Ruminal acidosis challenge impact on ruminal temperature in feedlot cattle

The objective of this experiment was to determine if ruminal temperature rise coincides with pH reduction using an acidosis challenge model. Twelve ruminally cannulated steers (518 ± 28 kg BW) were administered ruminal temperature-monitoring devices that recorded temperature every 2 min. Steers were fed a 63% concentrate diet at 1.6% BW for 20 d before being randomly assigned to 1 of 3 acidosis challenge treatments: no dietary change (CON), onehalf of daily DMI replaced with cracked corn (HALF), or all of daily DMI replaced with cracked corn (CORN). The challenge was initiated by ruminally dosing steers with their treatment diets. Ruminal pH and rectal temperatures (Trec) were recorded every 3 h for 72 h. All steers were offered CON diets at 24 and 48 h after challenge. Ruminal pH showed a treatment × day effect (P = 0.01). Ruminal pH of CORN steers was lower (P = 0.03) than that of HALF steers on d 1, was lower (P ≤ 0.004) than that of HALF and CON steers on d 2, and tended to be lower (P ≤ 0.10) than that of HALF and CON steers on d 3. Treatment did not affect (P ≥ 0.42) RecT. Ruminal temperature (Trum) showed a treatment · d-1 × h-1 after feeding interaction (P < 0.01). At 3 h after challenge, Trum of CORN and HALF steers was higher (P ≤ 0.01) than that of CON steers. On d 2, Trum of CORN steers was higher (P ≤ 0.03) than that of CON between 6 and 12 h after feeding. From 15 to 21 h after feeding on d 2, Trum of HALF steers was higher (P < 0.01) than that of CORN and CON steers. On d 3, at the time of feeding until 3 h later, Trum of CORN steers was lower (P ≤ 0.04) than that of all other steers. Rectal temperature was correlated (P ≤ 0.01) with Trum on all days for CON and CORN steers. Ruminal pH was negatively correlated (P ≤ 0.04) with Trec on d 2 and Trum on d 1 in CORN steers, and Trum was negatively correlated (P ≤ 0.02) with ruminal pH in HALF and CON steers on d 1 and 3, respectively. The amount of time above Trum of 39.0°C or 39.45°C was correlated (P ≤ 0.05) with the time spent below a ruminal pH of 5.5 in CORN steers; however, time above Trum of 39.0°C did not differ (P = 0.87) among treatments. Results indicate that there is a negative relationship between Trum and ruminal pH during an acidotic episode; therefore, Trum monitoring can detect a potential acidotic episode. © 2012 American Society of Animal Science. All rights reserved.

Influence of stocking density on weight gain and behavior of feedlot lambs

The aim of this study was to verify the influence of the animal density on the weight gain and behavior of confined lambs. 86 animals were confined after weaning in 23 pens of two lambs each (double pens) and four pens of ten animals each (collective pens). During the 80 days of confinement all lambs received the same diet and the animals were weighed at the beginning of the trial and every 14 days for the control of the weight gain. The behavioral patterns were recorded by focal sampling method using a time sampling of 30 minutes, from 6:00 am to 6:00 pm, for 4 days. The behavioral variables were: posture (standing; lying), activity (eating; ruminating; leisure; drinking water; grooming) and events (nid-nodding; pushing; picking up; bellowing; mounting; defecating; urinating). For the evaluation of the weight gain and behavior of the animals an analysis of variance and multiple comparison procedure by Student t test was used. The average weight gain was higher for pen animals (0.228 kg/day) compared to the animals housed in the collective pens (0.208 kg/day; P = 0.07). A higher percentage of animals housed in double pens remained standing compared to the animals housed in collective pens at 8:30 am (P < 0.05), 11:30 am (P < 0.01), 2:30 pm (P < 0.01), 4:30 pm (P < 0.01), and 5:30 pm (P < 0.01). For the eating activity, it was observed that 6.9% more animals kept in the double pens remained in this activity at 8:30 am (P < 0.05) and 4:30 pm (P < 0.05), than in collective pen. No statistical difference was found for the other activities and events between treatments. The number of animals per group influenced the behavior of confined lambs, changing the pattern of food intake which could improve the weight gain. © 2013 Elsevier B.V. All rights reserved.

Carcass characteristics of feedlot lambs fed crude glycerin contaminated with high concentrations of crude fat

Thirty non-castrated male lambs with 20. ±. 2.3. kg average body weight (BW) were randomly assigned to five treatments consisted of different dietary concentrations of crude glycerin (CG; 0, 3, 6, 9 and 12% on DM basis) to evaluate the effects on performance, carcass and meat quality traits. A quadratic effect was observed for performance (P= 0.04), final BW (P<. 0.01) and hot carcass weight (P<. 0.01). No effects of CG were observed (P>. 0.05) on carcass pH neither on shear-force, cooking loss and ether extract content in longissimus. The inclusion of CG tended to reduce the Zn content in meat (P= 0.09). The data suggests that CG (36.2% of glycerol and 46.5% of crude fat) may be used in diets of finishing lambs with concentrations up to 3% without negative effects on performance and main carcass traits. Moreover, inclusion of CG seems to not affect quality and safety of meat for human consumption. © 2013 Elsevier Ltd.

Feedlot performance, carcass characteristics and meat quality of Nellore and Canchim bulls fed diets supplemented with vitamins D and E

O experimento foi conduzido no setor de confinamento da Unesp, campus de Botucatu, com o objetivo de avaliar a influência da suplementação das vitaminas D e E sobre o desempenho animal, características de carcaça e qualidade de carne de bovinos jovens confinados. Foram utilizados 36 machos inteiros, 18 Nelore (NEL) e 18 Canchim (CAC), de sete meses de idade com peso vivo inicial médio de 234,53 ± 22,15 e 248,13 ± 34,67 kg, respectivamente, os quais foram confinados por 126 dias. Nove animais NEL e nove CAC foram suplementados diariamente com 1300 UI de vitamina E e 7,5x10(6) UI de vitamina D3 durante 67 e dez dias antes do abate, respectivamente. Um dia antes do abate foram coletadas amostras de sangue para avaliação do cálcio plasmático. Na desossa, foram colhidas amostras do músculo Longissimus (LM) para análises como força de cisalhamento, índice de fragmentação miofibrilar, lipídeos totais, concentração de vitaminas D e E e tempo de prateleira. Foi observado aumento (p < 0,01) do nível de cálcio plasmático pela suplementação, o que indica atuação da vitamina D no organismo animal. No entanto, não houve efeito (p > 0,05) da suplementação de vitaminas D e E sobre o desempenho, características de carcaça e qualidade da carne.

Genome-wide association study for feedlot average daily gain in Nellore cattle (Bos indicus)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Immunocastration improves carcass traits and beef color attributes in Nellore and Nellore x Aberdeen Angus crossbred animals finished in feedlot

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of lipid sources with different fatty acid profiles on the intake, performance, and methane emissions of feedlot Nellore steers

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Allometry of Organs and the Gastrintestinal Tract from Water Buffaloes (Bubalus bubalis) Finished in Feedlot

The objective of present study was to evaluate the relative growth of organs and viscera from water buffaloes. Fifteen Mediterranean intact males, averaging, 356.7 kg initial live weight and twenty four months of age, were used. The animals were ramdomly assigned into three groups (categories). One group was ramdomly assigned to immediate slaughter (AR), the rest two groups were full-fed a ration containing 50% concentrate, dry matter basis until reaching the slaughter weights of 450 and 500kg, respectively. At slaughter the empty body weight was determined and the weights of head, feet, leather, lungs, heart, liver, spleen, rumen-reticulum, omasum, abomasum, small intestine, large intestine were recorded. Regression equations of log weight of organs and viscera as a function of log empty-body-weight (EBW), were fitted. All body components studied, with exception of liver and spleen, developed slower than in relation to EBW.

Performance and carcass quality of feedlot- or pasture-finished Nellore heifers according to feeding managements in the postweaning phase

The objective of this study was to evaluate the postweaning history of heifers kept on marandu grass pastures with three canopy heights, in a continuous-grazing system, during the rainy period, on feedlot-or pasture finishing. The effects of three canopy heights (15, 25 and 35 cm) associated with two supplements (mineral salt and protein-energy supplement) and two finishing systems in the dry period (feedlot and open pasture) were studied in the postweaning period during the rainy season. The adopted design was completely randomized, with seven replications (animals) in a 2 x 2 factorial arrangement. The animals which received protein-energy supplement reached the finishing period with greater body weight in relation to those fed mineral salt. In both feedlot and pasture finishing systems, compensatory gain effect was observed in the animals that remained on the low pastures during postweaning compared with the high pastures. This compensatory gain was not verified in the animals that received protein-energy supplement in relation to the mineral salt, and thus the animals were slaughtered beforehand. The heifers on pastures with 25 or 35 cm in height were slaughtered in the same period, and those kept on the low pastures were slaughtered afterwards. The studied factors in the postweaning phase did not affect the carcass characteristics. Animals finished in feedlot slaughtered with the same body weight as those finished on pasture show greater carcass yield, subcutaneous fat deposition and renal pelvic and inguinal fat and greater losses with trimmings for cleaning the main hindquarter meat cuts; however, they provide cuts with the same weight but greater fat cover.

Crude glycerin in diets for feedlot Nellore cattle

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Efficacy of sulfadoxine plus trimethoprim compared to management measures for the control of Eimeria parasitism in naturally infected and clinically asymptomatic sheep that were maintained in a feedlot

The efficacy of sulfadoxine + trimethoprim in comparison to management measures for the control of Eimeria parasitism was studied in naturally infected sheep that were raised in a feedlot and were clinically asymptomatic for eimeriosis. Weight gain was also evaluated in these animals. The following groups were formed with 15 animals/group: TO!, control animals that received saline solution and maintenance of the same management measures that were performed before the study; T02, animals that received two intramuscular doses of sulfadoxine (20 mg/kg) + trimethoprim (4 mg/kg) with a 14-day interval; T03, sheep that received two intramuscular doses of sulfadoxine (20 mg/kg) + trimethoprim (4 mg/kg) with a 14-day interval plus management measures (wood shaving bedding was changed every Monday, and 30g of ammonium sulfate were applied to the bedding and other facilities were performed every Thursday, 10 mL/20 L of water); and T04, animals that received only the management measures described for the previous group. The highest efficacy rates (arithmetic mean) for the T02 group (sulfadoxine + trimethoprim at days 0 and 14) were 21.04% and 21.98% on the 14th and 28th days after the first treatment (DAFT), respectively. However, the treatment showed efficacy rates below 17% and was totally ineffective from the 70th DAFT to the end of the study. In both the T03 (chemical treatment+ management) and T04 (management only) groups, a significant (P <= 0.05) reduction of oocyst shedding per gram of feces was observed in the animals from the 14th DAFT in comparison to the control group; however, an efficacy rate above 90% was observed from the 28th DAFT. Animals belonging to the T02, T03 and T04 groups presented with alterations in weight gain of 0.57 kg, 4.30 kg and 4.53 kg, respectively, in comparison with the control animals (T01) throughout the 91-day study period. Thus, it is possible to conclude that the two-dose sulfadoxine + trimethoprim treatment, given with a 14-day interval, had little no effect on the oocyst shedding. Moreover, the adopted management measures were enough to cause a significant decrease in the animal parasite loads. (C) 2013 Published by Elsevier B.V.

Survey of the nutritional recommendations and management practices adopted by feedlot cattle nutritionists in Brazil

Thirty-three feedlot cattle nutritionists were surveyed to evaluate the management practices and nutritional recommendations adopted by feedlots in Brazil. The web-based survey consisted of 81 questions that included: general information (n = 10); general commodity information (n = 15); use of coproducts (n = 5), roughage source and level (n = 5); adaptation methods (n = 7); feed mixers (n = 6); feeding management (n = 6); cattle management and type of cattle fed (n = 13); formulation practices (n = 9); information resources used for nutritional recommendations (n = 2); and additional questions (n = 3). In total, the 33 nutritionists were responsible for approximately 2,658,000 animals, and moreover, 65.5% of those participants had clients that feed less than 5000 animals yearly. Corn was the primary source of grain used in feedlot diets (87.9%) and cracking was the primary processing method recommended by nutritionists (57.6%). The average concentrate and roughage inclusion in finishing diets was 79.0% and 21.0%, respectively. The main challenges faced by nutritionists are the lack of available and precise equipment and lack of trained employees with respiratory diseases as the main health problem. This survey of nutrition and management practices should aid in the development of research for the feedlot industry in Brazil and similar tropical climates, as well as provide data to facilitate the broader application of future NRC models. (C) 2014 Elsevier B.V. All rights reserved.

Whole grain diet for Feedlot Lambs

For a lamb feedlot system became competitive it is essential that an equilibrate nutrition and functional feeding management happens naturally. Therefore, this experiment has the objective to evaluate the efficiency of whole corn grain diet on lambs performance and carcass quality parameters and ruminal papillae development. During the experiment twenty Dorper/Santa Inescrossbred lambs were used, divided randomly in two treatments: control diet and whole grain diet. The experimental design was completely randomized design and data analysis done by SISVAR using the Tukey test at 5% of probability. No statistical differences were observed on the characteristics evaluated for performance and carcass as well as the length and width of ruminal papillae. The composition of the diet together with the weight gain potential of the lambs can explain the good average daily weight gain of 0.284 kg. The initial body condition average was 2.1 (thin) and improved at the end of the trial period achieving3.15 (normal). Carcass yield reached 46.24%, the results is between the range ideal for specialty meat breeds ranging from 40 to 50%. The carcass conformation, fat cover conformation and the thickness of subcutaneous fat found can be classified as medians. Also there was no difference in the characteristics of ruminal papillae. Thus, it is concluded that the use of whole grain diet did not influence the characteristics evaluated; and the choice of diet should be made with regard to profitability, simplicity of use and availability of forage in feedlot. (C) 2014 Elsevier B.V. All rights reserved.

Effects of different doses of sodium monensin on rumen papillae and tissue histology of feedlot Nellore cattle

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Prediction of genomic-enabled breeding values and genome-wide association study for feedlot average daily weight gain in Nelore cattle

Pós-graduação em Genética e Melhoramento Animal - FCAV