Effect of slow-release urea on intake, ingestive behavior, digestibility, nitrogen metabolism, microbial protein production, blood and ruminal parameters of sheep.

We conducted two experiments. The first aimed to obtain and characterize microparticles of slow-release urea (SRU) using calcium alginate as the encapsulating agent. The second experiment evaluated their inclusion in sheep diets. In the first experiment, four treatments from a completely randomized design were employed to develop an SRU through the ionic gelification technique testing two drying methods (oven and lyophilizer) and addition or no of sulfur (S): SRU oven-dried with sulfur (MUSO) and without sulfur (MUO), SRU freeze-dried/lyophilized with (MUSL), and without sulfur (MUL). MUO exhibited better yield and encapsulation efficiency among these formulations than the others. Therefore, the second experiment was conducted to compare free urea (U) as control and three proportions (1%, 1.5%, and 2% of total dry matter) of MUO in the diet of sheep. Twenty-four non-castrated male Santa Ines lambs, with an average body weight of 22 ± 3.0 kg, were used and distributed in a completely randomized design with four treatments and six replications. The inclusion of 1% alginate-encapsulated urea (MUO1%) resulted in higher dry matter (DM) intake than free urea (p ≤ 0.05). MUO2% inclusion promoted higher NDF digestibility than U and MUO1%. MUO1% showed higher DM than MUO2% and higher NFC digestibility than U and MUO2% (p ≤ 0.05). Sheep fed MUO1.5% and MUO2% exhibited similar nutrient intake and digestibility. Sheep receiving MUO1% had higher N-intake, N-urinary, N-excretion total, N-digested, and N-retained compared to U. Sheep fed MUO1% showed greater N-retained (as % ingested and digested), microbial protein production, and efficiency when compared to other treatments (p ≤ 0.05). MUO2% addition (SRU) promoted the lowest microbial protein production and efficiency in sheep. MUO dietary inclusion increased feeding time and reduced idleness time compared to U, regardless of the MUO level (p ≤ 0.05). Adding MUO1% improved the intake efficiency of DM and NDF and resulted in more feed boli than the other MUO levels (p ≤ 0.05). Sheep receiving U had (4 h after fending) higher NH3-N, pH, and blood urea nitrogen (BUN) and lower TGL serum compared to sheep fed MUO (p ≤ 0.05), without significant difference among MUO levels (p > 0.05), except NH3-N was higher in MUO1.5% and MUO2% compared to MUO1.0%. The external ionic gelation technique proved suitable for urea microencapsulation in calcium alginate (3%), demonstrating high quality, efficiency, and yield. MUO represents a promising slow-release urea for ruminants and is recommended for sheep diets at an inclusion level of 1.0%. This inclusion level improves intake efficiency and nutrient digestibility, increases rumen nitrogen retention, and reduces BUN without compromising sheep health.

Polymorphism of the beta-casein gene and adaptability of Sindhi cows to semiarid conditions.

This study aimed to investigate the effect of beta-casein genotypes (A1A2 and A2A2) in three different thermal comfort conditions on the adaptability of Sindhi cows and as a tool for selecting thermotolerant cattle. Twelve Sindhi cows were used in a completely randomized design in a 2 × 3 factorial arrangement, with six replicates, with two genotypes, and three thermal comfort conditions. The climatic variables were recorded, while black globe temperature, humidity index, and radiant heat load were calculated. We measured respiratory rate, surface temperature, and rectal temperature while the heat tolerance coefficient was calculated. Genotype had no significant effect (p > 0.05) on any of the parameters measured. However, there was a thermal comfort condition effect (p < 0.05) on rectal temperature, surface temperature, and thermal gradients. The respiratory rate and heat tolerance coefficient were not significantly affected (p > 0.05). Therefore, although the results indicate substantial adaptability of Sindhi cows under any thermal conditions, the tested genotypes should not be used as a tool for selecting thermotolerant Sindhi cows.

Fatty acid, chemical, and tissue composition of meat comparing Santa Inês breed sheep and Boer crossbreed goats submitted to different supplementation strategies.

To compare the fatty acid (FA) composition, and chemical and tissue composition of meat, 24 uncastrated males, 12 sheep of the Santa Inês breed, and 12 crossbred goats (F1 Boer × undefined breed) with the weight of 24.3 ± 2.38 kg. The animals were distributed in a randomized block design and treatments were arranged in a 2 × 2 factorial design, two small ruminant species/breed (Boer crossbreed goat × Santa Inês breed sheep), and two supplementation strategies (energy × protein energy). There was not an interaction between the small ruminant species and the supplementation on average daily gain, tissue composition, chemical composition, or FA profile of the longissimus lumborum muscle. Sheep presented greater weight and yield of fat in the subcutaneous, intermuscular, and total depots than goats, which results in better finishing of the sheep for slaughter. Goat meat presented a lower lipid concentration than sheep meat. The protein-energy supplementation increased oleic acid, ΣUFA, ΣMUFA, hypocholesterolemic/ Hypercholesterolemic index, and enzymatic activity Δ9-desaturase C18 and decreased SFA capric acid in the muscle when compared with energetic supplementation. In Caatinga biome conditions, Boer crossbreed goats meat has a lower concentration of lipids and a healthier FA composition compared with Santa Inês breed sheep because it has a lower SFA and greater PUFA content, which are sources of n-3 and n-6, which may contribute to the reduction of blood cholesterol (LDL). In addition, protein-energy supplementation also improved the quality of animal fat compared with supplementation only with the energetic concentrate, regardless of species.

Efeito da inclusão de fontes lipídicas na dieta de cabras em lactação sobre os parâmetros sanguíneos / Effect of fat source inclusion in the diet of lactating goats

Conduziu-se o estudo do perfil metabólico, com o objetivo de avaliar o estado nutricional ou possíveis distúrbios metabólicos que podem comprometer a saúde e, consequentemente, o desempenho do rebanho. No presente trabalho foi avaliado o perfil metabólico de cabras em lactação, submetidas a dietas com diferentes fontes de lipídios. Foram utilizadas 16 cabras da raça Saanen com peso vivo médio de 35 Kg e produção média diária de 1,2 kg de leite, distribuídas em quadrado latino com três repetições. Os tratamentos experimentais consistiram nas seguintes dietas: sem suplementação lipidica (TC); semente de faveleira (SF); torta de faveleira (TF) e caroço de algodão (CA). O experimento foi desenvolvido em quatro períodos experimentais de 14 dias, sendo 10 dias de adaptação à dieta e quatro dias de coleta de dados. No último dia de cada período foram coletadas amostras de sangue. A inclusão de semente de oleaginosa na dieta de cabras em lactação diminuiu o consumo de matéria seca por unidade metabólica (CMSU) e consumo de proteína bruta por unidade metabólica (CPBU). Dentre os quatro tratamentos não se observou diferença significativa no que se refere à concentração sérica de uréia, creatinina, GGT (gama glutamiltransferase), cálcio, fósforo, magnésio e glicose. Os níveis séricos de albumina dos animais que receberam TF foram maiores (P<0,05) do que os animais do grupo controle. Este trabalho sugere que as fontes de oleaginosas podem ser utilizadas na suplementação lipídica de cabras Saanen em lactação, entretanto animais alimentados com TF apresentaram um perfil metabólico mais saudável em função da suplementação lipídica.

The study of the metabolic profile has as objective to evaluate the nutritional status or possible metabolic disturbances that can damage the health and consequently the herd performance. In this work, the metabolic profile of lactating goats was evaluated, submitted to diets with different fat sources. 12 Saanen goats with BW of 35 kg and daily milk production of 1,2 kg were used, distributed into a Latin square with three repetitions. The diet comprised, without fat supplementation, TC (control) and with fat supplementation: SF (favelone seed); TF (favelone cake) and CA (cotton seed).The experiment was developed in four experimental periods of 14 days, with 10 days of adaptation to diets and four days for samples collection. In the last day of each period were collected blood samples. The inclusion of oleaginous seed into the lactating goats' diet decreased the dry matter consumption for metabolic unit (CMU) and consumption of crude protein for metabolic unit (CPMU). No significant differences in serum urea, creatinine, GGT (gamma glutamyltransferase), calcium, phosphorus, magnesium or glucose values were noticed in any of the four treatments. The serum levels of albumin in the animals that received TF were higher (P<0.05) than the animals of the control group. This work suggests that the oleaginous sources can be used as fat supplementation of lactating Saanen goats; however, animals fed the TF showed a healthier metabolic profile due to the fat supplement.

Características da carcaça de ovinos Santa Inês terminados em pastejo e submetidos a diferentes níveis de suplementação / Carcass characteristics of Santa Inês sheep finished in grazing and submitted to different levels of supplementation

Objetivou-se, com esse trabalho, avaliar as características da carcaça de cordeiros Santa Inês, mantidos em pastagem nativa e submetidos a diferentes níveis de suplementação na dieta (1,5 por cento, 1,0 por cento e 0,0 por cento do peso vivo). Foram utilizados 24 animais, machos castrados, com peso vivo (PV) médio inicial de 15 kg ± 1,44 e idade média de 150 dias. O concentrado foi constituído à base de milho moído, farelo de soja e sal mineral. O delineamento utilizado foi inteiramente casualizado, com três tratamentos e oito repetições. A utilização da suplementação possibilitou a obtenção de cordeiros com características mais desejáveis da carcaça, como: melhor rendimento, maior área de olho de lombo, menor perda de peso no resfriamento e maior peso dos cortes comerciais. Em termos de análise econômica, pode-se concluir que, se o objetivo for obter carcaças mais leves com peso em torno de 7 kg e com nível mínimo de gordura não há necessidade de suplementação com concentrado, mas, se o objetivo for obter carcaças pesando de 10 a 12 kg e com melhor nível de acabamento recomenda-se suplementação com 1,0 a 1,5 por cento do peso vivo com concentrado.

The aim of this study was to evaluate carcass characteristics of Santa Inês lambs, maintained in native pasture and submitted to different supplementation levels in the diet (1,5 percent, 1,0 percent e 0,0 percent do LW). Twenty-four castrated sheep with 15 ±1,44 kg of mean live weight (LW) were used and average age of 150 days. The concentrate was constituted of cracked corn, soybean meal and mineral salt. A completely randomized design with three treatment and eight replicates was used. The use of the supplementation makes possible to get lambs with desirable characteristics of the carcass, such as: better yield, increase rib eye area, less lose of weight in the cooling, and greater weight of retail cuts. According to the economical analysis it may be concluded that, if the aim is to get lighter carcasses with weight around 7 kg and with minimum level of fat there is not any necessity of supplementation with concentrate, but, if the aim is to get the carcasses weighing from 10 to 12 kg and with better level of finishing, it is recommended supplementation with 1,0 to 1,5 percent of the live weight with concentrate.

Parâmetros fisiológicos e desempenho de ovinos Santa Inês submetidos a diferentes tipos de sombreamento e a suplementação em pastejo / Physiologic behavior and performance of lambs Santa Inês breed submitted to different types of environmental and supplementation in grazing

Objetivou-se com este trabalho avaliar o efeito da disponibilidade de sombra e da suplementação com concentrado sobre o comportamento fisiológico e o desempenho de cordeiros Santa Inês em pastejo no semi-árido paraibano. Foram utilizados 27 ovinos machos da raça Santa Inês, com peso vivo médio de 21,5 kg e 120 dias idade. Os animais foram distribuídos aleatoriamente em três ambientes [sem sombra (SS), sombra natural (SN) e sombra artificial (SA)] e alimentados com três níveis de suplementação concentrada (0, 1,0 e 1,5 por centoPV). A análise de variância revelou efeito significativo do turno da tarde em relação ao da manhã sobre a temperatura retal (TR). Contudo, não se verificou efeito significativo dos fatores ambiente e dieta sobre a TR. A freqüência respiratória foi maior no turno tarde do que no da manhã nos ambientes de SS (35,28 e 61,64 mov/mim) e SA (30,28 e 51,76 mov/mim). A dieta influenciou a ingestão de matéria seca (IMS) no ambiente SS. A temperatura superficial foi mais elevada no turno da tarde do que pela manhã, independente dos fatores estudados. Os animais que receberam suplementação apresentaram um melhor desempenho em relação aos não suplementados. Concluiu-se com esta pesquisa que o uso de sombreamento nas pastagens melhora os índices de conforto térmico do ambiente, e que o desempenho de cordeiros da raça Santa Inês, em pastagem nativa enriquecida com capim buffel pode ser melhorado com a utilização de concentrado.

The objective of this work was to evaluate the effect of the shadow and food supplementation on the physiologic behavior and performance of Santa Inês lambs under rangeland conditions in the semi-arid region of Paraíba. Twenty-seven male lambs were used, with an average body weight of 21.5 kg and 120 days of age. They were randomly distributed in three environments [without shade (WS), natural shade (NS) and artificial shade (AS)] and fed growing three levels of concentrate supplement (0, 1.0 and 1.5 percent of live body weight). The analysis of variance revealed significant effect of period (morning x afternoon) on rectal temperature. However, no significant effect was observed for the environment and diet factors. Breathing frequency was higher in the afternoon than in the morning in the WS (35.28 and 61.64 mov/minute) and AS (30.28 and 51.76 mov/minute) environments. The diet influenced DM ingestion in SS environment. Skin temperature was higher in afternoon than in the morning, independent of the studied factors. The animals supplemented with concentrate mixtures had a performance better than the control ones. It was concluded that shading improved the indexes of thermal comfort and animal physiology and production parameters. Santa Inês breed showed high adaptability to the adverse conditions of the semi- arid region of Paraíba. The performance of Santa Inês lambs under a buffel enriched native rangeland, can be improved by supplementation with concentrate.

Efeito da restrição alimentar sobre algumas características de carcaça de cabritos F1 Boer X Saanen / Effect of feed restriction on some carcass traits of F1-Boer X Saanen goats

Objetivou-se com este trabalho avaliar o efeito da restrição alimentar nas características de carcaça de cabritos F1 Boer x Saanen. Foram utilizados 21 cabritos, pesando 15 kg de PV, distribuídos em três tratamentos (0, 30 e 60 por cento de restrição). O consumo dos animais do tratamento 0 por cento de restrição determinavam o consumo dos animais dos tratamentos 30 e 60 por cento de restrição. Quando os animais do nível de restrição 0 por cento atingiam 25 kg, estes juntamente com seus pares foram submetidos a jejum de sólido de 24 h e de líquido de 16 h. O abate ocorreu mediante descarga elétrica, seguido de sangria e retirada dos órgãos. Os ganhos de peso foram de 211,03, 126,15 e 11,71g/dia; a eficiência alimentar de 0,20, 0,18 e de 0,03; os pesos de abate de 25,44, 20,91 e 15,82kg para os tratamentos 0, 30 e 60 por cento de restrição, respectivamente. O rendimento de carcaça quente, de carcaça fria e biológico não foram influenciados pela restrição alimentar. Somente a proporção da paleta e a do lombo foram influenciados pela restrição alimentar, com aumento linear do rendimento da paleta e decréscimo linear do rendimento do lombo. Houve efeito da restrição na redução do rendimento de gordura e aumento da proporção de osso. A restrição alimentar em níveis moderados, permitiu a obtenção de carcaças de boa qualidade, com bom rendimento, elevada proporção de músculo e baixa participação de gordura e, dependendo da relação custo:benefício, pode tornar-se boa alternativa para o produtor.

To evaluate the effect of different levels of feed restriction on carcass traits, twenty-one F1-Boer x Saanen goats weighting 15 kg LW were allocated to one of the three treatments (0, 30 and 60 percent restriction). The feed intake for the 0 percent restriction treatment animals determined the intake for the animals in the 30 and 60 percent restriction treatment. When animals from 0 percent of feed restriction reached 25 kg of LW, they and their pair-feeding were submitted to a feed and water fasting during 24 h and 16 h, respectively. After fasting, animals were slaughtered by electric discharged. In addition, bleeding and organs removing were performed. The weight gain (g/day) were 211,03, 126,15 and 11,71; the feed efficiency was 0,20, 0,18 and 0,03; the slaughtering weight (kg) were 25,44, 20,91 and 15,82 for 0, 30 e 60 percent restriction treatment, respectively. Warn carcass, cold carcass and biological yields were no affected by feed restriction. Only, shoulder and loin proportions were affected by feed restriction with a linear increase of shoulder yield and a linear decrease of loin yield. Feed restriction reduced fat yield and increased bone proportion. Moderate levels of feed restriction permitted to produce goat carcasses with good quality and yield, as well as high muscle proportion and low fat content. Depends on the cost: benefit ratio feed restriction should be consider an adequate alternative for meat goat producer.