Evaluation of internal markers in digestibility estimation for sheep and goats.

The objective of this study was to compare the indirect methods of obtaining digestibility with the direct method of total fecal collection to estimate the apparent digestibility of nutrients in sheep and goats supplemented with non-protein nitrogen. Five goats and five sheep with no defined racial pattern were used, distributed in two 5 × 5 Latin squares, with split plots, considering the diets as plots and the apparent digestibility determination methodologies as subplots. The diets were composed of buffelgrass hay and the addition, via ruminal infusion, of increasing amounts of nitrogen supplementation in order to gradually raise the CP level of the basal diet in intervals of 2% points, that is, + 2, +4, + 6 and + 8%. Samples of the feeds offered, and the leftovers were collected daily during the five days of collection to determine the nutrient intake, as well as the total collection of feces to determine the apparent digestibility of the nutrients. The amount of fecal dry matter excreted was estimated by the concentration of Indigestible Acid Detergent Fiber (ADFi), Indigestible Neutral Detergent Fiber (NDFi), Indigestible Dry Matter at 244 h (DMi 244 h) and Indigestible Dry Matter at 264 h (DMi 264 h). Among the evaluated markers, DMi 264 h had the lowest accuracy in estimating fecal excretion and nutrient digestibility. For the goat species, the markers ADFi and DMi 244 h proved to be able to adequately predict fecal excretion and digestibility indices, while NDFi stood out for both species. Among the evaluated markers, NDFi is the one that most accurately estimates the nutrient digestibility of the diet for goats and sheep.

Forage cactus as an additive in corn without the cob silages of feedlot sheep diets.

This study aimed to assess the impact of adding forage cactus as an additive to the production of corn silage without the cob on the performance of feedlot sheep and subsequent silage losses. The experimental design was completely randomized, consisting of three treatments: corn silage without cob; 0% = 100% corn plant without the cob; 10% = 90% corn plant without cob + 10% forage cactus; 20% = 80% corn plant without cob + 20% forage cactus. Significant effects were observed for dry matter intake (P = 0.0201), organic matter (P = 0.0152), ether extract (P = 0.0001), non-fiber carbohydrates (P = 0.0007). Notably, nutrient digestibility showed significant differences in organic matter (P = 0.0187), ether extract (P = 0.0095), neutral detergent fiber (P = 0.0005), non-fiber carbohydrates (P = 0.0001), and metabolizable energy (P = 0.0001). Performance variables, including total weight gain (P = 0.0148), average daily weight gain (P = 0.0148), feeding efficiency, and rumination efficiency of dry matter (P = 0.0113), also exhibited significant effects. Consequently, it is recommended to include 20% forage cactus in corn silage, which, based on natural matter, helps meet animals' water needs through feed. This inclusion is especially vital in semi-arid regions and aids in reducing silage losses during post-opening silo disposal.

Spineless cactus use management on microbiological quality, performance, and nutritional disorders in sheep.

The physically effective neutral detergent fiber content alone has not been able to explain the appearance of diarrhea in ruminants fed diets with large volumes of spineless cactus, so the proliferation of enterobacteria in spineless cactus may be associated with cases of diarrhea in sheep. In the in vitro test, used two varieties of spineless cactus, both of which were chopped to particles of 4 and 2 cm2. For the in vivo test, 15 lambs were allocated to three treatment groups, namely, spineless cactus crushed and immediately supplied to the animals; spineless cactus crushed 8 h before supply; and silage of spineless cactus. The variables evaluated were dry matter intake, weight gain, fecal score, hemogram, and fecal colony count. In the in vitro test, higher Enterobacteriaceae and lactic acid bacteria counts were found both at 12 h and 24 h when the spineless cactus was crushed to 2 cm2 in both varieties. The sheep fed the spineless cactus crushed 8 h prior to supply showed the highest Enterobacteriaceae count in the feces (8.48 CFU/g), compared to animals fed silage of spineless cactus (4.95 CFU/g). It can thus be concluded that the management of spineless cactus influences the development of total and fecal coliforms, especially when it is chopped to 2 cm2 and exposed to the environment for periods longer than 7 h, and that the bacterial population can be controlled by administering the spineless cactus in the form of silage.