Abstract The objective of this study was to evaluate the effect of increasing levels of spineless cactus (SC) [Nopalea cochenillifera (L.) Salm Dyck] on nutrient intake, ingestive behaviour, and performance of lambs in a feedlot. Thirty-two male (non-castrated) Santa Inês lambs with a mean initial body weight (BW) of 20.4 ± 2.60 kg were distributed across four levels of spineless cactus: zero, 24, 52, and 75% of total diet dry matter (DM). Over 56 days, the animals had their intake and performance monitored. The inclusion of SC influenced (p<0.05) in a quadratic way the dry matter intake and total digestible nutrients, but linearly decreased (p<0.05) the neutral detergent fiber intake. Drinking water intake decreased linearly (p<0.05) with the inclusion of SC in the diet. The inclusion of SC influenced (p<0.05) in a quadratic way the digestibility of organic matter in the diet. The increase in the level of SC in the diet increased linearly (p<0.05) the feeding and rumination efficiencies of the lambs. The maximum daily gain of 0.237 kg/day was achieved with 44% SC in the diet. It is recommended to include up to 40% of spineless cactus in the diet of lambs.

ABSTRACT In semi-arid zones, feedlots are considered a tool to minimize the impacts of seasonal forage on the production of sheep meat in the tropics. However, the use of alternative tropical ingredients as substitutes for corn (Zea mays L.) and soybean (Glycine max [L.] Merr.) meal in formulations of confined sheep diets is recurrent. The aim of this study was to evaluate the effect of diets containing corn and soybean meal (CS), corn (CU), cassava (Manihot esculenta Crantz) root (CRU) or spineless cactus (Opuntia ficus-indica [L.] Mill., SCU) associated with urea on the performance, carcass characteristics and meat quality of confined lambs. Forty non-castrated Santa Inês sheep with average age of 150 d and average initial weight of 22.6 ± 2.3 kg were confined in individual pens for 76 d and slaughtered. The diets effects were contrasted by Tukey test. Empty body weight was different among the treatments (P < 0.05) and was 27.3, 25.3, 23.0 and 21.1 kg for the animals fed CS, CU, CRU and SCU, respectively. CS diet presented higher cold carcass weights while SCU diet presented lower cold carcass weights (P < 0.05) (11.37 kg) and higher cooling losses. Luminosity, yellow color intensity and meat moisture content were higher (P < 0.05) in SCU than CS. Liver, skin and internal fat weights were similar (P > 0.05) in CU and CRU, but higher (P < 0.05) than SCU. The replacement of corn and soybean meal for different carbohydrate sources associated with urea reduces the body weight components in confined sheep.

Resumo: Objetivando-se avaliar o efeito da adição de palma forrageira associado à maniçoba na dieta de ovinos sobre o perfil de indicadores bioquímicos do metabolismo energético e proteico, foi realizado um delineamento em blocos casualizados onde foram utilizados 24 ovinos machos, sem padrão racial definido, com peso corporal médio de 19,77±1,95 kg e idade média de seis meses, divididos igualmente em três tratamentos: concentrado + feno Tifton 85, concentrado + feno de maniçoba e concentrado + silagem de maniçoba, e semelhantes partes de palma forrageira. Realizaram-se quatro coletas de sangue, que constituíram as repetições, com intervalos de 15 dias (0d, 15d, 3d0 e 45d). Em seguida, procederam-se as análises dos seguintes indicadores bioquímicos: creatinina sérica, ureia, proteína total, albumina, globulina, glicose, frutosamina, aspartato aminotransferase, fosfatase alcalina, gama glutamiltransferase, sódio, potássio, cloro, cálcio e fósforo. Maior consumo de matéria seca foi observado no grupo com feno de maniçoba. O tratamento com silagem de maniçoba apresentou diferença (P<0,05) no consumo de fibra em detergente neutro. Houve variações significativas na concentração de ureia nos animais que receberam a dieta composta de feno de maniçoba. Tanto o feno como a silagem de maniçoba, em até 30%, pode substituir o feno de Tifton 85 na alimentação de ovinos em terminação, mantendo efetivamente o consumo de matéria seca, rendimento de carcaça, os metabolismos proteico, energético e mineral, além de ser uma boa alternativa para a alimentação de ovinos.

Abstract: Aiming to evaluate the effect of addition of cactus pear associated with maniçoba in the diet of sheep on the profile of biochemical indicators of energy metabolism and protein, we performed a randomized block design was used in which 24 male sheep without defined breed (SPRD), mean weight of 19.77±1.95 kg and average age of six months, divided equally into three treatments: concentrate + Tifton hay, concentrate + maniçoba hay and concentrate + maniçoba silage, and similar parts of cactus pear. There were four blood samples, which were repetitions at intervals of 15 days (0d, 15d, 3d and 45d). Then proceeded to the analysis of the following biochemical parameters: serum creatinine, urea, total protein, albumin, globulin, glucose, fructosamine, aspartate aminotransferase, alkaline phosphatase, gamma glutamyl transferase, sodium, potassium, chlorine, calcium and phosphorus. Higher dry matter intake was observed in the group with maniçoba hay. Treatment with maniçoba silage showed statistical differences (P<0.05) in the consumption of neutral detergent fiber. Significant variations were found in the concentration of urea in the animals fed the diet composed of maniçoba hay. Both hay and silage maniçoba, up to 30%, can replace the Tifton 85 hay for feeding finishing animals, effectively keeping the dry matter intake, carcass yield, the protein metabolism, energy and mineral, plus be a good alternative for feeding sheep.