帯広畜産大学 学術情報リポジトリ >
030大学院畜産学研究科 >
03010学位論文(修士) >

このアイテムの引用には次の識別子を使用してください: http://ir.obihiro.ac.jp/dspace/handle/10322/913

タイトル: 乳牛における分娩後の濃厚飼料増給率と栄養代謝因子および繁殖性の関係
その他のタイトル: Effects of Increasing Rate of Dietary Concentrate During the Early Lactation on Metabolic Status and Reproductive Performance in Postpartum Dairy Cows
著者: 石原, 美紀
ISHIHARA, Miki
発行日: Jan-2007
出版者: 帯広畜産大学
抄録: The objective of this study was to establish strategies of feeding management, which could achieve high milk production and high fertility, and also prevent production diseases. The experiment was conducted to compare the effects of the two types of the increasing rate of transition diets fed during the postpartum period on hormones, metabolic status and reproductive performance in postpartum dairy cows. Prepartum Holstein dairy cows (n=10) were assigned to two groups of five each. Beginning at 14 d before expected calving, cows were held into the door-feeder pens, and after parturition, one group was fed diets with concentrate increased at the rate of 1kg/2 d until 2.5 wk postpartum (Rapid Group ; RG), and the other group was fed diets with concentrate increased at the rate of 1kg/4 d until 5 wk postpartum (Gradual Group ; GG). Amount of milk production was recorded daily, and amounts of feed intake and remain were also recorded daily from 2 wk prepartum to 7 wk postpartum. Rumen fluid for ruminal VFA and pH determinations were collected weekly from 1 wk prepartum to 6wk postpartum, and blood samples for several hormones and metabolites analyses were collected weekly from 2 wk prepartum to parturition, collected daily from parturition to 5 wk postpartum and collected 32 weekly after 5 wk postpartum until 14 wk. There were no significant differences in milk production, DMI, insulin and IGF-1 concentrations between two treatments. The dietary ratio of forage to concentrate had a significant difference between treatments from 1 wk postpartum until 3 wk (P<0.05), however, the ratios ranged from 0.4 to 0.5, which meant that ruminal fermentation was normal. RG had significantly higher concentrations of VFA on the 3 wk postpartum compared to GG (P<0.05), and also had significantly higher concentrations of glucose and significantly lower concentrations of GH and beta-hydroxybutyrate during the treatment period (P<0.05). As for reproductive performance, days to first ovulation and days to first AI did not differ between treatments, but RG had significantly better results on number of AI to pregnancy and conception rate at 120 days postpartum, compared to GG (P<0.05). There was no difference in DMI between treatments. However, RG had larger amount of TDN from concentrate, which could cause better energy status and may result in better reproductive performance, compared to GG. Besides, even RG could have normal ruminal fermentation as they were able to consume enough forage to keep it properly, which could maintain rumen health and achieve good fertility.
記述: 畜産衛生学専攻
平成18年度修士学位論文
Master Course of Animal and Food Hygiene
URI: http://ir.obihiro.ac.jp/dspace/handle/10322/913
出現コレクション:03010学位論文(修士)

このアイテムのファイル:

ファイル 記述 サイズフォーマット
i070331syuuron.pdf722.85 kBAdobe PDF見る/開く

このリポジトリに保管されているアイテムはすべて著作権により保護されています。

 

Valid XHTML 1.0! DSpace Software Copyright © 2002-2006 MIT and Hewlett-Packard - ご意見をお寄せください