Environmental and Genetic Factors Affecting on Semen Quality in Iranian Holstein Bulls

environmental and genetic factors affecting on semen quality in iranian holstein bulls

the objective of this study was to evaluate the importance of environmental and genetic factors affecting semen quality; sperm volume (sv), sperm concentration (spco), total sperm (ts), fresh sperm motility (fsm), total fresh motile sperm (tfms), post thaw sperm motility (ptsm), total post thaw motile sperm (tptms), number of produced payout (npp), number of fresh motile sperm in each milt ejac...

Genetic and environmental effects on semen quality of Austrian Simmental bulls

Semen production data from an Austrian AI centre collected between 2000 and 2004 were analysed. In total, 12,746 ejaculates from 301 AI bulls were examined considering different effects on ejaculate volume, sperm concentration, percentage of viable spermatozoa in the ejaculate, total spermatozoa per ejaculate and motility. The model included the fixed effects of age of bull, collection interval...

Environmental factors and semen quality.

OBJECTIVES An increasing number of reports suggest that chemical and physical agents in the environment, introduced and spread by human activity, may affect male fertility in humans. This article aims at evaluating the impact of environmental exposures (pesticides, phthalates, PCBs, air pollution, trihalomethanes (THMs), mobile phones) on semen quality, by reviewing most recent published litera...

Factors affecting the quality of semen of A.I. dairy bulls in South Africa

evaluation of none genetic and genetic factors affecting on stillbirth in iranian holstein dairy cattle

stillbirth is defined as a calf death just prior to, during, or within 24 to 48 h of parturition. the exact cause of calf death in dairy cows in this period of time is unknown. the objective of this study was to investigate about the effective factors on stillbirth and also to estimate some of the genetic parameters in iranian dairy holsteins. data in the first and second lactation that have be...

Risk factors affecting the culling of Iranian Holstein dairy cows

This experiment was conducted to determine the association between several risk factors which may affect culling of the Iranian Holstein cows. The data consisted of 329,772 lactation records collected by the Animal Breeding Center of Iran (2003 to 2012).The logistic regression was applied to investigate the associations between the response variable, the risk of culling, and predictor variables...