Nutritional strategies, performance, digestibility, and carcass traits of Santa Ines and Rabo Largo breeds in a tropical climate.

The aim of this study was to compare the performance, intake, digestibility, ruminal parameters, carcass traits, and the yield of commercial cuts of Santa Ines (SI) and Rabo Largo (RL) breeds fed diets with high or low roughage-to-concentrate ratio (R:C) under a tropical climate. Twenty lambs from each breed were individually housed in covered pens and fed the experimental diets for 58 days. The diets were formulated to meet the growth requirements of lambs with a roughage-to-concentrate ratio of 70:30 and 30:70. Significant interactions of breed × diet for nutrient intake were observed (P < 0.05), with SI lambs fed low R:C diet showing higher intake of dry matter, organic matter, crude protein, and total carbohydrates compared to RL lambs fed the same diet. SI lambs fed high R:C diet had higher intake of neutral detergent fiber than RL lambs (P < 0.05). SI lambs displayed better average daily gain and feed efficiency, regardless of diet (P < 0.05). Carcass traits and gastrointestinal components were influenced by breed and diet (P < 0.05). SI lambs fed low R:C diet showed higher subcutaneous fat thickness and better carcass finishing compared to RL lambs (P < 0.05). SI breed lambs exhibited better growth performance, carcass traits, and gastrointestinal characteristics, even when fed diets with a high roughage-to-concentrate ratio.

Effect of concentrate supplement to ewes on nutritive value of ingested Caatinga native forage nutritive value as affected by season.

The objective of this study was to identify by microhistological technique the reference chemical components for use as indicators of the nutritive value of Caatinga plants forage grazed by sheep throughout the year. A flock of twenty mixed-race meat ewes, multiparous, in production, with an average 34.84 ± 1.75 kg live weight and 36 months of age was assigned to supplement treatment of 0, 200, 350, and 500 g concentrate/head/day for 3 years. The experiment was designed as a randomized complete design with repeated measures over time. Supplementation with concentrate did not influence chemical composition of selected forage. In contrast, season heavily influenced diet chemical composition. Canopy stratum, season, and plant botanical family of selected species affected forage chemical composition selected by ewes. The ewes selected forage with greater nutritive value during the rainy season. Based on principal component analysis of the nutritive value of the primary forage species selected, ewes preferentially grazed plants contained greater neutral detergent fiber, acid detergent fiber, crude protein (CP), C fraction of nitrogenous compounds, and carbohydrate fractions A + B1 and C compared to the average native Caatinga herbage. Rangeland botanical composition and ewe diet varied during the year, affecting forage nutrients on offer, with the best diet selected during the rainy season because of the presence of dicotyledonous herbaceous species rich in CP as well as soluble carbohydrates and nitrogenous compounds. Concentrate supplement strategies for ewes on rangelands, such as Caatinga, should be determined by herbaceous species nutritive value during the rainy season and deep-rooted perennial dicotyledons during the dry season. These include the need to monitor ewe selection of forage species and their nutritive value, which is effectively accomplished with fecal microhistological techniques.

Influence of nutrient restriction on finishing Morada Nova lambs.

Our objective was to evaluate the effect of 15% crude protein (CP) and total digestible nutrient (TDN) restriction vis-á-vis that recommended by NRC (2007) on feed intake, digestibility, and average daily gain (ADG) of confined Morada Nova lambs. Twenty lambs with 18.8 ± 2.8 kg liveweight were assigned to a randomized 2 × 2 factorial experiment with either early- or late-maturity feed formulation according to "Nutrient Requirements of Small Ruminants" with or without 15% CP and TDN restriction. The early-maturity diet, independent of restriction, resulted in greater dry matter and organic matter intake and increased rumination efficiency and feed conversion. Early-maturity diets also had the greatest nutrient digestibility as well as ADG and total gains. With late-maturity diets, independent of restriction, there were greater CP and TDN digestibilities as well as neutral detergent fiber (NDF) feed efficiency. However, when 15% of nutrients were restricted for late-maturity lamb diets, there was greater NDF intake and greater ether extract digestibility. Unrestricted early-maturity lamb diets was the better diet for confined Morada Nova lambs. Attention should be given to minimum effective NDF consumed and physically effective for this diet formulation. The use of late-maturity diets as recommended by NRC (2007) allows for 15% restriction of CP and TDN in Morada Nova lambs without negative effects on performance. This restriction should be tested in other tropical breeds to determine wider application.

Intake, Nutrient Apparent Digestibility, and Ruminal Constituents of Crossbred Dorper × Santa Inês Sheep Fed Diets with Babassu Mesocarp Flour.

The aim of this study was to evaluate the effect on intake, apparent digestibility, and ruminal constituents of sheep in response to the addition of increasing levels of babassu mesocarp flour (BMF) to the diet. Twenty crossbred sheep (29.17 ± 2.23 kg) were used in a randomized complete block design. Lambs were confined for 21 days, with 16 days for diet adaptation and 5 days for data collection, in which they were fed an isonitrogenous diet (16.5 ± 0.2 CP, DM basis) containing 70% of concentrate and 30% (DM basis) of Tifton 85 hay. Increasing levels of BMF were 0, 10, 20, and 30% (DM basis). There was a quadratic effect (P < 0.05) on the DM intake, nutrients intake, and digestibility of CP and NFC. The digestibility of DM, OM, TC, and NDF decreased linearly, while EE digestibility increased linearly with increasing levels of BMF. The high NDF content presented in the chemical composition of the babassu mesocarp flour ranked the same as fibrous food, which can limit the inclusion in the diet of high production animals. So, babassu mesocarp flour is an alternative for energy source in lambs feed and can be added at levels up to 10%.

Efeito do tamanho de partícula sobre a degradação ruminal do feno do restolho da cultura do girassol / Effect of the particle size on ruminal degradation of sunflower crop stubble hay

Objetivou-se avaliar os teores de matéria seca, proteina bruta e fibra em detergente neutro e a degradabilidade da matéria seca (MS), proteína bruta (PB) e fibra em detergente neutro (FDN) do feno do restolho da cultura do girassol in situ em diferentes tamanhos de partículas (2 e 5 cm), utilizando-se um bovino canulado, com amostras em sacos de náilon, incubadas nos tempos 6, 24 e 72 h. O feno de restolho da cultura do girassol triturado em partículas de 2 mm resultou em maior degradação por microrganismos da flora ruminal em relação à trituração a 5 mm. Verificou-se que as partículas de maior tamanho apresentaram valores equivalentes para degradação da MS e FDN as 24 e 72 horas. Os parâmetros da degradação da FDN do feno do restolho da cultura do girassol indicam ser um volumoso com grande potencial para utilização na dieta de ruminantes. O feno do restolho da cultura do girassol, enquanto considerado um alimento volumoso, apresenta degradabilidade in situ da MS e FDN compatível com esta classe de alimentos, podendo ser considerado uma boa fonte de inclusão em dietas para ruminantes. Também se deve considerar o elevado teor de PB associado à degradação ruminal deste constituinte, favorecendo à atividade fermentativa pela população microbiana do ambiente ruminal.

It was aimed to evaluate the degradability of dry matter (DM), crude protein (CP) and neutral detergent fiber (NDF) of the stubble sunflower crop hay in situ in different particle sizes, using a cannulated bovine, with samples in nylon bags incubated in the 6, 24 and 72 h. The stubble sunflower crop hay grinded in 2 mm particles sized resulted in greater degradation by the rumen microorganisms compared to samples grinded in 5 mm. It was found that the larger particles had equivalent values for DM and NDF degradation at 24 and 72 hours. The parameters of NDF degradation of the stubble sunflower crop hay to indicate be a roughage with great potential for use in the ruminant diet. The stubble sunflower crop hay, while considered a roughage food, presents in situ DM and NDF compatible with this kind of food, and it can be considered a good source of inclusion in diets for ruminants. Also to consider the higher protein value associated with ruminal degradation of this constituent, favoring the fermentation activity by the microbial population in the rumen.

Desempenho produtivo de cabritos alimentados com glicerina bruta / Productive performance of goat kids fed of crude glycerin

Avaliou-se o desempenho produtivo de cabritos mestiços terminados em confinamento, alimentados com dietas contendo glicerina bruta (0, 4, 8 e 12% na MS). Vinte cabritos mestiços foram utilizados em blocos completos, casualizados com quatro tratamentos e cinco repetições, para determinação do ganho médio diário (GMD), consumo de matéria seca (CMS) e nutrientes (PB, FDN, EE) e comportamento ingestivo. Para o ensaio de digestibilidade, foram utilizados quatro caprinos alocados em delineamento em quadrado latino, para determinação da digestibilidade da MS e nutrientes (PB, FDN, EE). A adição de glicerina bruta não interferiu (P>0,05) no GMD e no CMS e demais nutrientes. O tempo de ingestão aumentou com o incremento de glicerina bruta nas dietas. Não houve diferença significativa (P>0,05) dos tratamentos sobre o tempo gasto na ruminação e digestibilidade da MS, PB e FDN, contudo, houve efeito quadrático para a digestibilidade do EE. Recomenda-se a inclusão em até 12% de glicerina bruta para cabritos em terminação, em situações de oscilação do preço do milho, sem alteração nos parâmetros produtivos avaliados.

This study was conducted to evaluate the productive performance of crossbred goats finished in feedlots fed diets containing increasing levels of crude glycerin (0, 4, 8 and 12%, DM basis). Twenty crossbred goat kids were used in a randomized complete block design with 4 treatments and 5 replications to determine average daily gain (ADG), dry matter intake (DMI) and nutrients (CP, NDF, EE) and ingestive behavior. For digestibility trial, four castrated male goats were used in a Latin Square Design to determine the DM and nutrients digestibility. Crude glycerin did not affect (P>0.05) the ADG, DMI and nutrients intake. Eating time increased linearly (P<0.05) with crude glycerin addition. Rumination time and dry matter and nutrients digestibility were unaffected by crude glycerin addition. However was a quadratic effect (P<0.05) to EE digestibility. It is recommended adding up to 12% crude glycerin to finishing kids, in situations of high price of corn, without changes in production parameters evaluated.

Valor nutritivo do feno de folíolos de pindoba de babaçu submetido a tratamentos alcalinos / Nutritive value of leaflets pindoba babassu hay subjected to alkaline treatments

Avaliou-se o efeito de tratamentos alcalinos por amonização com ureia a 2, 4 e 6% e por NaOH ou Ca(OH)2 a 1, 2 e 3% sobre o valor nutritivo do feno de folíolos de pindoba de babaçu quanto à composição e degradabilidade ruminal in situ nos tempos 6, 24 e 72h. Houve redução (P<0,05) nos teores de fibra em detergente neutro e em detergente ácido corrigidas para cinza e proteína (FDNcp e FDAcp) e nas frações hemicelulose e lignina quando dos tratamentos alcalinos, verificando-se ainda aumento (P<0,05) nos teores de proteína bruta (PB) e redução no N insolúvel quando da amonização. A degradação potencial (DP) da matéria seca (MS) e FDN do feno mostrou-se baixa, embora a amonização com 4% de ureia tenha elevado a degradação potencial e efetiva da PB, o que se atribui à intensa lignificação da parede celular, com limitação à utilização como volumoso em dietas para ruminantes. A amonização e o tratamento com 3% de Ca(OH)2 melhoram a degradação da MS e FDN, com destaque para a amonização com 4% de ureia, no entanto, os valores obtidos, 35,9 e 27,04%, respectivamente, são considerados baixos.

It was evaluated the effect of alkaline treatments by ammoniation with urea at 2, 4 and 6% NaOH or Ca(OH)2 and at 1, 2 and 3% on the nutritional value of the hay leaflets pindoba babassu chemical composition and degradability in situ at times 6, 24 and 72 hours. There was a reduction (P<0.05) in the contents of fiber (NDFap and ADFap) and in the hemicellulose and lignin fractions when alkaline treatments, verifying also increased (P<0.05) in contents of crude protein (CP) and reduction in insoluble N when ammoniation. The degradation potential (DP) of DM and NDF of hay in general were low, although the ammoniation with 4% urea (35.9%) has high potential degradation and effective of CP, which is attributed to intense lignification of the cell wall, with limitation to the use with forage for ruminants. The alkaline treatments contributed to the improvement the chemical composition of leaflets pindobababassu hay, by reducing the content of hemicellulose, lignin and insoluble nitrogen and increase CP. The ammoniation and treatment with 3% Ca(OH)2 improves the potential degradation of DM and NDF of hay leaflets pindobababassu, highlighting the level of 4% urea, based on MS, although the values obtained with this treatment, 35.9 and 27.0%, are considered low.