VMD 513: Pet animal Breeding, Management, Nutrition and Health Care (1+1)

OVULATION AND ITS DETECTION

• Ovulation occurs 24 to 72 hours after the LH surge from the pituitary gland. The number of eggs released varies somewhat depending on the age and breed of the female.
• In general, smaller breeds produces fewer eggs than larger breeds.
• At the time of ovulation, the ova are still immature and do not complete meiosis until approximately 24 hours after ovulation. The maturation process takes 2 to 3 days.
• The behavioral cues are helpful in providing a general time frame of ovulation. Most bitches will accept the approach of male and will stand to bred several days prior to ovulation.
• If behavioral cues alone are being used to determine breeding dates, the bitch should be bred on the first day of acceptance of the male, then 2 and 4 days later.
• Other methods of determining ovulation are exfoliation cytology and sequential measurement of serum progesterone levels.
• The vaginal exfoliation cytology during anestrus, the vaginal lining is with few cell layer composed of small cuboidal cells, when estrogen level increases, this layer thickened and the cells develop into stratified squamous epithelium.
• As proestrus proceeds, the thickening of the epithelial layer pushes the cells lining the lumen further away from their blood supply. This avascular state causes characteristic cellular changes, and eventually cellular death and exfoliation(sloughing of the cells).