This study evaluated the effect of feed restriction and goat genotype on meat quality. Three genotypes (Brazilian native breed Canindé; Brazilian native breed Moxotó; and F1 Boer crossbred animals obtained by crossing Boer bucks with local breed does) and three different feeding regimens (ad libitum fed, AL; restricted fed at 75% of the ad libitum, R.75; or restricted fed at 50% of the average ad libitum intake, R.50) were used. There was no difference (P>0.05) in chemical composition, total and soluble collagen, and shear force of the Longissimus lumborum muscle among genotypes. However, AL had greater amounts of soluble collagen and crude protein in the muscle (P<0.05) than R.75. No difference (P>0.05) was observed for the myofibrillar fragmentation index. The goat genotype presented few differences in their fatty acid profiles. However, goats fed ad libitum had a more favorable fatty acid profile for human health with greater concentrations of oleic acid, unsaturated fatty acids, and conjugated linoleic acid.

ABSTRACT. The objective of this study was to evaluate the effectiveness of reusing a controlled internal drug release (CIDR) device for up to three times in the reproductive performance of dairy goats raised in the semi-arid zone of northeastern Brazil. Forty-five goats were allocated into three hormone treatments, as follows: CIDR1x, treated with new CIDR during nine days. Two days prior to device removal, injections of 75 g d-cloprostenol and 300 IU equine chorionic gonadotropin (eCG) were administrated. For the other treatments, the same hormone protocol was used, differing only by the use of the same CIDR for a second time in CIDR2x and for a third time in CIDR3x. The interval from device removal to the onset of estrus (13.3  1.1h vs. 13.8  2.6h vs. 13.3  1.4h), as well as estrus duration (33.6  7.3h vs. 29.6  3.2h vs. 32.8  4.5h), did not differ (p > 0.05) among groups CIDR1x, CIDR2x and CIDR3x, respectively. All synchronized females were found to be in estrus. The overall fertility and prolificacy after artificial insemination were 82.2% and 1.9 kids, respectively, without significant difference (p > 0.05) among treatments. The use of the same CIDR for up to three times was effective using 9-day estrus synchronization protocols in dairy goats. RESUMO. Uso do mesmo CIDR por até três vezes para sincronização do estro e inseminação artificial de cabras leiteiras. Objetivou-se avaliar o efeito da utilização do mesmo dispositivo de liberação controlada de drogas (CIDR) por até três vezes sobre o desempenho reprodutivo de cabras leiterias exploradas no semiárido do Nordeste Brasileiro. Foram utilizadas 45 cabras divididas em três tratamentos de sincronização do estro, sendo: CIDR1x, tratadas com CIDR novo durante nove dias. Dois dias antes da retirada do dispositivo, foram aplicados 75 g de d-cloprostenol e 300 UI de gonadotrofina coriônica eqüina (eCG). Para os demais tratamentos, foi utilizado o mesmo protocolo hormonal, diferindo apenas pelo uso do mesmo CIDR pela segunda vez no grupo CIDR2x e uso pela terceira vez no grupo CIDR3x. O intervalo entre a retirada do dispositivo e o início do estro (13,3  1,1h vs. 13,8  2,6h vs. 13,3  1,4h), bem como, a duração do estro (33,6  7,3h vs. 29,6  3,2h vs. 32,8  4,5h) não diferiram (p > 0,05) entre os grupos CIDR1x, CIDR2x e CIDR3x, respectivamente. Todas as fêmeas sincronizadas foram identificadas em estro. As médias de fertilidade e prolificidade média após inseminação artificial foram, respectivamente, de 82,2% e 1,9 crias, não havendo diferença significativa (p > 0,05) entre os tratamentos. A utilização do mesmo CIDR por até três vezes foi viável na sincronização do estro de caprinos leiteiros.Palavras-chave: tratamento hormonal, pequenos ruminantes, região Tropical, dispositivos vaginais.

The aim of this study was to determine the energy and protein requirements of non-descript breed hair lambs (NDB) reared under Brazilian semiarid conditions. Sixty animals from three sex classes (20 intact males, 20 castrated males, and 20 females) with an average initial body weight of 18.1 ± 0.4 kg and an average age of 5 months were used. The nutritional requirements were estimated using the comparative slaughter. The animals in the final slaughter group were distributed in a completely randomized design with a 3 × 3 factorial scheme (three sex classes and three feeding levels: ad libitum feeding (positive energy balance), 70% feed restriction (maintenance level), and 80% feed restriction (negative energy balance)). The net energy requirement for maintenance (NEm) did not differ between sex classes (P > 0.05) and it was 68 kcal/kg of metabolic empty body weight (EBW(0.75))/day (P < 0.05). The coefficients for the nonlinear regression of retained energy (RE) on the empty body weight gain (EBWG) were not different among the different sex classes (P > 0.05). The net energy requirement for weight gain (NEg) was estimated by NEg (Mcal/day) = 0.29 × EBW(0.75) × EBWG(0.86) for all sex classes (P < 0.05). The net protein requirement for weight gain (NPg) was estimated by NPg (g/day) = 224.45 × EBWG - 0.025 × RE for all sex classes (P < 0.05). The NEg increased and the NPg decreased with the increase in body weight of NDB lambs.

The effect of different feeding levels (ad libitum, 25 and 50 % restriction) and genotypes (½ Boer × ½ nondescript breed goats, Canindé, and Moxotó) on carcass quantitative characteristics and non-carcass components (NCC) were evaluated. Forty-five intact male goats were distributed in a 3 × 3 factorial design with five replicates. There was no effect of genotype on carcass weights and yields and retail cuts weights and yields (P > 0.05). Compared to Moxotó, ½ Boer presented better carcass conformation and higher weights (P < 0.01) and yields of viscera from gastrointestinal tract (P < 0.05), and compared to the other genotypes (P < 0.01), ½ Boer presented larger carcass compactness. Carcass weights and yields, retail cuts weights and NCC, and soft tissues yields were higher (P < 0.01) in goats fed ad libitum. The two restriction levels did not differ (P > 0.05) for these variables. There were interactions of genotype and feeding level. At ad libitum feeding, ½ Boer had higher weights of breast and shank, leg, soft tissues, and gastrointestinal viscera compared to the Moxotó (P < 0.05). The crossing of nondescript breed goats with Boer may be a strategy for increasing the efficiency of goat meat production in the Brazilian semiarid. Moreover, in times of feed scarcity, farmers may use higher feed restriction levels to keep animals, since for most of the parameters evaluated, there were no differences between the restriction levels.

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