Risk factors for subclinical hypocalcaemia, and associations between subclinical hypocalcaemia and reproductive performance, in pasture-based dairy herds in New Zealand

2018 ◽  
Vol 67 (1) ◽  
pp. 12-19 ◽  
Author(s):  
KI Roberts ◽  
S McDougall
Keyword(s):  
Risk Factors ◽  
New Zealand ◽  
Reproductive Performance ◽  
Dairy Herds ◽  
Subclinical Hypocalcaemia

High genetic merit and high-producing dairy cows in commercial Australian herds don't have substantially worse reproductive performance

2001 ◽  
Vol 26 (2) ◽  
pp. 305-311
Author(s):  
J.M. Morton
Keyword(s):  
Risk Factors ◽  
Reproductive Performance ◽  
Dairy Herd ◽  
Quality Data ◽  
Dairy Herds ◽  
Stepwise Logistic Regression ◽  
High Quality Data ◽  
Genetic Merit ◽  
Milk Volume ◽  
Fat Yield

AbstractThe National Dairy Herd Fertility Project (renamed the InCalf Project) consists of two large, prospective observational studies conducted in commercial dairy herds from 4 Australian states. The project aims to identify factors associated with variation in reproductive performance between cows and herds. The larger of the two studies included over 33,000 cows and 168 herds. The database has undergone extensive error checking and correction resulting in high quality data. Large variations in reproductive performance were observed between cows and herds, indicating that there are important risk factors for reproductive performance and that cows and herds are exposed to varying combinations of these risk factors. Models for several reproductive outcomes were constructed using multivariable stepwise logistic regression. No significant associations were detected between any measures of cow genetic merit and 6 week in-calf rate. Neither milk volume nor protein yield were significantly associated with 6 week in-calf rate. A weak negative association was detected between fat yield in the first 120 days of lactation and 6 week in-calf rate. However, differences in estimated 6-week in-calf rate between moderate and high producing groups (2 to 5 percentage points) were small when contrasted against the 63 percentage point range in performance observed between herds (23% to 86%).

scholarly journals Bayesian analysis of herd-level risk factors for bovine digital dermatitis in New Zealand dairy herds

2019 ◽  
Vol 15 (1) ◽  
Author(s):  
Dan Aaron Yang ◽  
M. Carolyn Gates ◽  
Kristina R. Müller ◽  
Richard A. Laven
Keyword(s):  
Risk Factors ◽  
New Zealand ◽  
Bayesian Analysis ◽  
Dairy Herds ◽  
Digital Dermatitis ◽  
Herd Level

Reproductive performance of seasonal-calving, pasture-based dairy herds in four regions of New Zealand

2013 ◽  
Vol 62 (2) ◽  
pp. 77-86 ◽  
Author(s):  
TS Brownlie ◽  
JM Morton ◽  
C Heuer ◽  
J Hunnam ◽  
S McDougall
Keyword(s):  
New Zealand ◽  
Reproductive Performance ◽  
Dairy Herds

scholarly journals A case-control study to identify risk factors for acute salmonellosis in New Zealand dairy herds, 2011–2012

2016 ◽  
Vol 144 (10) ◽  
pp. 2154-2164
Author(s):  
M. A. STEVENSON ◽  
P. L. MORGAN ◽  
J. SANHUEZA ◽  
G. E. OAKLEY ◽  
R. S. BATEMAN ◽  
...  
Keyword(s):  
Risk Factors ◽  
New Zealand ◽  
Case Control Study ◽  
Multivariable Analysis ◽  
Palm Kernel ◽  
Case Control ◽  
Dairy Herds ◽  
Herd Level ◽  
Supplementary Feed ◽  
Control Study

SUMMARYIn late 2011 the New Zealand Ministry for Primary Industries reported an increase in confirmed laboratory diagnoses of salmonellosis in dairy herds. To identify risk factors for herd-level outbreaks of salmonellosis we conducted a case-control study of New Zealand dairy herds in 2011–2012. In a multivariable analysis, use of continuous feed troughs [adjusted odds ratio (aOR) 6·2, 95% confidence interval (CI) 2·0–20], use of pelletized magnesium supplements (aOR 10, 95% CI 3·3–33) and use of palm kernel meal as a supplementary feed (aOR 8·7, 95% CI 2·5–30) were positively associated with a herd-level outbreak of salmonellosis between 1 July 2011 and 31 January 2012. We conclude that supplementary feeds used on dairy farms (regardless of type) need to be stored and handled appropriately to reduce the likelihood of bacterial contamination, particularly from birds and rodents. Magnesium supplementation in the pelletized form played a role in triggering outbreaks of acute salmonellosis in New Zealand dairy herds in 2011–2012.

Sign in / Sign up

Export Citation Format

Share Document