scholarly journals Analysis of Non-Genetic Factors Affecting Calving Interval and Post-Partum Traits in Egyptian Buffaloes

1998 ◽  
Vol 35 (1) ◽  
pp. 597-607
Author(s):  
Vallabh Pawar ◽  
Nikhil Dangar ◽  
Gaurav Pandya ◽  
Balkrishna Brahmkshtri ◽  
Vishnu Kharadi ◽  
...  

2007 ◽  
Vol 6 (sup2) ◽  
pp. 1351-1353
Author(s):  
O. Colmenares ◽  
P. Monasterio ◽  
P. Herrera ◽  
B. Birbe ◽  
N. Martínez

2008 ◽  
Vol 53 (No. 7) ◽  
pp. 284-291 ◽  
Author(s):  
M. Fiedlerová ◽  
D. Řehák ◽  
M. Vacek ◽  
J. Volek ◽  
J. Fiedler ◽  
...  

The objective of this study was to analyze the effects of non-genetic factors affecting calving difficulty in the Holstein population of the Czech Republic for subsequent compilation of the model for genetic evaluation as well as for herd management practice. Calving difficulty recorded in 1997–2006 was assessed in three categories: 1 = normal, 2 = hard pull, 3 = complicated. The original observations were transformed to an underlying normal scale. A data set containing 409 255 records was analysed by a linear model with fixed effects of season, parity of dam, sex of calf and Holstein gene proportion. All these effects were significant, and their appropriate categorization was considered. Analyses of additional factors such as gestation length, age at first calving and preceding calving interval were performed. The results revealed that gestation length was in a non-linear relationship with calving difficulty. A higher risk of difficult calving was associated with short or long gestation and with a prolonged preceding calving interval in multiparous cows. Calving difficulty should be adjusted for these factors. A decreased risk of difficult calving could be achieved by an altering of calving interval and age at first calving as a management tool.


Author(s):  
M. Srinivasa Reddy ◽  
V. Jagadeeswary ◽  
J. Sai Prasanna

Background: Environmental factors play a major role and influence the economically important traits in dairy animals. The present investigation was undertaken to study the influence of season on production and reproduction traits of graded Murrah buffaloes reared under farm conditions. Methods: The data pertaining to 164 graded Murrah buffaloes was utilized to study influence of seasons on various climatic factors like maximum, minimum and mean temperature, relative humidity (morning and evening), rainfall, sunshine, wind speed, evaporation and production and reproduction traits like lactation length, lactation yield, days to attain peak yield, persistency, calving interval, birth weight and number of lactations. Result: The present investigation revealed significant effect of season on all the meteorological parameters, production and reproduction parameters studied. The correlations among meteorological parameters and production and reproduction traits were also significant.


2019 ◽  
Vol 29 (1) ◽  
pp. 13
Author(s):  
Lisa Praharani

Efforts to increase cattle production can be done through increasing the population and productivity of cattle, one of which is through the birth of two offsprings per parent (twin). The incidence of twinning in cattle ranged 1-10%, and influenced by genetic/breed, parity, management, season of breeding. This paper presented factors and technology that increase twinning rate and the impacts of twin births in cattle. There are genetic and non genetic factors affecting twinning rate. Increased twin births can be done through some technologies such as selection, reproduction and management. The problems in twinnings are the high incidence of abortion, early embryonic loss, distochia, retained placenta, metabolic disorders, and ketosis resulting in longer calving interval. Intensive management to dam bearing twins can reduce the problems. Economically, the profits of twinning are different between beef and dairy cattle. Twin births give benefit to beef cattle farming through the increase in total weaning per cattle. The pros and cons of twin births occur in dairy cows farming, especially on milk production.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Jessica Tyrrell ◽  
Jie Zheng ◽  
Robin Beaumont ◽  
Kathryn Hinton ◽  
Tom G. Richardson ◽  
...  

AbstractLarge studies such as UK Biobank are increasingly used for GWAS and Mendelian randomization (MR) studies. However, selection into and dropout from studies may bias genetic and phenotypic associations. We examine genetic factors affecting participation in four optional components in up to 451,306 UK Biobank participants. We used GWAS to identify genetic variants associated with participation, MR to estimate effects of phenotypes on participation, and genetic correlations to compare participation bias across different studies. 32 variants were associated with participation in one of the optional components (P < 6 × 10−9), including loci with links to intelligence and Alzheimer’s disease. Genetic correlations demonstrated that participation bias was common across studies. MR showed that longer educational duration, older menarche and taller stature increased participation, whilst higher levels of adiposity, dyslipidaemia, neuroticism, Alzheimer’s and schizophrenia reduced participation. Our effect estimates can be used for sensitivity analysis to account for selective participation biases in genetic or non-genetic analyses.


1954 ◽  
Vol 1 (1) ◽  
pp. 44-52 ◽  
Author(s):  
S. C. Reed ◽  
W. Reed ◽  
J. D. Palm

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