, and evidence for negligible associations with beef palatability traits in LM of beef cattle

Effects of feeding zilpaterol hydrochloride for twenty to forty days on carcass cutability and subprimal yield of calf-fed Holstein steers

El presente trabajo de investigación se realizó con el propósito de Determinar la relación de los estilos de aprendizaje en el rendimiento académico- área de Ingles- en estudiantes de cuarto grado de secundaria del C.P.M. "San Pedro Chanel", Sullana- Piura, 2017. Para el desarrollo de la investigación se utilizó un diseño Correlacional, No Experimental Transversal, así como una población de 1700 estudiantes del nivel secundaria y una muestra No probabilística de 36 estudiantes de cuarto grado de secundaria del aula ?B?. Para la recopilación de la información se utilizó como técnica a la encuesta y como instrumento un cuestionario con escala valorativa referido a la variable Estilos de aprendizaje y para la variables Rendimiento académico se utilizó como técnica al análisis documental y como instrumento una ficha de análisis documental. La información recopilada se registró y procesó utilizando el programa SPSS V19, a partir de lo cual se presentan los resultados en tablas, así como también se realizó el análisis correlacional a través del coeficiente de Pearson. Según los resultados obtenidos existe relación moderada entre las dimensiones estilo de aprendizaje activo y estilo de aprendizaje pragmático en el rendimiento académico en los estudiantes con un coeficiente de Pearson de (0.480 y 0.561); existe relación alta entre el estilo de aprendizaje reflexivo y el rendimiento académico en los estudiantes con un coeficiente de Pearson de (0.634) y existe relación baja entre el estilo de aprendizaje teórico y el rendimiento académico en los estudiantes con un coeficiente de Pearson de (0.382).Tesi

Modes, mechanisms and evidence of bet hedging in rotifer diapause traits

In this contribution, we review our knowledge on bet-hedging strategies associated with rotifer diapause. First, we describe the ecological scenario under which bet hedging is likely to have evolved in three diapause-related traits in monogonont rotifer populations: (1) the timing of sex (because diapausing eggs are produced via sexual reproduction), (2) the sexual reproduction ratio (i.e. the fraction of sexually reproducing females) and (3) the timing of diapausing egg hatching. Then, we describe how to discriminate among bet-hedging modes and discuss which modes and mechanisms better fit the variability observed in these traits in rotifers. Finally, we evaluate the strength of the empirical evidence for bet hedging in the scarce studies available, and we call for the need of research at different levels of biological complexity to fully understand bet hedging in rotifer diapause

The Effects of Zilpaterol Hydrochloride on Carcass Cutability and Tenderness of Calf-Fed Holstein Steers

To evaluate the impact of zilpaterol hydrochloride (ZH) on carcass cutability and tenderness of calf-fed Holstein steers, calf-fed Holstein carcasses (n = 102) were selected from a pool of 2,300 steers that were fed 0 or 8.3 mg/kg (DM basis) of ZH. Zilpaterol hydrochloride was supplemented the last 20 d of the finishing period and withdrawn for 3 d before slaughter. Carcasses were selected based on carcass weight as well as predetermined USDA Yield grade categories. For tenderness evaluation, steaks from the strip loin, bottom round, and top round (n = 54 per subprimal) were aged for 14 or 21 d postmortem. Carcasses from ZH-fed steers had more (P \u3c 0.01) saleable yield than carcasses from control-fed steers. Additionally, ZH-fed steers had greater (P ≤ 0.01) subprimal yield from the shoulder clod, strip loin, peeled tenderloin, top sirloin butt, bottom sirloin tri-tip, peeled knuckle, inside round, bottom round flat, eye of round, heel, and shank. Furthermore, ZH decreased (P \u3c 0.01) the total amount and percentage of bone and fat trim from the carcass. Moisture loss was not affected by ZH in LM or inside round steaks (P \u3e 0.05); however, ZH increased thawing loss (P = 0.05) but reduced cooking loss (P = 0.05) in bottom round steaks. Shear force values of LM and inside round steaks increased with ZH inclusion (P \u3c 0.01), but there was no difference in bottom round steaks (P \u3e 0.05). Steaks aged for 21 d had smaller (P \u3c 0.01) Warner-Bratzler shear force (WBS) values than 14-d steaks from all 3 subprimals. Trained sensory panelists did not detect any differences (P \u3e 0.05) in sensory juiciness, tenderness, or flavor variables of LM or inside round steaks, except ZH steaks from the LM received smaller scores for sustained juiciness (P = 0.01) and overall tenderness (P = 0.04) than control steaks. Although LM steaks from ZH cattle were tougher than control steaks, the ZH-treated steaks had an average WBS value of 4.10 kg, which would be classified as intermediate in tenderness, with trained panelists rating ZH steaks slightly to moderately tender. Feeding ZH improved carcass cutability of calf-fed Holstein steers; however, tenderness was reduced in LM and inside round steaks. The interaction of postmortem tenderization techniques should be investigated to evaluate their impact on palatability in cattle supplemented with β-agonists to allow the beef industry to take full advantage of the enhancement in performance and carcass yield

Feeding wet distillers grains plus solubles with and without a direct-fed microbial to determine performance, carcass characteristics, and fecal shedding of \u3ci\u3eEscherichia coli\u3c/i\u3e O157:H7 in feedlot heifers

The inclusion of wet distillers grains plus solubles (WDGS) in feedlot diets has become a common practice in many regions of the United States due to the expanded production of byproducts and fluctuating corn prices related to ethanol production and other factors. In addition, societal concerns over the continued use of antimicrobials in agriculture production combined with an enhanced interest in disease and pathogen prevention in the food supply have led to an increased interest in use of direct-fed microbials (DFM) in growing and finishing cattle. Direct-fed microbials have been shown to improve ADG and feed efficiency, alter ruminal fermentation, and decrease fecal shedding of potential harmful pathogens in feedlot cattle in some experiments. The objective of this experiment was to evaluate the effects of WDGS inclusion with or without a DFM containing Lactobacillus acidophilus (1 × 106 cfu ∙ heifer−1 ∙ d−1) combined with Propionibacterium freudenreichii (1 × 109 cfu ∙ heifer−1 ∙ d−1) on the performance, carcass characteristics, and Escherichia coli O157:H7 shedding in feedlot heifers. In early August, 288 crossbred heifers (initial BW = 295 ± 28 kg) were assigned to 1 of 4 treatments (12 pens per treatment; 6 heifers per pen) in a randomized complete block design with a 2 × 2 factorial arrangement of treatments. Body weights and fecal grab samples were obtained at approximately 28-d intervals throughout the experiment. Across the feeding period, heifers fed 30% WDGS tended (P = 0.09) to have greater ADG and had greater carcass-adjusted ADG (P = 0.05) compared with heifers fed dry-rolled corn (DRC). Dry matter intake was not affected (P = 0.65) by diet, although carcass-adjusted G:F tended (P = 0.10) to be improved for heifers fed WDGS. Heifers fed 30% WDGS tended (P \u3c 0.10) to have greater fat thickness at the 12th rib, lower marbling scores, and higher yield grades. The inclusion of L. acidophilus combined with P. freudenreichii in the diet had no effect (P \u3e 0.10) on performance or carcass merit in the present experiment. The incidence of E. coli O157:H7 throughout the experiment was low, with only 18 positive samples across all sampling periods. Neither WDGS inclusion nor the inclusion of L. acidophilus combined with P. freudenreichii in the diet had any effect (P \u3e 0.10) on E. coli O157:H7 shedding in this experiment. Feeding 30% WDGS to feedlot heifers improved animal performance compared to the DRC-based control diet