Lecture on Parturition in Domestic, Farm, and Pet Animals

Introduction

• Presenter: Prof. Govind Narayan Purohit, Head of Department of Veterinary Gynecology and Obstetrics, College of Veterinary and Animal Science, Rajasthan University of Veterinary and Animal Sciences, Bikaner, Rajasthan
• Topic: Parturition in Domestic, Farm, and Pet Animals

Parturition Overview

• Definition: Delivery of the fetus through the birth canal after gestation.
• Birth Canal Components: Uterus, cervix, and vagina, supported by the pelvic bones.

Pre-Parturient Care

• General Care: Animals moved to appropriate environments prior to parturition.
  • Calves: Shift to calving box 1-2 months before calving.
  • Mares: Quiet environment; use of CCTV for observation to avoid disturbance.
  • Cows: Low energy, high fiber diet; monitor dietary cation-anion ratio.
  • Sheep: High energy diet for twin-carrying ewes.
  • Bitches: Diet with 1-1.8% calcium and 0.8-1.6% phosphorus.

Vaccination

• Pregnant Bitches:
  • Only use registered safe killed or intranasal vaccines.
  • Keep up to date with live vaccines in non-pregnant bitches for future protection.
  • Killed parvovirus vaccines 2+ weeks before pups are born to enrich colostrum.
• Pregnant Mares:
  • Vaccinate against Equine Herpes Virus 1 & 4 during 5th, 7th, and 9th months.
  • Tetanus vaccination annually, 4-6 weeks before foaling.
• Sheep and Goats:
  • Vaccinate for Clostridial diseases and tetanus 4-6 weeks before parturition.

Deworming

• Cattle: Safe, except albendazole during first 45 days.
• Mares: Safe with most commercial dewormers; administer ivermectin within 12 hours post-foaling.
• Bitches: Deworm prior to mating, at 5 and 8 weeks of gestation; use safe products like fenbendazole.
• Sheep and Goats: Use coccidiostat and effective anthelmintics; avoid albendazole during first trimester.

Signs of Approaching Parturition

• Cattle:
  • Udder enlargement: 4 months in heifers, 1-2 weeks pre-partum in adult cows.
  • Vaginal discharge: Starts at 6-7 months, increases near parturition.
  • Sacro-sciatic ligaments: Relax 24-48 hours pre-partum.
  • Behavioral changes: Raised tail, and anorexia.
• Bitches: Drop in rectal temperature, nesting behavior.
• Mares: Colostrum secretion (waxing of the teats), drop in secretion of electrolytes.

Initiation of Parturition

Theories

1. Physical Factors:

• Increased fetal size leading to uterine irritability.
• Uterine distension reverses progesterone block.
• Placental deterioration affects fetal nutrition.

2. Biochemical Factors:

• Increased CO2 tension and fetal activity increases uterine contractility.
• Fetal antigens lead to collagenase release and blood supply interruption.

3. Neuroendocrine Factors:

• Fetal cortisol converts progesterone to estrogen, releases prostaglandins.
• Increase in ACTH and CRH promotes cortisol release, increasing uterine contractility.

4. Maternal Factors:

• Reversal of progesterone block, increased myometrial contractility.
• Release of relaxin and prostaglandins dilates birth canal and increases contractions.
• Oxytocin release increases myometrial contractions.

Stages of Labor

1. First Stage:

• Myometrial contractions, increased uterine pressure, abdominal discomfort, cervical dilation.
• Ends with rupture of first water bag (chorioallantois).

2. Second Stage:

• Strong uterine contractions, appearance of fetus wrapped in amnion through vulva.
• Delivery of the fetus: 30-180 minutes (species-dependent).

3. Third Stage:

• Expulsion of placenta within 1-12 hours in cattle.
• Increased uterine contractions post-fetus birth.
• Suckling induces oxytocin release, aiding uterine contractions.

Duration of Labor by Species

• Cows: 1st stage: 4-24 hrs, 2nd stage: 0.5-3 hrs, 3rd stage: 8-16 hrs.
• Buffalo: Similar to cows.
• Mares: 2nd stage: 30 minutes, 3rd stage: <3 hrs.
• Bitches: 1st stage: 4-24 hrs, 2nd stage: 2 hrs (first puppy), subsequent puppies: 5-60 minutes.
• Camels: 1st stage: 3-48 hrs, 2nd stage: 5-18 mins, 3rd stage: <4 hrs.

Physiology of Fetal Orientation

• Fetus reorients from back position to head-foot alignment for successful delivery.
• Importance varies by species; less critical in pigs with multiple fetuses.

Fetal Changes Pre- and Post-Parturition

Fetal Circulatory Changes

• Closure Requirements: Ductus venosus, ductus arteriosus, foramen ovale.

Pre-Parturient Changes

• Lungs: Increased surfactants reduce alveoli surface tension.
• Endocrine Activity: Increased T3 and catecholamines.
• Liver: Enhanced glycogen reserves for glucose production.

Visual Examples

• Images demonstrating visual signs of parturition in various animals.

Conclusion

• Encourage sharing of the lecture and subscription to YouTube channel for more content.
• Thanks for attending.