ABSTRACT
OBJECTIVE: The daily maximum temperature and seawater level continuously increase as global warming continues. We examined the adaptability and production performance of heat-stressed goats with a supply of low-saline drinking water. METHODS: Twelve Kacang and Kacang Etawah cross goats were exposed to two climatic conditions (control, 25°C to 33°C, 83% relative humidity [RH], temperature humidity index [THI]: 76 to 86; and hot environment, 26°C to 39°C, 81% RH, THI: 77 to 94) and two salt levels in drinking water (0% and 0.4% NaCl). The experimental design was a Latin Square (4×4) with four treatments and four periods (28 days each). RESULTS: Temperature of the rectal, skin, and udder, and respiration rate rose, reached a maximum level on the first day of heat exposures, and then recovered. Plasma sodium rose at 0.4% NaCl level, while the hot environment and salinity treatments increased the drinking water to dry matter (DM) intake ratio. Water excretion was elevated in the hot environment but lowered by the increase in salinity. Total lying time increased, whereas change position frequency decreased in the hot condition. Lying and ruminating and total ruminating time increased and explained the enhanced DM digestibility in the hot conditions. CONCLUSION: The goats exhibited a high level of plasma sodium as salinity increased, and they demonstrated physiological and behavioral alterations while maintaining their production performances under increasing daily maximum temperatures.
ABSTRACT
BACKGROUND AND AIM: Feeding ruminants must notice the degradability of feed, especially protein. Microbial rumen requires ammonia from rumen degradable protein (RDP) beside that ruminant require bypass protein or rumen undegradable protein (RUP) and microbial crude protein. The aim of the study was to discover the best RDP:RUP ratio in beef cattle diets commonly used by Indonesian farmers using an in vitro methodology. MATERIALS AND METHODS: Samples of Pennisetum purpureum, Leucaena leucocephala, Indigofera zollingeriana, cassava, maize, palm kernel cake, rice bran, and tofu waste were formulated into dietary treatments (dry matter [DM] basis). All experiments were carried out using a 3×3×2 factorial, randomized block design with three replications. Treatments consisted of three protein levels (12%, 14%, and 16%), two energy levels (65% and 70%), and three RDP:RUP ratio levels (55:45, 60:40, and 65:35). The experimental diets were incubated in vitro using buffered rumen fluid for 48 h at 39°C. After incubation, the supernatants were analyzed to determine pH, ammonia concentration, total volatile fatty acid (VFA), and microbial protein synthesis. The residues were analyzed to determine DM, organic matter, protein, and RUP digestibility. RESULTS: Increased protein, energy, and RDP levels increased digestibility, ammonia concentrations, total VFAs, and microbial protein synthesis (p<0.05), while rations with 16% protein lowered these parameters (p<0.05). CONCLUSION: Increased dietary protein (from 12% to 14% DM), energy (from 65% to 70% DM), and RDP (from 55% to 65% crude protein [CP]) levels increased nutrient digestibility, ammonia concentration, total VFA levels, and microbial protein synthesis. The diet containing 14% DM dietary protein and 70% DM energy, which contained 55%, 60%, or 65% CP RDP optimally increased nutrient digestibility, ammonia concentration, total VFA levels, and microbial protein synthesis. Thus, feed based on these RDP:RUP ratios can optimize ruminant productivity.
ABSTRACT
AIM: This research aimed to discover the chemical composition, as well as the content of the degradable and undegradable protein of the ruminant feed commonly used as cattle feed by Indonesian farmers. MATERIALS AND METHODS: In this study, Pennisetum purpureum, Leucaena leucocephala, Indigofera zollingeriana, Gliricidia sepium, cassava, maize, palm kernel cake, and rice bran were used as feed. Chemical composition was determined by proximate and Van Soest analyses performed in triplicate. Dry matter and organic matter digestibility, as well as the rumen degradable proteins (RDP) and rumen undegradable proteins (RUP) contents, were determined in vitro using the Tilley and Terry method. RESULTS: The results showed that more proteins can be obtained from legumes than from grass or concentrates. The highest protein amount was obtained from I. zollingerian (31.22%), while the lowest protein amount was obtained from cassava (3.59%). Dry matter digestibility ranged from 18.53% (rice bran) to 49.21% (G. sepium). Organic matter digestibility ranged from 35.71% (cassava) to 59.57% (I. zollingerian). Rice bran had the highest RDP from concentrate (73.26%), whereas I. zollingerian had the highest RDP from forage (74.72%). The highest RUP from concentrate was obtained from palm kernel cake (61.01%), and the highest RUP from forage was obtained from L. leucocephala (49.23%). CONCLUSION: The preparation of ruminant livestock rations must be based on RDP and RUP to meet the needs of both the rumen microbes and host animals. Information regarding the RDP and RUP of feeds is still limited, making this study useful in the preparation of ruminant livestock rations based on RDP and RUP ratios.
