Michelle Christina Bernardo de Siqueira

Performance of lambs fed alternative protein sources to soybean meal

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.

Substituição do fubá de milho por gérmen integral de milho na dieta de ovinos

O objetivo deste trabalho foi avaliar o efeito da substituicao do fuba de milho pelo germen integral de milho, sobre a digestibilidade dos nutrientes na dieta e sobre o desempenho e caracteristicas de carcaca de ovinos Santa Ines. Quarenta animais, com peso inicial de 17,0±2,5 kg, foram confinados em baias individuais, em delineamento de blocos ao acaso, com cinco tratamentos e oito repeticoes. As taxas de substituicao foram: 0, 25, 50, 75 e 100%. Ao abate, foram obtidos os pesos de carcaca quente e de trato digestivo cheio e vazio, a area de olho de lombo, a espessura de gordura subcutânea e o rendimento de cortes comerciais. A substituicao do fuba de milho pelo germen integral reduziu linearmente o consumo de materia seca e os coeficientes de digestibilidade de: materia seca, materia orgânica, proteina bruta, fibra em detergente neutro e extrato etereo. A conversao alimentar nao foi afetada pelos tratamentos. O ganho medio diario, o peso vivo final, a area de olho de lombo, a espessura de gordura e os rendimentos de carcaca quente e de cortes comerciais diminuiram linearmente com o aumento nos niveis de substituicao. A substituicao do fuba de milho pelo germen integral de milho, nas dietas de ovinos, prejudica o desempenho e as caracteristicas de carcaca dos animais.

Carcass characteristics of sheep fed with castor bean hulls in replacement of tifton 85 hay

Castor bean hulls (CBH), co-products of castor oil extraction, are high in dry matter (DM) and fiber and are emerging as alternative roughage in sheep feed. This could reduce feed costs since other sources of roughage can be more expensive. The effects of replacing Tifton 85 hay with CBH at 0, 33, 66 and 100% in the diet of sheep on the carcass characteristics, weights and yields of retail cuts and carcass measurements were studied. Twenty-eight non-castrated sheep averaging 7 ± 1.4 months of age with an initial weight of 19.5 ± 4.3 kg were slaughtered after 70 days of confinement. There was a linear decline (P ≤ 0.05) in slaughter body weight, empty body weight, hot and cold carcass weight and longissimus muscle area (LMA) as the percentage of dietary CBH increased. A linear decrease (P≤0.05) of the weights of all retail cuts and a quadratic effect (minimum yield of 9.84% with the replacement of 56.9%) of the neck yield were also detected as the percentage of CBH increased. No treatment effects (P > 0.05) on the yield of the other cuts were observed, but there was a linear decline (P ≤ 0.05) in the perimeters of the thorax, leg and rump and the carcass compactness index. Replacing Tifton 85 hay with CBH in sheep diets is not recommended because it decreases the slaughter body weight, cold and hot carcass weight, retail cut weights and morphometric measurements.

Replacement of wheat bran with spineless cactus in sugarcane-based diets for steers

The effect of replacing wheat bran with spineless cactus (0, 25, 50, 75, and 100%) in sugar cane-based diets on the intake of nutrients, feeding behavior, and rumen digestibility of steers was assessed using digested samples collected from the omasum. Five crossbred steers (1/2 Holstein-Zebu) were fitted with cannulas in the rumen and then assigned to a 5 × 5 Latin square design. Samples of omasal digesta were collected for three days. Rumen was evacuated via the rumen cannula to determine the rumen pool of dry matter (DM), neutral detergent fiber (NDF), indigestible NDF (iNDF), intake (ki), passage (kp) and degradation (NDF) rates, and the passage of iNDF (kpi). Nutrient intake displayed a quadratic effect, with maximum intakes of DM (5.73 kg d−1), non-fiber carbohydrates (NFC, 4.63 kg d−1), and digestible organic matter (DOM, 3.45 kg d−1) estimated at the replacement levels of 54.63, 60.00, and 43.17%, respectively. The replacement levels showed no effect on feeding, rumination, or idle times. There was a linear increase in the total apparent and ruminal digestibility of CP as the spineless cactus content in the diet was increased. There was no effect on total and partial digestibilities of OM and NDF or on intestinal digestibility of CP. No effect was observed on the rumen pool of DM, NDF, or iNDF. Furthermore, ki, kp, NDF degradation, and iNDF passage rates displayed a quadratic effect, with higher concentrations estimated for replacement levels of 56.07, 56.12, 59.00, and 55.20%, respectively. Replacing 55% wheat bran with spineless cactus in sugar cane-based diets is recommended.