Effects of grain source and marginal change in lucerne hay particle size on feed sorting, eating behaviour, chewing activity, and milk production in mid-lactation Holstein dairy cows

2014 ◽  
Vol 98 (6) ◽  
pp. 1110-1116 ◽  
Author(s):  
S. M. Nasrollahi ◽  
G. R. Ghorbani ◽  
M. Khorvash ◽  
W. Z. Yang
Keyword(s):  
Particle Size ◽  
Dairy Cows ◽  
Milk Production ◽  
Eating Behaviour ◽  
Marginal Change ◽  
Chewing Activity ◽  
Holstein Dairy Cows

scholarly journals Effects of Alfalfa Particle Size and Specific Gravity on Chewing Activity, Digestibility, and Performance of Holstein Dairy Cows

2004 ◽  
Vol 87 (11) ◽  
pp. 3912-3924 ◽  
Author(s):  
A. Teimouri Yansari ◽  
R. Valizadeh ◽  
A. Naserian ◽  
D.A. Christensen ◽  
P. Yu ◽  
...  
Keyword(s):  
Particle Size ◽  
Specific Gravity ◽  
Dairy Cows ◽  
And Performance ◽  
Chewing Activity ◽  
Holstein Dairy Cows

Genetic variation of rectal temperature and its relationship to milk production in Holstein dairy cows

2009 ◽  
Vol 2009 ◽  
pp. 63-63
Author(s):  
S Khalajzade ◽  
N Emam Jomeh ◽  
A Salehi ◽  
A Moghimi Esfandabadi
Keyword(s):  
Heat Stress ◽  
Dairy Cows ◽  
Milk Production ◽  
Heat Tolerance ◽  
Rectal Temperature ◽  
Weather Factors ◽  
And Performance ◽  
Very High ◽  
Selection Of ◽  
Holstein Dairy Cows

Milk production is significantly decreased by thermal stress. The survival and performance of an animal during heat stress periods depend on several weather factors, especially temperature and humidity. Researchers reported dramatic decreases in milk production as temperature rose above 30 degree of centigrade. Very high environmental temperature is common during the summer months in Iran. Rectal temperature is as indicator of heat tolerance and has been the most frequently used physiological variable for estimating heat tolerance in cattle. Some dairy cows are more heat tolerant and productive when subjected to heat stress. Identification and selection of heat stress resistant cattle offers the potential to increase milk yield in tropical environment. The aim of the present study was to estimate genetic parameters of heat tolerance and its relationship to milk production in Holstein Dairy Cows in Iran.

Effect of first 60-day cumulative milk yield on days open in Holstein dairy cows in Iran

2007 ◽  
Vol 2007 ◽  
pp. 148-148
Author(s):  
A. Heravi Moussavi ◽  
M. Danesh Mesgaran ◽  
T. Vafa
Keyword(s):  
Dairy Cattle ◽  
Dairy Cows ◽  
Milk Production ◽  
Milk Yield ◽  
Dairy Farm ◽  
Reproductive Efficiency ◽  
Root Cause ◽  
Principal Factors ◽  
Days Open ◽  
Holstein Dairy Cows

Reproduction and milk production are the principal factors that are influencing dairy farm profitability. The dairy industry in Iran has changed dramatically in the last decade. The shift toward more productive cows and larger herds in Iran is associated with a decrease reproductive efficiency (Heravi Moussavi et al., 2004). Increased knowledge about the principal causes of reduced fertility is essential. The root cause of the declining fertility is probably a combination of a variety of physiological and management factors that have an additive effect on reproductive efficiency. Dairy cattle are inseminated and pregnancy is established while dairy cows are lactating. Based on the analyses of large datasets, there is clearly an antagonistic relationship between milk production and reproduction in dairy cattle (Lucy, 2001). It was shown that the hazard ratio for cumulative first 60-day milk yield and conception in high producer cows was 8 percent less than the others and also high milk yield was a risk factor for several reproductive disorders (Grohn and Rajala-Schultz, 2000). The objective of this study was to evaluate the effect of first 60-day cumulative milk yield on days open in Iranian Holstein dairy cows.

Effects of lucerne hay and barley grain particle sizes on chewing activity, rumen pH and milk composition of Holstein dairy cows

2007 ◽  
Vol 2007 ◽  
pp. 130-130
Author(s):  
A.R. Bayat ◽  
R. Valizadeh ◽  
A.A. Nasserian
Keyword(s):  
Particle Size ◽  
Dairy Cows ◽  
Milk Fat ◽  
Milk Composition ◽  
Barley Grain ◽  
Particle Sizes ◽  
Milk Fat Depression ◽  
Rumen Ph ◽  
Maize Grain ◽  
Chewing Activity

NRC (2001) recommended 250 g/kg dietary neutral detergent fibre (NDF) with a minimum of 190 g/kg dietary forage NDF to prevent milk fat depression. This recommendation does not account for the differences in forage particle size. The forage particle size requirements of dairy cows fed barley grain-based diets can differ from those fed maize grain-based diets (Yang and Beauchemin, 2006). The objective of this experiment was to evaluate the effects of lucerne hay and barley grain particle sizes on chewing activity, rumen pH, milk yield and milk composition using barley grain-based diets.

Sign in / Sign up

Export Citation Format

Share Document