Theerayut Juntanam

The use of cassava as a feed resource is the main focus of strategies that aim to increase the efficiency of beef cattle. In this study, the ratio of fresh cassava tops to roots (CTR) was 1:1, 1:2, 1:3, and 1:4 w/w, in addition to the incorporation of yeast and lactic acid bacteria (YL). CTRS was inoculated in vitro with rumen fluid and a substrate mixture to evaluate the gas production and fermentation quality. In vivo, crossbred beef cattle were randomly allocated to three dietary treatments: a control group and two groups that received total mixed ration (TMR) silage with either 35% or 70% of the concentrate replaced with CTRS. This study found that the levels of crude protein and condensed tannins (CTs) in CTRS were relatively increased by the addition of cassava tops (p < 0.05), while the fermentation pH decreased as the proportion of cassava roots increased. CTRS significantly enhanced in vitro dry matter digestibility, cumulative gas at 96 h, gas production kinetics, and MBP (p < 0.05), especially in the 1:2 group. In the in vivo experiment, CTRS increased DM intake, CP, and propionic acid concentration compared to the control group and showed great potential for improving NDF digestibility. Moreover, when the concentrate in the TMR silage was substituted with CTRS and offered to crossbred beef cattle, it increased ruminal NH₃-N and blood glucose levels (p < 0.05). The TMR silage substituted with 70% CTRS reduced the feed cost by 50.54% (p < 0.05). Our study findings suggest that optimizing the inclusion of CTRS in TMR silage could be a viable strategy for beef producers aiming to enhance cattle performance and profitability.

The current issue of ruminant methane emissions is still being researched by animal nutritionists in an effort to find new approaches. In this study, five beef cattle were randomly assigned in a 5 × 5 Latin square design to examine the effects of supplementation with high-tannin and -polyphenol plant materials on nutrient utilization, rumen fermentation, and nitrogen partitioning. Cattle offered total mixed ration (TMR) silage diets with or without tannin-rich tree leaf or plant herbs, such as Piper sarmentosum Roxb., Cymbopogon citratus (DC.) Stapf, Anacardium occidentale L., and Careya arborea Roxb., were supplemented at a dose of 10 g/d. Prior to TMR feeding, the animals’ meals were supplemented with 10 g of fortified plant materials twice a day, along with 100 g of rice bran. The animals in the control group received only 100 g of rice bran and no other plant materials. The result showed that there was no difference in nutrient intake or digestibility between the supplemented and control groups. Although the effect of ruminal pH, NH₃-N, Total VFA, acetate (C2), and butyrate (C4) was not significant (p > 0.05), the proportion of propionate (C3) tended to increase with supplementation (p = 0.07). There was no difference in the excretion of purine derivatives or the amount of microbial nitrogen supply, even though supplemented animals had significantly lower protozoal populations than the control group (p < 0.05). Moreover, when A. occidentale or C. arborea was added to the TMR silage diet, the nitrogen intake and retention increased considerably, although total nitrogen excretion decreased. In this approach, the leaves of Anacardium occidentale L. and Careya arborea Roxb. were particularly promising for strategic supplementation.