Ansci C4

• Aurochs (Bos primigenius) - Domesticated during stone age
• Yach (Poephagus grunniens) - mountains of tibet
• Bos banteng(Bali cattle) - India
• Bos frontalis (gayal) - india
• Bos indicus - Indian or african origin
• 277 breeds worldwide
• British breeds - Angus, Red Angus, Galloway, Hereford, Shorthorn,.
• Continental breeds - Charolais, Chianina, Gelbvieh, Limousin, Normande, Piedmontese, Pinzgauer, Simmental
• Shorthorn - durham
• American breeds - Amercan Brahman, Beef Master, Braford, Brahmasin, Brangus, Charbray, Gelbray, Santa Gertrudis, Texas Long Horn.
• Other breeds - Murray gray, Wagyu, Brahman.
• Bos taurus - european origin
• Breeding - defined as the controlled propagation of cattle to improve

  qualities desirable to the farmer.
• Qualitative traits - show discontinuous variations
• Quantitative traits - show continuous variations between the

  extremes
• Random mating - this means each

  possible mating in a population has the same probability

  or occurrence.
• Inbreeding - matings of closely related individuals within a breed
• Close breeding - Mating of close relatives e.g. father-daughter; sonmother; brother-sister
• Line Breeding - Breeding of not so close relatives, e.g. cousins
• Strain - a very mild form of inbreeding which leads to increase

  homozygousity within the strain in the long term
• Crossbreeding - mating of individuals from two or more established purebreds
• Hybrid vigor - as the average quality of the first

  generation exceeding the average of the two parental

  breeds.
• Systematic crossbreeding - two or more breeds are involved in a breeding program

  lasting several years.
• Upgrading - the mating of purebred sires to nondescript or native
• Estrous cycle - Begins at puberty which continues to occur in a regular

  pattern
• Hypothalamus - major role: control the estrous cycle
• Estrous cycle has 4 phases
• Proestrus - Initial development follicles
• Estrus - follicles becoming mature
• Metestrus - secreting progesterone
• Diestrus - longest phase of the cycle
• FSH and LH - released from anterior pituitary gland in cyclic

  manner.
• Follicle Stimulating Hormone (FSH) -responsible for development of ovarian follicles
• Estrogen - acts on the development of mammary ducts, and

  sensitize and increase the vascular supply of the

  uterus.
• Luteinizing Hormone (LH) - causes ovulation of matured follicle containing the

  egg.
• Progesterone - causes the growth of mammary glands b
• Androgen - causes the development and maintenance of

  the secondary sexual traits of males