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This study aimed to evaluate the effect of calcium lignosulfonate associated with whole cottonseed in high-concentrate diets for sheep. Eight Dorper crossbred sheep with an average live weight of 42.5 ± 1.70 kg were assigned to two 4 × 4 Latin squares. The following experimental diets were evaluated: control diet (without calcium lignosulfonate) and diets with inclusion of 50, 100, and 150 g of calcium lignosulfonate/kg fresh matter. Diets were composed of soybean meal, ground corn, and whole cottonseed. Feed intake, digestibility, metabolic characteristics, and feeding behavior were evaluated. The intake of nutritional components did not show significant differences as a function of the lignosulfonate levels in the diet; however, the increase in calcium lignosulfonate levels linearly decreased the dry matter digestibility. Rumen ammonia nitrogen concentrations decreased linearly as the lignosulfonate levels in the diets were increased. There was no effect of lignosulfonate levels on blood parameters or feeding behavior of the animals. The use of lignosulfonate associated with cottonseed decreases the digestibility of dry matter and the concentration of rumen ammonia nitrogen, but does not change the intake of nutritional components, the blood parameters, or the feeding behavior of sheep.

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Objetivou-se estudar a viabilização dos indicadores internos, celulose (CELi) e lignina (LIGi) indigestíveis, obtidos pelas técnicas in situ e in vivo, para predizer a digestibilidade de nutrientes em equinos. Foram utilizados quatro cavalos castrados, por meio de delineamento em blocos ao acaso. Os tratamentos consistiram de metodologias de avaliação de digestibilidade, como a coleta total de fezes (CT) e o uso de indicadores internos, CELi e LIGi, obtidos pelas técnicas in situ (IS) na cavidade ruminal de bovinos e in vivo (IV) nos equinos, por meio da técnica do saco de náilon móvel (TSNM), totalizando cinco tratamentos. A ingestão diária de MS foi de 2,0 por cento do peso vivo de feno de coast-cross. A CELi-IV promoveu a melhor taxa de recuperação do indicador, igualando-se à CT, em 100,31 por cento, enquanto a LIGi resultou nas piores taxas, na média 76,45 por cento, para ambas as técnicas (P<0,05). As estimativas dos coeficientes de digestibilidade dos nutrientes foram adequadamente preditas pela CELi, obtidos IS e IV em que os valores observados foram de 46,41, 48,16, 46,90, 47,92 e 45,51 por cento para MS, MO, PB, FDN e EB, respectivamente. Concluiu-se que a CELi pode ser obtida in vivo por meio da TSNM em equinos, para predizer a digestibilidade de nutrientes...

The objective of this paper was to study the use of the internal indigestible cellulose (CELi) and lignin (LIGi) markers, obtained in situ or in vivo, to predict the apparent digestibility of nutrients in horses. Four castrated horses were utilized in a randomized blocks experimental design. Treatments consisted of different digestibility determination methodologies: total feces collection (TC) and use of CELi and LIGi internal markers obtained by the in situ (IS) incubation in bovine rumen and in vivo (IV) by the mobile nylon bag technique (MNBT) with horses, resulting in five treatments. The diet consisted exclusively of coast-cross hay and the average daily dry matter intake corresponded to 2.0 percent of the BW of the horses. The CELi-IV resulted in the best marker recuperation rate (100.31 percent), being similar to the control method; while the LIGi resulted in low recuperation rates (76.45 percent) for both techniques (P<0.05). The nutrients' digestibility coefficients were effectively predicted by CELi, obtained in situ or in vivo, with average values of 46.41, 48.16, 46.90, 47.92 and 45.51 percent for DM, organic matter, crude protein, neutral detergent fiber and crude energy, respectively. It can be concluded that CELi may be obtained in vivo by MNBT in horses to predict the nutrients' digestibility coefficients...

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Objetivou-se estudar a viabilização dos indicadores internos, celulose (CELi) e lignina (LIGi) indigestíveis, obtidos pelas técnicas in situ e in vivo, para predizer a digestibilidade de nutrientes em equinos. Foram utilizados quatro cavalos castrados, por meio de delineamento em blocos ao acaso. Os tratamentos consistiram de metodologias de avaliação de digestibilidade, como a coleta total de fezes (CT) e o uso de indicadores internos, CELi e LIGi, obtidos pelas técnicas in situ (IS) na cavidade ruminal de bovinos e in vivo (IV) nos equinos, por meio da técnica do saco de náilon móvel (TSNM), totalizando cinco tratamentos. A ingestão diária de MS foi de 2,0 por cento do peso vivo de feno de coast-cross. A CELi-IV promoveu a melhor taxa de recuperação do indicador, igualando-se à CT, em 100,31 por cento, enquanto a LIGi resultou nas piores taxas, na média 76,45 por cento, para ambas as técnicas (P<0,05). As estimativas dos coeficientes de digestibilidade dos nutrientes foram adequadamente preditas pela CELi, obtidos IS e IV em que os valores observados foram de 46,41, 48,16, 46,90, 47,92 e 45,51 por cento para MS, MO, PB, FDN e EB, respectivamente. Concluiu-se que a CELi pode ser obtida in vivo por meio da TSNM em equinos, para predizer a digestibilidade de nutrientes.(AU)

The objective of this paper was to study the use of the internal indigestible cellulose (CELi) and lignin (LIGi) markers, obtained in situ or in vivo, to predict the apparent digestibility of nutrients in horses. Four castrated horses were utilized in a randomized blocks experimental design. Treatments consisted of different digestibility determination methodologies: total feces collection (TC) and use of CELi and LIGi internal markers obtained by the in situ (IS) incubation in bovine rumen and in vivo (IV) by the mobile nylon bag technique (MNBT) with horses, resulting in five treatments. The diet consisted exclusively of coast-cross hay and the average daily dry matter intake corresponded to 2.0 percent of the BW of the horses. The CELi-IV resulted in the best marker recuperation rate (100.31 percent), being similar to the control method; while the LIGi resulted in low recuperation rates (76.45 percent) for both techniques (P<0.05). The nutrients' digestibility coefficients were effectively predicted by CELi, obtained in situ or in vivo, with average values of 46.41, 48.16, 46.90, 47.92 and 45.51 percent for DM, organic matter, crude protein, neutral detergent fiber and crude energy, respectively. It can be concluded that CELi may be obtained in vivo by MNBT in horses to predict the nutrients' digestibility coefficients.(AU)

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Two experiments using the Cornell Net Carbohydrate and Protein System were conducted to characterize the carbohydrate and protein fractions and corresponding rates of digestion of 15 tropical pasture grasses and to evaluate their ability to support milk production by dual-purpose cows. In the first experiment, ranges in carbohydrate and protein fractions of 15 grasses at 35 to 42 d of regrowth were: neutral detergent fiber (NDF) 63.5 to 74.9% of DM; permanganate lignin 4.7 to 7.8% of NDF; CP 5.5 to 11.9% of DM; and soluble protein 15.1 to 44.1% of crude protein (CP). The ranges of rates of digestion expressed as percent per hour were neutral detergent solubles (7.5 to 27.4); NDF (3.8 to 8.4); and neutral detergent insoluble protein (2.9 to 9.5). Predictions of the amount of milk that could be produced based on the amount of metabolizable energy supplied by the diet decreased 35% when NDF increased from 60 to 80%, and increased 88% when the rate of digestion of NDF increased from 3 to 6%/h. The milk production that could be sustained based on metabolizable protein in the diet doubled as CP increased from 4 to 12%. In the second experiment, nitrogen fertilization reduced NDF 7.3% and increased CP 84% without changing protein solubility, resulting in increased rumen nitrogen and metabolizable protein balances. With all forages, the Cornell Net Carbohydrate and Protein System predicted that availability of metabolizable protein would limit milk production. Predicted microbial growth was limited by ruminally available protein rather than by available carbohydrate.

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Voluntary intake and nutritive value of diets selected by goats grazing a shrubland at Marin county, N.L., Mexico were determined. Four esophageally cannulated Spanish female goats (average BW 35 kg), were used to collect extrusa samples monthly throughout 1 yr (June 1987 to May 1988). Organic matter intake (OMI) was estimated by total fecal collections from four castrated Spanish male goats (average BW 42 kg). Diets selected by goats were high in CP throughout the year (means = 18.9%). Available CP represented only about half the total CP. The ADF content of extrusa samples differed (P less than .05) among months, with high ADF values during winter months. Dietary lignin followed a similar pattern during the year. Goats consumed forage with sufficient amounts of Ca, Na, K, Mg, Cu, ZN, Mn, and Fe to meet requirements. The OMI of goats was different (P less than .05) among sampling periods. On the average, estimated OMI (means = 878.7 g/d) compared well with results of other studies in the area. Amounts of DE consumed by goats (1.1 Mcal DE/d) were not sufficient to meet requirements for maintenance plus low activity. High levels of browse in the diets presumably were responsible for low in vitro OM digestibility (means = 34.1%) throughout the year. Thus, productivity of range goats in these areas should be improved by supplementing with protein and energy.

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Nutritive composition of diets and forage intake of goats utilizing pastures of cleared, two levels of thinned (25% and 55% canopy cover) and undisturbed (control) tropical woodland were compared on a seasonal basis. Esophageally fistulated goats were used to collect dietary samples for chemical analysis. Total fecal collections were used to estimate organic matter intake (OMI) and digestible energy intake (DEI). Forage availability during the wet season was more than threefold higher (P less than .1) on treated than on control pastures. Although available forage was similar (P greater than .1) for all treatments by the middle of the dry season, available forage on the control pastures was limited mostly to dry tree leaves. Goats selected diets 4% higher (P less than .1) in neutral detergent fiber on the control pastures than on the treated pastures; otherwise, diets selected by the goats on the various pastures were similar in terms of crude protein, lignin and in vitro organic matter digestibility. However, OMI and DEI were 23 and 31% higher (P less than .1), respectively, on the treated pastures than on the control pastures. There were no differences among the cleared and thinned treatments. Excessively wet conditions during the rainy season adversely affected goat performance. High populations of biting insects and wet field conditions reduced foraging time and diet selection. The generally higher levels of available forage on the cleared and thinned pastures did not result in the goats' selecting diets higher in nutritive value on the treated pastures than on the control pastures. Instead, the increased forage availability for the treated pastures allowed the goats to attain higher intake of forage.

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