Calf Mortality in Cow Herds Floron C. Faries, Jr., DVM, MS Professor and Extension Program Leader Texas AgriLife Extension Service Texas A&M System College Station, TX

Calf Scours

Causative Disease AgentsCalf Ages Bacteria E. coli<5 da C. perfringens B, C5-30 da C. perfringens D>30 da Salmonella>15 da Viruses Rotavirus5-15 da Coronavirus5-15 da BVD>30 da

Protozoa Cryptosporidia5-30 da Coccidia>15 da

Calf AgesDisease Agents <5 daE. coli 5-15 daRotavirus Coronavirus C. perfringens B, C Cryptosporidia

15-30 daC. perfringens B, C Cryptosporidia Coccidia Salmonella >30 daCoccidia Salmonella C. perfringens D BVD

Disease Agent Sources Carrier Cows, Heifers Manure – Vulva, ground (teats, haircoat, grass, hay) Diseased Calves Scours – Ground (haircoat, grass, hay)

Calf Pathology/Signs Intestinal Mucosa Damage Irritation, necrosis, toxins Diarrhea, Dehydration Malabsorption Hypersecretion Colon fermentation, fluid retention

Electrolyte Imbalance Acidosis – bicarbonate loss Body Weakness Reduced Nursing Possible Septicemia

Calf Septicemia

Causative Disease Agents E. coli Lepto

Calf Pneumonia

Causative Disease Agents Bacteria Pasteurella H. somnus Viruses IBR PI 3 BRSV BVD

Stress Weather Weaning

Disease Incidence Factors Carrier Cows, Heifers, Calves - Disease agents Contaminated Environment - Disease agents Stressed Cows, Heifers - Suppressed immunity Disease agent shedding Reduced colostrum quantity Reduced colostrum globulins (quality)

Thin Cows, Heifers – Low Energy Diet Reduced colostrum quantity Reduced colostrum globulins (quality) Heifers Colostrum – Lower quantity, quality Calves Late Colostrum Intake No local, systemic immunity >6 hrs, >24 hrs after birth

Calves, Low Colostrum Intake Weak local, systemic immunity < 10% body weight – First 24 hrs Weak local immunity <10% body weight – Second day <10% body weight – Third day Stressed Calves Dystocia, cold stress Colostrum intake – Low, late Heat stress Globulin absorption - Reduced

Disease Management Practices Sanitary Measures Maternity pasture 7 da pre-calving to 1 da post-calving 15 acres per 75 females Rotate pastures anually

Nursery pasture 3 wks 20 acres per 75 pairs Rotate pastures annually Nursing pasture 3 wks post-calving to weaning Prevent overcrowdedness

Treatment pasture/pen Isolate diseased calves 1 wk minimum Haying, Supplement Feeding Facilities Rotate locations Manure removal

Shelter Facilities Manure removal Prevent Stress in Pregnant Cows, Heifers Provide shelter, wind breaks Energy diet (grain) – last trimester Assure calf nursing Within 6 hours of birth

Identify Reasons for Late/Low Colostrum Intake/Absorption Abandoned calf Calf can’t find teat Big teats Weak calf Calf kicked off Calf not mothered Udder not distended Caesarean cow/heifer

Bottle Feed Non-nursing Calf Within 6 hrs of Birth Colostrum quantity – 5% body weight Next 18 – 24 hrs Colostrum quantity – 5% body weight Days 2 and 3 Colostrum quantity – 10% body weight

Disease Diagnostic Procedures Laboratory Tests of Fresh Scour Specimen Bacteria culture/antibiotic sensitivity Virus isolation Protozoa demonstration

Disease Vaccination Practices Pre-calving Vaccination of Pregnant Cows, Heifers Procedures Intramuscularly, subcutaneously 2 doses, 2-3 and 6-8 wks before calving 1 dose annually

Products E. coli K-99 Bacterin Rotavirus/Coronavirus Vaccine (Killed, Modified live) C. perfringens C,D (B) Bacterin (7-way Blackleg) Lepto (5–way) IBR/PI 3 /BRSV/BVD Pasteurella H. somnus

Vaccination of Calves at Calving Procedures Orally 1 dose at birth Products E. coli K-99 Monoclonal Antibody Rotavirus/Coronavirus Vaccine (Modified live)

Disease Treatment Practices Dehydrated Calves Procedures Orally, intravenously, intramuscularly Products Oral electrolytes – 1 to 2 qts. Every 6 to 8 hrs. Intravenous electrolytes Antibiotics – E. coli septicemia

Genetic Defects Homozygous Recessive Genes Double Recessive Genes Passed by both Parents

Anal Atresia Scrotal Hernia Cryptorchidism Cleft Palate Over-shot Jaw Mulefoot Dwarfism Five-legged Supernumerary Teats No Teats No Tail

Twinning Genetic Inheritable (1% Rate) Free Martins Lighter Birth Weights Heavier Dual Weaning Weights Retained Placentas Dystocias Perinatal Calf Mortality Reduced Fertility Increased Nutritional Requirements