Performance, digestibility, microbial protein synthesis, and body composition of Brangus x Zebu steers on tropical pasture receiving supplementation

Effect of Palm Kernel Cake Supplementation on Voluntary Feed Intake, In Situ Rumen Degradability and Performance in Buffaloes in the Eastern Amazon

The objective was to evaluate the effects of palm kernel cake (PKC) supplementation on voluntary feed intake, in situ rumen degradability and performance in the wettest (WS-January to June) and less rainy seasons (LR-July to December) in the eastern Amazon. A total of 52 crossbred buffaloes that were neither lactating nor gestating were used, with 24 for the LR, aged 34 ± 04 months and an initial average weight of 503 ± 48 kg, and 24 for the WS aged 40 ± 04 months with an average weight of 605 ± 56 kg. The four treatments (levels of PKC in relation to body weight) were distributed in a completely randomized design, with 0% (PKC0), 0.25% (PKC0.2), 0.5% (PKC0.5) and 1% (PKC1) with six repetitions. The animals were housed in Marandu grass paddocks, intermittently, with access to water and mineral mixture ad libitum. Degradability was evaluated by the in situ bag technique in four other crossbred buffaloes with rumen cannulae, in a 4 × 4 Latin square (four periods and four treatments). The inclusion of PKC increased supplement consumption and production of ether extracts and reduced the intake of forage and non-fibrous carbohydrates. The dry matter degradability of Marandu grass was not affected; however, the fermentation kinetics in neutral detergent fiber (NDF) differed between the treatments. The co-product dry matter colonization time was greater in PKC1 and the highest effective degradability rates were from PKC0, but the productive performance of the animals was not influenced. Supplementation of buffaloes with PKC is recommended for up to 1% of body weight.

Shorter Grazing Time and Supplementation Are Beneficial for Gastrointestinal Tract Development and Carcass Traits of Growing Lambs

The effects of restricted grazing durations on the gastrointestinal development and carcass quality of growing lambs are poorly understood. In this study, 32 lambs were randomly assigned to four groups (n = 8, body weight = 21.86 kg) corresponding to 2, 4, 8 and 12 h of grazing per day. When off-pasture, all lambs were housed and fed concentrate and hay. When the grazing time decreased from 12 h to 2 h, the abomasum weight and large intestine length decreased (p = 0.019; p = 0.069). Compared to lambs grazed for 12 h, animals grazed for 2−4 h had a greater villus height and villus-to-crypt ratio in the duodenum, jejunum and ileum segments (p < 0.05); the 2 h lambs had superior carcass quality and a smaller diameter and area of the gluteus medium muscle fibers (p < 0.05), with no significant change after 4 h of grazing. The results indicated that shorter grazing times and supplementation were beneficial for the gastrointestinal tract development and carcass quality of growing lambs. Therefore, a better grazing management approach in Inner Mongolia could be to restrict the grazing of lambs to 4 h per day instead of grazing for more extended periods.