Responses in urea and true protein of milk to different protein feeding schemes for dairy cows.
ABSTRACT Four multiparous Holstein cows were used in a 4 x 4 Latin square to investigate the effects of protein concentration, degradability, and quality on plasma urea concentration and milk N constituents. Diets varied in the amount and proportion of RDP and RUP relative to NRC requirements: diet 1, excessive RDP, deficient RUP; diets 2 and 3, balanced for RDP and RUP; and diet 4, excessive RDP, balanced for RUP. Diet 3 was formulated for optimal AA balance as predicted by the Cornell Net Carbohydrate and Protein System. Diets contained 34% corn silage, 19% alfalfa haylage, and 49% concentrate (DM basis). Concentrates varied in amounts of urea and soybean, corn gluten, and fish and blood meals. Concentrations of urea N and NPN in milk varied among diets: diet 1, 19 and 34 mg/dl; diet 2, 16 and 31 mg/dl; diet 3, 15 and 30 mg/dl; and diet 4, 23 and 39 mg/dl, respectively. Increases in NPN concentration were attributed to increases in the urea fraction of NPN. Intake of RUP and AA balance influenced milk true protein content; diet 1, 2.89%; diet 2, 2.90%; diet 3, 3.01%; and diet 4, 2.95%. the proportions of true protein and urea in milk are influenced by CP concentration, protein type, and protein quality.
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ABSTRACT: This study estimated the effect of levels of rubber seed kernel (RSK) in concentrate on feed intake, rumen fermentation, and blood metabolites in goats. Four, Thai Native × Anglo Nubian crossbred growing male goats with an average body weight of 21 ± 1 kg were housed in metabolism crates and randomly assigned according to a 4 × 4 Latin square design with four consecutive 21-d periods which consisted of 14-d adaptation and 7-d data collection. The dietary treatments were as follows: T 1 = RSK at 0% (control), T 2 = RSK at 10%, T 3 = RSK at 20%, and T 4 = RSK at 30% of DM basis, respectively. Signal hay was offered on an ad libitum basis as the roughage. Based on this experiment, there were no significant differences (p>0.05) among treatment groups regarding roughage intake whereas overall means for daily DMI (total DMI, % BW and g/kg BW 0.75) were significantly affected (p<0.05) by levels of RSK and DMI were increased quadratically with increasing level of RSK in diets. T 4 (30% RSK) had lower (p<0.05) than other treatments. The ruminal pH, NH 3 -N, BUN, blood glucose, and packed cell volume (PCV) were similar among treatments (p>0.05). In conclusion, RSK levels were up to 20% in concentrate could be efficiently utilized for goats fed on signal hay.The 15th AAAP Animal Science Congress, Thammasat University (Rangsit Campus), Bangkok/Pathum Thani, Thailand.; 11/2012
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ABSTRACT: The effects of different levels of crude protein (CP) and cottonseed meal replacing for soybean meal in cassava chips and rice straw-based diets for mid-lactating cows (100-150 day in milk [DIM]), were studied using 32 multiparous Holstein Fresian crossbred dairy cows. Diets containing 10.5, 12.5, 13.7, 14.4% CP of the rations and 0, 12.1, 14.9, 17.8% cottonseed meal were fed to cows for 60 days. Thirty two cows were randomly divided into four dietary treatments using a Randomized complete block design. Four dietary treatments were offered in the form of total mixed ration (TMR) with concentrate to roughage (chopped rice straw) at 60:40 and offered ad libitum. Dry matter (DM) and neutral detergent fiber (NDF) intakes tended to linearly increase with increasing dietary CP levels. Intakes and digestibility of crude protein increased linearly with increasing dietary CP level (pAsian Australasian Journal of Animal Sciences 01/2005; 18(4). · 0.64 Impact Factor
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ABSTRACT: To investigate the effects of inclusion of palm kernel cake (PKC) in the diets on intake, digestibility, rumen ferment-ation characteristics, nitrogen balance and microbial N supply, five goats (initial BW = 20±1 kg) were randomly assigned to a 55 Latin square design to receive five diets, T 1 = concentrate with 15% PKC, T 2 = 25% PKC, T 3 = 35% PKC, T 4 = 45% PKC and T 5 = 55% PKC, of dietary dry matter, respectively. Plicatulum hay was offered ad libitum as the roughage. A metabolism trial lasted for 21 days during which live weight changes and feed intakes were measured. Based on this experiment, there were no significant differences (p>0.05) among treatment groups regarding dry matter (DM) intake and digestion coefficients of DM, organic matter, crude protein, neutral detergent fiber and acid detergent fiber, except in T 4 and T 5 (45 and 55% PKC) which had lower (p<0.01) than other treatments. Rumen parameters: temperature, pH, NH 3 -N, blood urea nitrogen and blood glucose, packed cell volume, volatile fatty acids, rumen microorganism populations and N retention were similar among treatments (p>0.05), however the concentration of total volatile fatty acids and protozoal populations were slightly lower for goats fed inclusion of 45-55% PKC as compared with other treatments. Based on this experiment, it could be concluded that the optimal level of PKC in concentrate should be 15-35% for goats fed with plicatulum hay and that it may be an effective means of exploiting the use of local feed resources for goat production.