Protected methionine as a methyl-group donor for dairy cows fed diets with different starch sources in the transition period

Abstract

) was supplemented to rations containing a high proportion of starch easily (barley) or slowly (maize) fermented in the rumen, fed to preand postpartum dairy cows to study its effect on milk yield and composition, metabolic profi le and reproduction. The experiment was carried out on 24 Polish Holstein-Friesian cows, divided 21 days before expected parturition into 3 groups of 8 animals and fed individually. Protected methionine was added to the rations from day 21 before, until 21 day after parturition, but the performance of cows was controlled up to the end of week 12 of lactation.Protected methionine had no effect on milk yield and composition, metabolic profi le, body weight, body condition score, or reproduction indices. Methionine supplementation increased feed intake before parturition (P<0.01) and blood glucose concentration before parturition and on day 2 after calving (P<0.03 and P<0.01, respectively). The starch source had no infl uence on the studied parameters.There was also no statistically signifi cant interaction between the level of protected methionine supplementation and starch sources. These results do not support the hypothesis that feeding cows increased amounts of starch digested in the small intestine together with protected methionine can 5 Corresponding autor: e-mail: jstrzet@izoo.krakow.pl Journal of Animal and Feed Sciences, 18, 2009, 28-41 29 STRZETELSKI J.A. ET AL.lower energy defi ciency and mobilization of energy reserves as well as decrease liver lipidosis by increasing the synthesis of very-low-density lipoproteins.

The effect of rumen-protected methionine and choline on plasma metabolites of Holstein dairy cows

“…In addition, RPM and RPC had a positive effect on milk lactose concentration. In contrast to the current study, Strzetelski et al (2009) reported no significant effect of RPM on the milk content of lactose in dairy cows.…”

“…Feeding RPM increased prepartum plasma glucose levels in the current study and under such conditions gluconeogenesis may be enhanced, or glucose uptake by peripheral tissues is reduced. Strzetelski et al (2009) reported that addition of RPM resulted in a significant increase in blood serum glucose content before calving, which is in accordance with the findings of the current study.…”

“…In contrast to the results of the current study for postpartum DMI, several studies have reported that the supplementation of RPC (Pinotti et al 2002;Piepenbrink & Overton 2003;Zahra et al 2006;Davidson et al 2008) in the diet of dairy cows had no effect on DMI. Several studies have reported that the supplementation of RPM had no effect on DMI (Overton et al 1996;Girard et al 2005;Lara et al 2006), but Strzetelski et al (2009) reported a significant effect of RPM on DMI. Feeding RPC increased postpartum DMI and this was due to higher milk yield in RPC-fed cows than cows fed other treatments.…”

“…As in the current study, Davidson et al (2008) reported that milk yield was significantly higher for RPC-fed cows than cows fed other treatments and Erdman & Sharma (1991) reported that RPC-fed cows tended to produce more milk and more FCM. Also, Strzetelski et al (2009) and Overton et al (1996) reported that yields of milk, CP and percentages of fat and CP in milk were not affected by RPM. However, in contrast to the results of current study, Janovick Guretzky et al (2006) reported RPC did not affect the daily yields of 35 g/kg FCM, fat and protein for Holstein and Jersey cows during the periparturient period.…”

Digestibility, ruminal fermentation, blood metabolites and antioxidant status in ewes supplemented with DL‐methionine or hydroxy‐4 (methylthio) butanoic acid isopropyl ester

“…() who reported that serum glucose concentrations tended to increase slightly as a result of HMB supplementation in the diets of pre‐partum dairy cows. The increase in serum glucose levels after supplementation with HMBi is confirmed by the findings of previous studies (Piepenbrink et al., ; Strzetelski et al., ).…”