Genetic and permanent environmental variations in daily milk yield and milk flow rates in Hungarian Holstein Friesian

Effects of daily exogenous oxytocin injections on milk production and fat yield in holstein cows

effect of bataine and sulphate supplement on wool and milk characteristics and lambs performance in naine ewes

تعداد 20 رأس میش نژاد نائینی 6+-24 ماهه، با میانگین وزن 2/3-+40 کیلوگرم، همراه با 20 رأس بره های آنها در قالب طرح کاملا تصادفی اثر بتائین و مکمل سولفات بر خصوصیات شیر و پشم و عملکرد بره ها بررسی شد. میش ها بطور تصادفی در چهار تیمار قرار گرفتند. تیمارها عبارت بودند از: 1-گروه شاهد 2-بتائین (05/0 درصد ماده خشک) 3-سولفات (24/0 سولفور درصد ماده خشک 4-بتائین هرماه با سولفات. جیره غذائی طبق nrc با مح...

Risk factors and milk yield losses associated with lameness in Holstein-Friesian dairy cattle.

Weekly locomotion scores on a scale of 1 to 5 were used to investigate the relationship between cattle lameness, management systems and the impact of lameness on milk production. The data were 14026 locomotion scores from 248 Holstein-Friesian cows. Cows were managed in two groups, XE (high-concentrate feed and housed indoors all year) and XM (low-concentrate feed and outdoors in summer). Analy...

Causal Relationships Between Milk Yield, Body Condition Score and Fertility in Italian Holstein Friesian Dairy Cattle

The aim of the study was to explore genetic relationship among milk yield, body condition score (BCS) and pregnancy status (PR) in Italian Holstein cows using a recursive effects model. Two recursive models and a multiple-trait model were compared in four different subsets of data. The antagonistic effect of milk yield on BCS and PR was confirmed, as well as the positive relationship between BC...

Genetics of milk yield and fertility traits in Holstein-Friesian cattle on large-scale Kenyan farms.

Purebred Holstein-Friesian cows are the main exotic breed used for milk production on large, medium, and small farms in Kenya. A study was undertaken on seven large-scale farms to investigate the genetic trends for milk production and fertility traits between 1986 and 1997 and the genetic relationships between the traits. This involved 3,185 records from 1,614 cows, the daughters of 253 sires. ...