University:
Sam Houston State University
Course:
BIOL 2413 | General Zoology
Academic year:

2020
Views:

257

Pages:

10
Author:

GalacticGuru

Length of Estrus Cycle  Cattle:  Sheep:  Swine:  Horses: 19 to 23 Days 14 to 19 Days 19 to 23 Days 10 to 37 Days Duration of Estrus Cycle  Cattle:  Sheep:  Swine:  Horses: 12 to 18 Hours 24 to 36 Hours 48 to 72 Hours 3 to 8 Days Signs of Estrus Swollen vulva  Mucous discharge  Restless behavior  Female receptivity to male  Specific Signs of Estrus Cattle: Visually active mounting  Sheep: Few external signs  Swine: Brace with pressure to back, vocal grunting  Horses: Tease with Stallion and will go nose to nose  Gestation Length  Cattle:  Swine: 283-285 Days 147 Days 114 Days(3months 3weeks 3days)  Horses: 336 Days  Sheep: Partition Names in Species  Cattle:  Sheep:  Swine:  Horses: Calving Lambing Farrowing Foaling Signs of Parturition Distended abdomen  Mammary development & milk secretion  Swollen vulva and relaxed pelvic ligaments  Mucous discharge  Relentlessness and separation from group  Labor and Contractions  Signs of Parturition     Appearance of placental membrane Expulsion of fetus Expulsion of placental membrane Bonding behavior of offspring and mother (will vary between species) Male Transfer of Sperm  Two different ways  Let the male and female naturally engage.    Male seeks out female in Estrus All controlled by male and female interaction Artificial Insemination (AI)    Human transfers semen past female cervix Human is in control of male product and female interaction No contact between male and female Artificial Insemination (AI) Pros Conception rate is high  Extends use of superior males    Reduce incidence of venereal diseases   Individual straw per female Improves record keeping and mgt.   One ejaculate can fertilize many females Know exactly who the father is Can accelerate genetic improvements