Histological and steroidogenic changes within dominant ovarian follicles (DFs) undergoing atresia following systemic administration of oestradiol benzoate (ODB) were characterized in beef heifers. At 5.6+/-0.1 days after the onset of oestrus, heifers received 1 mg ODB i.m./500 kg body weight (ODB; n=15) or served as controls (n=15). Timing of treatment ...

Increasing public concern has been focused on animal production systems as a major nonpoint source of pollution. These studies were conducted to further our understanding of whole-animal N metabolism, N excretion, and its partition between feces and urine in growing dairy heifers. Isocaloric diets [2.31 Mcal of metabolizable energy (ME)/kg ...

We hypothesized that stearoyl-CoA desaturase (SCD) enzyme activity would not correlate with fatty acid indices of SCD activity in steers fed different grains. Forty-five Angus steers (358 +/- 26 kg BW) were individually fed for 107 d diets differing in whole cottonseed (WCS) supplementation (0, 5, or 15% of DM) ...

Feedlot producers could optimize the value of cattle in a given market grid if they were able to improve the uniformity of the body composition between cattle among loads. Allelic variation due to a single nucleotide transition (cytosine [C] to thymine [T] transition that results in a Arg25Cys) has been ...

Two experiments were conducted to determine whether elevating the percentage of ruminally undegradable protein (RUP) in the diet would influence the RUP value of the protein feedstuff. A single-effluent, continuous-culture study was designed to test the effect of RUP inclusion rate in the diet on ruminal degradability of the protein. ...

Sixteen yearling bulls were utilized to investigate administration of ergotamine tartrate on semen parameters, fertilization, and endocrinology. Bulls were allotted to a control diet of cracked corn, corn silage, and soybean meal (CON, n = 8) or a diet supplemented daily with 40 microg/kg body weight of ergotamine tartrate (ET, ...

Three experiments were conducted to determine the effects of cattle age and dietary forage level on the utilization of corn fed whole or ground to feedlot cattle. In Exp. 1, 16 steers were used to investigate the effects of cattle age and corn processing on diet digestibility. Two cattle age ...

Methane emitted from the livestock sector contributes to greenhouse gas emissions worldwide. Understanding the variability in enteric methane production related to diet is essential to decreasing uncertainty in greenhouse gas emission inventories and to identifying viable greenhouse gas reduction strategies. Our study focused on measuring methane in growing beef cattle ...

The effects of propylene glycol (PEG) on performance, ruminal fermentation, blood glucose and insulin, carcass traits, and abundance of IGF-1 mRNA in LM and leptin mRNA in adipose tissue were examined in 20 Korean native steers, with 10 each in control and PEG-fed groups, respectively. Propylene glycol mixed with concentrate ...

The effect of dietary energy and weight class on the fertility of yearling beef heifers (Angus, Hereford, and Angus x Hereford) was investigated over 2 years. In year 1, heifers (n=58) were classed as heavy (HW; > or =340 kg) or light weight (LW; <340kg) and then assigned to receive ...

A feeding trail was conducted at Adami Tulu Research Center on Arsi-Bale weaned kids to see the effect of different levels of concentrate supplementation and determine optimum level of supplementation. Grazing kids were supplemented with four different levels (0, 150, 300, and 450 grams) of concentrate. Kids supplemented with high ...

A series of experiments was designed to test the ability to induce precocious puberty in heifers and to determine the underlying mechanisms responsible for the precocious attainment of puberty. A model consisting of early weaning (3-4 months of age) and feeding a high-concentrate diet was used for each experiment. This ...

We hypothesized that carcass and fatty acid composition of Angus and Japanese Black (Wagyu) steers would not differ if the steers were fed to a typical US. final weight, but that Wagyu steers fed to a typical Japanese endpoint body weight would have greater quality grades and softer fat than ...

The effects of feeding regimen on carcass characteristics, meat colour and water-holding capacity of M. liongissimus were studied in 24 female fallow deer (Dama.dama). All animals were farm raised; twelve were grazed on pasture and twelve were fed barley and a small amount of hay prior to slaughter. The animals ...

Five hundred seven bull calves were assembled at a commercial feedlot in North-central Utah and sorted by frame size into 8 pens. Bullocks were fed a high energy diet ad libitum. Approximately one-half of the bullocks received 27.5 mg/kg of sodium lasalocid daily while the others were fed 27.5 mg/kg ...

Effects of pasture- or mixed-diet finishing mode on colour and lipid stability were measured in meat from Charolais steers, heifers and cows of different ages after refrigerated storage. Meats from pasture- and mixed-diet finished cattle have more or less significant differences in lipid composition which will influence the colour and ...

The objective of this study was to characterize facial whorl characteristics in Holstein stud bulls (n = 485) and to investigate their association with measures of semen quantity and quality. Bulls had 1 (n = 454), 2 (n = 21) or no facial hair whorls (n = 5). Some 39% ...

The objective of this experiment was to provide a current evaluation of the seven most prominent beef breeds in the United States and to determine the relative changes that have occurred in these breeds since they were evaluated with samples of sires born 25 to 30 yr earlier. Carcass (n ...

AIM: To determine the effect of different carbohydrate-based finishing diets on fermentation characteristics and the shedding of Escherichia coli and enterohaemorrhagic E. coli (EHEC) virulence genes in cattle faeces. METHODS AND RESULTS: The size of faecal E. coli populations and fermentation characteristics were ascertained in three experiments where cattle were ...

To measure the effects of dietary fat on feedlot performance, carcass characteristics, and beef appearance, moisture binding, shelf life, and palatability, 168 crossbred beef steers (317 +/- 1.0 kg) were allotted randomly, within weight blocks, to a randomized complete block design with a 3 x2 + 1 factorial arrangement of ...

One hundred sixty-eight crossbred steers (317.1 +/- 1.0 kg) were used to evaluate the effects of supplemental fat in finishing diets on the fatty acid composition, including the 9,11 isomer of conjugated linoleic acid, of beef. Steers were allotted within three weight blocks to a randomized complete block design with ...

Two finishing trials were conducted to determine the effects of adding different types of corn bran, a component of corn gluten feed, on cattle performance. In Trial 1, 60 English crossbred yearling steers (283 +/- 6.7 kg) were used in a completely randomized design with four dietary treatments. Treatments were ...

Effects of three environments and their native or rye pasture forage systems on subsequent carcass characteristics, composition, and meat palatability were examined following grain feeding. Calves (F2 Angus x Bos indicus) with similar pre-weaning management and genetics were randomly assigned to one of eight treatments (McGregor-Calf; McGregor-Low; Uvalde-Low; Uvalde-High; Overton-Low, ...

Rapid body growth during the prepubertal period may be associated with reductions in mammary parenchymal growth and subsequent milk yield. The objective of this study was to test effects of dietary rumen-undegradable protein (RUP) and administration of recombinant bovine somatotropin (bST) during the prepubertal period on mammary growth and milk ...

Two taste preference studies were conducted using six Holstein heifers in each experiment to determine preferences for no ionophore, lasalocid, or monensin in the diet. In Exp. 1, individually penned (approx. 5 mo old; 220 +/- 14 kg BW) heifers were fed a basal total mixed ration containing 46% corn ...

The objectives of this study were to determine the effect of recombinant bovine somatotropin (bST) and added dietary rumen undegradable protein (RUP) on organ and tissue weights and body composition in growing dairy heifers. Thirty-two Holstein heifers were in the experiment, 8 killed initially at 3 mo of age, with ...

Selection for growth and improved carcass merit has resulted in cattle that are variable in composition of gain during the finishing phase. This study assessed the relative performance among cattle with different levels of initial backfat thickness. It also exploited the ability to track carcass composition in the live animal ...

Research was conducted to determine whether fluctuations in the amount of feed delivered and timing of feeding affect ruminal pH and growth of feedlot cattle. In Exp. 1, the effects of constant (C) vs. fluctuating (F) daily feed delivery on ruminal pH were assessed in a crossover experiment (two 28-d ...

Three experiments were conducted to evaluate management strategies designed to decrease heat stress of cattle finished during the summer. In Exp. 1, 144 Angus crossbred yearling steers were assigned to three treatments: 1) ad libitum access to feed at 0800 (ADLIB); 2) fed at 1600 with feed amount adjusted so ...

The objective of this study was to evaluate the influence of lipoic acid (LA) on beef LM steak bloom time, as well-as to characterize bloom time in the CIE L*, a*, and b* color space over a 93-min period. Thirty-two Simmental steers were supplemented with LA for 21 d immediately ...

Sixty Angus-cross steers were used to compare the effects of recycled poultry bedding (RPB) stacking method and the inclusion of monensin in growing diets on performance. Steers were individually fed balanced, growing diets for a period of 84 d. The diets were control (CON), CON + monensin (CON+M), deep-stacked RPB ...

Ascophyllum nodosum (Tasco-14) decreased the prevalence of enterohemorrhagic Escherichia coli (EHEC) O157:H7 in animals fed prior to harvest. Tasco-14 was supplemented on a 2% dry matter basis 14 days prior to harvest to determine its effects on EHEC and Salmonella spp. prevalence. Two hundred mixed crossbred steers and heifers (Bos ...

Two finishing experiments were conducted to determine the effects of concentration (Exp. 1) and composition of wet corn gluten feed (Exp. 2) in steam-flaked corn-based diets on feedlot steer performance. In Exp. 1, 192 English x Continental crossbred steer calves (299 +/- 0.6 kg) were used in a completely randomized ...

The value of sunflower seed (SS) in finishing diets was assessed in two feeding trials. In Exp. 1, 60 yearling steers (479 +/- 45 kg) were fed five diets (n = 12). A basal diet (DM basis) of 84.5% steam-rolled barley, 9% barley silage, and 6.5% supplement was fed as ...

The objective of this study was to determine the effect of type of conserved forage and concentrate composition on the quality of beef held in overwrapped (aerobic) or modified atmosphere packaging under simulated retail display for 17 d. Friesian steers (n = 45) were assigned randomly to one of five ...

Angus x crossbred heifers (270 per trial) were used in an experiment conducted over one 105-d summer and one 104-d winter feeding period. Treatments were identical for each trial and included: 1) control, 2) estrogenic implant (E), 3) trenbolone acetate implant (TBA), 4) E + TBA (ET), 5) melengestrol acetate ...

Eight weaned Holstein steers approximately 4 mo of age (mean BW = 119.47 ± 2.65 kg) were used in a replicated 4 x 4 Latin square designed experiment to study the effects of protein source and level on performance and anabolic hormonal status of weaned dairy calves. Treatments consisted of ...

The efficacy of replacing broiler litter with rice mill feed was evaluated in four experiments. In Exp. 1, 40 predominantly Angus steers (initial BW = 277+/-18.2 kg) were fed four dietary treatments for 112 d (five steers per pen; two pens per diet). Dietary treatments (DM basis) were as follows: ...

Three finishing trials were conducted to determine the effects of dietary manipulation and management on N losses from open feedlots. In each experiment, 96 steers were assigned randomly to 12 nutrient balance pens. In Trial 1, calves were fed for 180 d during the winter/spring months; in Trial 2, yearlings ...

A long-term study was performed on the prevalence of enterohemorrhagic Escherichia coli (EHEC) O157 in bovine faeces. The present study was conducted on heifers raised on a farm showing a high isolation rate of EHEC O157 in previous years. The prevalence of EHEC O157 isolated from faecal samples was 10.6% ...

This study evaluated the effect of barley varieties in the diets of finishing steers on carcass composition, fat, and lean color and the fatty acid profile of subcutaneous fat. Crossbred steers (391 kg initial BW) were assigned randomly to one of five finishing diets composed primarily of corn (n = ...

The hypothesis of this experiment was that increasing dietary fat through the use of whole oilseeds and altering the dietary ratio of PUFA:saturated fatty acids would alter carcass composition of finishing steers. Seventy-two steers (443.6 +/- 1.0 kg) were fed for 76 d one of four dietary treatments: a corn/ ...

Angus steers of known age (265 +/- 17 d) and parentage were used in a 2-yr study (yr 1, n = 40; yr 2, n = 45) to evaluate the relationship between percentage of i.m. fat content of the longissimus dorsi at the 12th rib and carcass characteristics during growth ...

The somatotropic axis, consisting of growth hormone (GH), GH receptor (GHR), insulin-like growth factor (IGF)-I, IGF binding proteins (IGFBP), and IGF receptors, controls growth and mammary development in heifers. Manipulation of the axis with recombinant bovine somatotropin (rbST) improves heifer growth and reduces age at first calving. The effects of ...

Sixteen pregnant Holstein heifers weighing 521 +/- 46 kg, at 3.3 +/- 0.7 months of gestation and 2.2 +/- 2.0 months of age were confined to wooden metabolism cages and were exposed to a vertical electric field (EF) of 10.0 +/- 0.4 kV/m and an artificial light cycle of 12 ...

The objective of this study was to describe the prevalence of Escherichia coli O157 in the feces and on the hides of finishing beef cattle fed a standard diet and those fed diets supplemented with direct-fed microbials. Two hundred forty steers received one of four treatments throughout the feeding period: ...

The developmental patterns of carcass traits were studied in _ and 3/4 Boer x Malawi crossbred goats slaughtered at 30, 35 and 40 kg live weights. Empty body, hot and cold carclass weights, and head proportions differed among the three slaughter groups. There were no significant differences in carcass and ...

Effective preharvest control measures for Escherichia coli O157:H7 in cattle may significantly reduce the incidence of human disease caused by this organism. The prevalence and magnitude of fecal E. coli O157:H7 excretion was evaluated in 15 pens (300 to 500 cattle per pen) of commercial feedlot cattle fed a barley-based ...

Six ruminally cannulated Angus-cross steers (362 kg) were used in a replicated 3 x 3 Latin square design to determine effects of supplementing Maillard reaction products (MRP) on acid-resistant E. coli and coliform populations. Steers were fed roughage-based diets supplemented (DM basis) with either 10% soybean meal (SBM), 10% nonenzymatically ...

The objective of this study was to evaluate attributes in semitendinosus muscle (ST) associated with tenderness in divergent breeds--Wagyu (W; n = 12), Limousin (L; n = 12), and Wagyu x Limousin cross cattle (WxL; n = 12)--fed two dietary treatments (0 or 6% sunflower oil, DM basis). A randomized ...