24 research outputs found
Veal calf performance in response to concentrate diets of different rumen degradable protein content
(South African J of Animal Science, 2000, 30, Supplement 1: 58-59
Veal calf performance in response to concentrate diets of different of rumen degradable protein.
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The effect of age on <I>in sacco</I> estimates of rumen dry matter and crude protein degradability in veal calves.
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The effect of dietary rumen degradable protein content on veal calf performance
The objective of this study was to determine the undegradable dietary protein requirements of veal calves. Two experiments were carried out with Holstein bull calves from 3-10 days of age until slaughter at 20 weeks of age. Both experiments were divided into starter and finishing periods. Calves were offered starter pellets on an ad lib. basis from seven days of age. Diets were formulated to be iso-nitrogenous and iso-caloric, and differed in undegradable dietary protein content. In Experiment 1 calves were randomly assigned to one of three dietary treatments containing low (LD), medium (MD) or high (HD) levels of rumen degradable protein. In Experiment 2 calves received a starter diet containing either a high or a low level of rumen degradable protein. At the end of the starter period animals from both treatment groups were re-assigned at random to finisher diets containing either low or high rumen degradable protein levels, resulting in four treatment combinations, viz. LL, LH, HL and HH. There were no treatment differences for feed intake, body weight gain or feed efficiency during the starter period of either experiment. During the finishing period (weeks 12-20) of Experiment 1, calves receiving the LD diet had higher average daily gains than calves receiving the HD treatment. Feed conversion ratio for the LD treatment was also better than for the other two treatments. During the finishing period (weeks 11-20) of Experiment 2 the feed conversion ratio tended (P < 0.10) to differ between treatments: feed conversion ratio for the LL and HL treatments was more favourable than that for the LH treatment. Feed conversion ratio for the HH treatment was intermediate, and did not differ from that of the LL, HL or LH treatments. The level of crude protein degradability appears to have no effect on calf performance during the starter period, but it may, however, be beneficial to feed finisher diets with a lower crude protein degradability during the finisher period.Articl
The effect of dietary rumen degradable protein content on veal calf performance.
AgriwetenskappeVeekundige WetenskappePlease help us populate SUNScholar with the post print version of this article. It can be e-mailed to: [email protected]
The effect of age on in sacco estimates of rumen dry matter and crude protein degradability in veal calves
CITATION: Holtshausen, L. & Cruywagen, C. W. 2000. The effect of age on in sacco estimates of rumen dry matter and crude protein degradability in veal calves. South African Journal of Animal Science, 30(3):212-219.The original publication is available at https://www.sasas.co.zaThis study was conducted to determine whether rumen dry matter and crude protein degradability in calves aged 8-10 weeks differs from that in mature cows. Five Holstein bull calves were rumen-fistulated at six weeks of age and were used in consecutive weekly 24 h trials from 8-20 weeks of age. Dry matter and crude protein degradability of two starter and two finisher veal calf diets of high or low rumen degradable protein content were estimated from 24 h in sacco incubation. Rumen pH and concentrations of volatile fatty acids and ammonia-nitrogen were determined on a weekly basis. Three rumen-fistulated Holstein cows were also used to evaluate dry matter and crude protein degradabilities of the diets. Estimates of dry matter degradability obtained from calves differed between the low and high degradability diets within weeks. Dry matter degradability differed between the starter and finisher diets (weeks 10 and 11) and remained fairly constant from week 11 to week 20. Crude protein degradability in calves also differed between the low and high degradability diets within weeks. Crude protein degradability increased up to week 12 and then remained constant until week 20. Dry matter and crude protein degradability estimates for the starter diets were both lower than the corresponding values obtained with cows, while estimates for finisher diets were similar. There were no clear trends over time for rumen pH, volatile fatty acid concentrations and ratios, or for rumen ammonia-nitrogen concentrations ion calves. These values showed a degree of variation between weeks and were similar to literature values for mature ruminants.https://www.sasas.co.za/journals/the-effect-of-age-on-in-sacco-estimates-of-rumen-dry-matter-and-crude-protein-degradability-in-veal-calves/Publisher's versio