Two experiments, namely the situ nylon bag technique and the in vitro gas production technique, were carried out to determine the correlations between the in situ ruminal degradability and the in vitro gas production of different forages, and to predict the ruminal degradability of the forages using the gas production parameters. Forage samples from Napier grass (Pennisetum purpureum), Guinea grass (Panicum maximum), Para grass (Brachiaria mutica), Leucaena (Leucaena leucocephala), Rain tree (Samanea saman), and Gliricidia (Gliricidia sepium) were incubated in the rumen of three rumen-cannulated buffaloes using the in situ nylon bag technique for 3, 6, 12, 24, 48, and 72 h. The six forage samples were also subjected to the in vitro gas production analysis following the modified methods developed by Menke & Steingass (1988), along with 30 other commonly used forages in the Philippines. Both experiments followed a randomized complete block design. Their dry matter (DM), organic matter (OM), neutral detergent fiber (NDF), and crude protein (CP) degradation kinetics and effective degradability (ED) as well as the gas production parameters were then estimated. Results revealed that the ED of each nutrient was found to be moderately to strongly correlated with some of the gas production times and estimated gas parameters. The predictor models generated using the gas production parameters for the ED of DM, OM, and NDF were sufficiently strong (R 2 = 0.740, p value= 0.0002; R 2 = 0.659, p value= 0.0009; and R 2 = 0.813, p value < 0.0001, respectively) while that of CP was only moderate (R 2 = 0.500, p value= 0.0055). It was concluded that the relationship between the two techniques is sufficiently strong and therefore the gas production parameters can be used to predict the in situ ruminal nutrient degradability of forages.

This study compared the composition, yield, and freezing point of buffalo colostrum and milk collected on the 30 th , 60 th , and 90 th day of lactation from purebred Murrah and its crosses with the Philippine Carabao. A total of 133 milk samples were collected from 36 buffaloes (20 purebred Murrah and 16 "Murrah x Carabao" crosses) and evaluated for fat, protein, and lactose content, solids non-fat (SNF), total solids, and freezing point. Colostrum contained significantly (p<0.05) more protein, SNF, total solids, and higher freezing point, but less moisture and lactose, and were produced in lower amounts than milk obtained on different days of lactation. Fat percentage was not significantly different (p>0.05) between colostrum and milk. Colostrum from Murrah buffaloes had more protein but less fat and colostrum yield than "Murrah x Carabao" crosses. Among crossbred buffaloes, the F2 "75% Murrah -25% Carabao" crosses produced more colostrum than F1 "50% Murrah -50% Carabao" (p<0.05). Older buffaloes also produced more colostrum. Milk parameters were similar for Murrah and "Murrah x Carabao" crosses, except for test-day milk yield, which was significantly higher in "Murrah x Carabao" crosses. The F1 crossbred buffaloes had milk containing more lactose and SNF, but lower freezing point than milk from F2 crossbred buffaloes. Buffaloes, already with more lactations, had higher test-day milk yield but with lower fat and total solids. High monthly temperature reduced test-day milk yield. In conclusion, breed differences, age at calving, number of lactations, and high monthly temperature may have caused changes in the composition and yield of buffalo colostrum and milk.

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