Productive responses of early lactating dairy cows to ruminally protected methionine supplemention [electronic resource].

Includes references.

Increased milk production requires high intakes of crude protein in the diet, and/or improved supply and profiles or amino acids (AA) delivered to the duodenum. in order to meet animal needs for milk and milk component synthesis. The objectives of this experiment were to estimate the impacts of a rumen protected methionine (RPM) supplementation on dry matter intake as well as milk production and composition and blood metabolites in high producing Holstein dairy cows at early lactation (62±4.1 days in milk). Forty early lactating multiparous Holstein dairy cows (570±13.5 kg) were randomly assigned into two experimental groups and fed a total mixed ration (TMR) without (CTRL) or with 240 g/pen/d of the RPM supplement (to deliver J2 g methionine/cow/d) for 10 weeks. The results of the current experiment showed that RPM supplementation did not influence dry maner intake (DMI) in early lactating cows (24.4 vs 24.1 kg/d), but improved (P<0.05) milk yield (37.9 verSus 38.9 kg/d), as well as the yields of milk protein (1.250 versus 1.344 kg/d) and milk solid not-fat (SNF; 3.310 versus 3.560 kg/d). The inclusion of RPM in TMR of dairy cows enhanced the feed efficiency and achieved daily net profit of 6.62 EGP per cow.

Summary in Arabic.

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