نتایج جستجو برای: cattle breeding

تعداد نتایج: 104336  

Journal: :Applied animal behaviour science 2000
Grignard Boissy Boivin Garel Le Neindre P

In cattle, a gregarious species, the social group influences individual stress responses to fear-eliciting situations. As handling can be stressful for farm animals, it can be hypothesised that social partners modify individual responses to handling. The present experiment investigated the effect of the presence or absence of social partners on behavioural reactions of beef calves in a handling...

2015
Yuri T. Utsunomiya Ana M. Pérez O'Brien Tad S. Sonstegard Johann Sölkner José F. Garcia

The bovine species have witnessed and played a major role in the drastic socio-economical changes that shaped our culture over the last 10,000 years. During this journey, cattle "hitchhiked" on human development and colonized the world, facing strong selective pressures such as dramatic environmental changes and disease challenge. Consequently, hundreds of specialized cattle breeds emerged and ...

Journal: :Journal of applied animal welfare science : JAAWS 2009
Paul A Rees

This study examined the distribution of 495 Asian elephants (Elephas maximus) and 336 African elephants (Loxodonta africana) in 194 zoos, most of which were located in Europe (49.1%) and North America (32.6%). Cows outnumbered bulls 4 to 1 (Loxodonta) and 3 to 1 (Elephas). Groups contained 7 or fewer: mean, 4.28 (sigma = 5.73). One fifth of elephants lived alone or with one conspecific. Forty-s...

Journal: :Memorias do Instituto Oswaldo Cruz 2006
Gema Alvarez García Inmaculada López Pérez Elisabeth Innes Esther Collantes Fernandez Aurora Fernandez Garcia Mercedes Gomez Bautista Luis Miguel Ortega Mora

A Neospora caninum 17 kDa protein fraction (p17) has been described as an immunodominant antigen (IDA) under reducing and non-reducing conditions. The aim of the present study was to investigate the diagnostic utility of p17 in cattle. In order to achieve this, p17 was purified by electroelution from whole N. caninum tachyzoite soluble extract and a p17-based Western blot (WB-p17) was developed...

Journal: :علوم دامی ایران 0
محمد رزم کبیر اردشیر نجاتی جوارمی محمد مرادی شهر بابک امیر رشیدی محمد باقر صیاد نژاد

data related to holstein dairy cattle from 1987 to 2004 were obtained from animal breeding center of iran to estimate the genetic and phenotypic trends. variance components and genetic parameters of the first lactation records were estimated using restricted maximum likelihood method and aireml algorithm through matvec program. animal breeding values were predicted through multiple-trait animal...

Fayaz Ahmad Bhat Hiranya Kumar Bhattacharyya, Syed Akram Hussain

The objective of the present study was to determine the grades of nonspecific bacterial infection of genitalia of repeat breeding cattle by a simple and rapid test under field condition. For this purpose, a total of 100 crossbred Jersey cows comprising of 80 repeat breeding animals presented for treatment and 20 normal cyclic (control group) animals presented for artificial insemination at thei...

Journal: :Journal of animal science 1998
G L Bennett S E Echternkamp K E Gregory

Genetic increases in twinning of cattle could result in increased frequency of triplet or higher-order births. There are no estimates of the incidence of triplets in populations with genetic levels of twinning over 40% because these populations either have not existed or have not been documented. A model of the distribution of litter size in cattle is proposed. Empirical estimates of ovulation ...

Journal: :Animal reproduction science 2000
P I Rekwot D Ogwu V O Sekoni E O Oyedipe

Sixty-four zebu cows, comprised mainly of Bunaji cattle aged between 3 and 7 years old, were involved in an intensive artificial insemination programme. The study was conducted during the breeding period (May-October), and cows were inseminated with freshly prepared Friesian semen when they stood to be mounted by the vasectomised bull or herdmates. Fertility was measured by serum progesterone (...

Journal: :Journal of the South African Veterinary Association 2004
E Mokantla C M E McCrindle J P Sebei R Owen

The communal grazing system is generally understood to have a low input, low output type of management. However, the actual inputs and outputs of the farmers are not well known and the farmers are often unaware of their problems. Although the causes of low calving percentage are well understood in commercial beef farming enterprises in South Africa, the same is not true for communal farming sys...

2000
Bjørg Heringstad Gunnar Klemetsdal John Ruane

The literature concerning selection for mastitis resistance in dairy cattle is reviewed and the reasons for including mastitis resistance in dairy cattle breeding programs are described. The current situation in Denmark, Finland, Norway and Sweden is described with emphasis on the data recording schemes and the choice of models used for breeding value estimation. The use of clinical mastitis da...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید