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This work aimed to survey management practices used by dairy farmers and to report nutritional recommendations adopted by 43 dairy cattle nutritionists in Brazil. The web-based survey consisted of 80 questions. Almost 50% of the participants had clients that produce <1000 kg of milk daily and 48.8% had clients who own fewer than 100 dairy cows. Corn was the primary source of grain (97.4%), and 43.9% of the nutritionists included from 41% to 50% concentrate in lactation diets. The mean roughage inclusion in lactation diets was 50.5% and 79% of the nutritionists reported corn silage as the primary roughage source. Average crude protein and rumen-degradable protein concentrations recommended by the nutritionists for lactation diets were 15.7% and 9%, respectively. Average Ca and P concentrations recommended for lactation diets were 0.70% and 0.41%, respectively. The major health problem reported by 83.9% of the nutritionists was mastitis. The present survey provides an overview of management practices adopted by dairy farmers and nutritional recommendations currently applied by dairy cattle nutritionists in Brazil. The most critical points identified were low milk yield, mastitis as the major health problem, lack of proper mixing and delivery of rations, and destination of male calves.

The experiment was designed to determine the effects of different doses of sodium monensin (MON) on feeding behaviour, dry matter intake (DMI) variation and selective consumption of feedlot Nellore cattle. The experiment was a randomised complete block design, replicated 12 times, in which 60 20-month-old yearling Nellore bulls (402.52 ± 33.0 kg) were fed the following different doses of MON (expressed in mg per kg, on a DM basis) in individual pens for 84 days: 0, 9, 18, 27 and 36. The adaptation program consisted of ad libitum feeding of two adaptation diets over a period of 14 days with concentrate level increasing from 68% to 84% of diet DM. Orthogonal contrasts were used to assess linear, quadratic, cubic and quartic relationships between doses of MON and the dependent variable. As the dose of MON increased, the time spent ruminating (P < 0.01), feeding efficiency of DM (P < 0.05) and feeding efficiency of neutral detergent fibre (NDF; P < 0.05) were affected linearly during the period of adaptation. For the finishing period, as the dose of MON increased, time spent eating and ruminating, and feeding efficiency of DM were affected quadratically (P < 0.05), in which animals fed 9 ppm of MON presented better feeding efficiency of DM. Thus, as animals fed 9 ppm of MON presented better feeding efficiency of DM and NDF during the adaptation and finishing periods, it should be the dose of choice for feedlot Nellore cattle.

Owing to the lack of information in the literature about the ideal feeding frequency adopted by feedlot systems, this study was designed to evaluate the effect of different feeding frequencies on performance, carcass traits, feeding behavior and rumen morphometrics of Nellore cattle. Forty-eight yearling bulls were housed in individual pens with an average initial body weight of 358.2 kg. The experiment was designed as a completely randomized block and the treatments were the feeding of cattle one, two, three, or four times daily (n = 12 per treatment). Orthogonal contrasts were used to assess linear, quadratic and cubic relationship between feeding frequency and the dependent variable. As feeding frequency increased, final body weight (p = 0.03) and average daily gain (p = 0.01; one: 0.98 kg d-1 ; two: 0.96 kg d-1 ; three: 1.18 kg d-1 ; four: 1.14 kg d-1) increased linearly and the feed:gain ratio decreased (p = 0.02). Also, as feeding frequency increased, hot carcass weight was affected cubically (p = 0.01; one: 246.9 kg; two: 243.0 kg; three: 263.1 kg; four: 258.1 kg). During the adaptation period dry matter intake variation was affected cubically (p ≤ 0.05; one: 16 %; two: 23 %; three: 14 %; four: 16 %). Increases in feeding frequency affected papillae height (p < 0.01) and papillae surface area (p < 0.01) cubically, as well as producing increases in the mitotic index (p = 0.05; one: 9 %; two: 11 %; three: 13 %; four: 13 %) and cells in proliferation (p = 0.05) linearly. Thus, Nellore yearling bulls should be fed three times daily in feedlot operations.

The objective of this study was to evaluate the addition of cane molasses during a 60 day dry period on performance and metabolism of Holstein cows during prepartum and postpartum periods. For experiment 1, 26 primiparous and 28 multiparous cows were used. Upon freshening, all cows were offered a common lactation diet. For experiment 2, six multiparous cows fitted with rumen cannulas were used to measure performance and metabolism, following the same protocol as experiment 1. Ruminal propionate increased by 10% during both prepartum and postpartum periods; however, papillae area was greater for cows not fed molasses, and volatile fatty acids (VFA) absorption from the rumen was not increased, resulting in similar glucagon-like-peptide-2 receptor (GLP-2R) density. The improved dry matter intake, when molasses was added into prepartum diets, translated into increased milk yield and energy-corrected milk (ECM) in Experiment 1 only for multiparous cows. For experiment 2, the improvement on milk performance was also observed, where cows fed molasses had 18.5% greater ECM production. Feeding molasses during a 60 day dry period positively influenced transition cow performance, and it was not accompanied by changes in rumen morphometrics; however, this indicates enhanced adaptation by the rumen epithelium based on similar capabilities for VFA absorption.

The objective of this study was to evaluate performance of lambs when supplemented with different doses and forms of tributyrin in moderate (MF) and low forage (LF) diets. Eighty-four ram lambs were blocked by initial BW (27.9 ± 2.3 kg) assigned into 1 of 2 groups that were fed a MF (40% forage) or LF (10% forage) diet (%DM). Lambs in each block were also assigned to 1 of 6 treatments (n = 7) including a control (no supplementation) or diets that contained 0.1, 0.2, or 0.3% (DM basis) rumen protected (RPT) or 0.1 or 0.3% of tributyrin that was not protected (NPT). Lambs were housed indoor in individual pens and fed once daily for 97 d. At harvest, hot carcass weight (HCW) and back-fat thickness was measured for each lamb. Within diet type (MF and LF), data were analyzed to determine the linear and quadratic response for increasing RPT, the effect of using tributyrin (con vs. RPT and NPT), and the effect of rumen protection (RPT vs. NPT). Treatments fed MF diets did not differ with each other (P ≥ 0.06) for final BW (53.5 kg), ADG (255 g/d), DMI (1.42 kg/d), gain:feed ratio (0.187 kg/kg), backfat thickness (14.1mm), hot carcass weight (24.0 kg), and dressing percentage (45.0%). Also, no differences (P ≥ 0.08) were detected for final BW (56.0 kg) and ADG (0.30 kg/d), DMI (1.56 kg/d), gain:feed ratio (0.190 kg/kg), back-fat thickness (16.8 mm), and HCW (25.5 kg) between treatments fed LF diets. However, lambs fed LF diet with RPT had greater (P = 0.04) dressing percentage than lambs fed NPT (45.9 vs. 44.5%, respectively). We conclude there is no benefit from inclusion of tributyrin in MF diets for lambs whether provided in protected or unprotected form. However, feeding RPT in LF diets for lambs may enhance dressing percentage.