Influence of nutritional restriction during late gestation on production measures and passive immunity in beef cattle.
A 2-yr study was conducted to examine the effects of nutritional restriction of beef cows during the last 90 d of gestation on neonatal immunity and production. Cows were fed corn silage, soybean meal diets; dietary treatments consisted of 1) control (CO), 100% of the NRC (1984) requirements for protein and energy, or 2) restricted (RS), 57% of the NRC requirements for energy and protein. All cows received adequate amounts of this diet postpartum. Each year, 26 Angus cows were grouped by age and weight:height ratio (WT:HT) and allotted randomly to treatments. Calves born to dams within each nutritional treatment group were allotted to one of two colostral treatments: 1) colostrum from their dam, or 2) colostrum from a cow from the other nutritional treatment group. Calves from restricted dams had higher cortisol (33.8 vs 26.1 ng/ml) and lower triiodothyronine (T3) (3.82 vs 4.01 ng/ml) concentrations (P less than .05). Maternal nutrition did not affect either colostrum immunoglobulin G (IgG) concentration (43.0 vs 39.5 mg/ml for RS and CO, respectively) or the calves' serum IgG concentration (19.06 vs 20.17 mg/ml IgG at 24 h for RS and CO, respectively). Yet, calves fed colostrum from restricted cows tended to have lower serum IgG concentration (17.2 vs 22.0 mg/ml IgG at 24 h).
Dept. of Anim. Sci., Virginia Polytechnic Institute and State University, Blacksburg 24061.
R L
RL
Hough
F D
FD
McCarthy
H D
HD
Kent
D E
DE
Eversole
M L
ML
Wahlberg
D000818:Animals; D001724:Birth Weight; D002417:Cattle / Q000254:growth & development / Q000276:immunology*; D003126:Colostrum / Q000276:immunology; D004044:Dietary Proteins / Q000008:administration & dosage; D002149:Energy Intake; D005260:Female; D005508:Food Deprivation / Q000502:physiology*; D006854:Hydrocortisone / Q000097:blood; D007112:Immunity, Maternally-Acquired; D007074:Immunoglobulin G / Q000032:analysis; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000276:immunology / Q000502:physiology*; D011897:Random Allocation; D014284:Triiodothyronine / Q000097:blood; D015430:Weight Gain
D004044:Dietary Proteins; D007074:Immunoglobulin G; D014284:Triiodothyronine; D006854:Hydrocortisone