No abstract

-The objective of this study was to evaluate the effect of alternative protein sources (castor bean cake, sunflower cake, and sunflower seed) to soybean meal on the intake and performance of 40 lambs, initially weighing 19.8±1.84 kg, fed diets based on Tifton grass hay. The experimental design was completely randomized blocks. There were no differences in the nutrient intake of castor bean diets compared with soybean meal. The intake of nutrients in the sunflower cake and sunflower seed diets was decreased compared with soybean meal. The apparent digestibility coefficients of dry matter, organic matter, crude protein, and neutral detergent fiber of sunflower cake and sunflower seed diets were decreased compared with soybean meal. The average daily weight gain of animals fed the castor bean diet (0.190 kg) was not different from that of the animals fed the soybean meal diet (0.217 kg). The sunflower cake and sunflower seed diets provided less weight gain (0.171 and 0.135 kg d -1 , respectively) than soybean meal due to the lower nutrient intake. The hot carcass yield and true yield were not affected by the protein sources. The neck, ribs, and ham weights were similar in lambs fed soybean meal and castor bean cake diets. It is recommended to use castor bean as an alternative protein source in the diet of lambs.

This study aims to evaluate the effect of the Tifton 85 hay (Cynodon dactylon L. Pers) replacement by Orelha de Elefante Mexicana spineless cactus (Opuntia stricta [Haw.] Haw) on the nutrient intake and digestibility, growth performance, microbial protein synthesis, and efficiency of dietary nitrogen compound utilization in the diets of Girolando heifers. Twenty-four (3.5 months and 100 kg ± 3.5 kg) Girolando heifers (5/8 Holstein x Gyr) were used and arranged in a completely randomized design. Dry matter, organic matter, crude protein, and neutral detergent fiber decreased linearly as a function of the levels of Tifton hay (TH) replacement by Orelha de Elefante Mexicana spineless cactus (OEM). The non-fiber carbohydrate intake and coefficient of dry matter digestibility increased, while the neutral detergent fiber (NDF) digestibility decreased linearly with the OEM inclusion. After evaluating the growth performance by observing weight gain and morphometric measurements, there were no significant alterations. The urinary volume, nitrogen balance as well as the efficiency of nitrogen retention had increased, while the urinary and plasma urea concentrations had decreased linearly with the OEM inclusion. The results obtained in this study show that Orelha de Elefante Mexicana spineless cactus should replace Tifton hay in post-weaned heifer diets.

<p>Objetivou-se avaliar o efeito de diferentes proporções de concentrado e bagaço de cana-de-açúcar como volumoso exclusivo em dietas para ovinos. Os consumos de matéria seca, matéria orgânica, proteína bruta, carboidratos não fibrosos e nutrientes digestíveis totais expressos em kg/dia, aumentaram linearmente com o aumento da proporção de concentrado na dieta. O mesmo comportamento foi observado para a digestibilidade da matéria seca. O que ocorreu de forma contrária para a digestibilidade da fibra em detergente neutro, que diminuiu com os maiores níveis de concentrado. Com o aumento das proporções de concentrado nas dietas experimentais, foi observado efeito quadrático no tempo despendido com ruminação, alimentação e ócio, e nas concentrações de ácido acético, propiônico e butírico no rúmen. Maiores proporções de concentrado associado ao bagaço de cana-de-açúcar <italic>in natura</italic>podem ser utilizadas em dietas para ovinos.</p>

Context Supplementation during the pre- and post-weaning periods is essential to improve the development of beef heifers in tropical pastures. Especially during the dry period, performance of heifers is limited due to low forage yield and poor nutritional value. Aim Evaluate the effect of supplementation during pre- and post-weaning periods on performance, nutritional, and metabolic characteristics in Nellore heifers under grazing. Methods Fifty-four Nellore heifers were randomly divided between the following four supplementation plans, with two replicates: NN, not supplemented in the pre- and post-weaning dry period; NS, not supplemented in the pre-weaning period and supplemented in the post-weaning dry period; SN, supplemented in the pre-weaning period and not supplemented in the post-weaning dry period; and SS, supplemented in the pre- and post-weaning dry periods; with 14, 13, 13 and 14 calves in each treatment respectively. In the post-weaning dry-to-rainy transition period, all heifers were supplemented. Key results Supplementation increased (P < 0.05) the intake of dry matter and crude protein on Day 56 (pre-weaning phase) and Day 168 (post-weaning dry period). Heifers supplemented during the pre-weaning phase had a higher final body weight (fBW) and average daily gain (ADG) on Day 112 (P < 0.05). Heifers NS and SS had higher fBW and ADG on Day 224 (P < 0.05). On Day 280, fBW were higher (P < 0.05) for heifers NS and SS. Insulin-like growth factor 1 was higher for heifers supplemented in the pre-weaning period on Day 112, and higher for NS and SS heifers on Day 224 (P < 0.05). Albumin concentrations were higher (P < 0.05) for heifers NS and SS on Day 280. Supplementation had no effect on either corpus luteum presence or concentration of progesterone (P > 0.05). Conclusions Supplementation during either pre- or post-weaning phases improved multiple performance, nutritional, and metabolic characteristics. The results due to supplementation post-weaning were independent of supplementation pre-weaning. However, supplementation did not result in an improved response to the puberty induction protocol used in this experiment. Implications For replacement heifers, it is important to maintain high weight gains at all stages of growth.