Blood serum free amino acids pattern in newborn calves on colostral diet and orally treated with zeolite

Abstract

Oral zeolite treatement effects on the blood serum free amino acid pattern in newborn calves was investigated. The total number of 30 newborn Holstein calves of both sexes, weighting 35±3 kg (mean±SD), were immediately after parturition separated from their dams and placed in individual pens. Calves were divided in two experimental groups, 15 calves each. All calves were bottle-fed twice/ day (1.5 L/meal) during the first 48 hours after delivery, in 12 hour intervals, with their mother's first (during 24 hours postpartum) or second colostrum (at 24-48 hours postpartum), starting two hours after delivery. Zeolite suspension (20 mL, 25% suspension in distilled water) was added to every meal for treated calves. Colostrum samples were collected from six cows at 0-12h and 24h after delivery. Total and colostral whey protein concentrations were determined using the colorimetric method. Blood samples were taken from the jugular vein of calves at 6, 16, 30 and 40 hours after birth. After spontaneous coagulation at room temperature blood serum was separated and stored at -20°C until analyzed. Total protein concentration was determined by the colorimetric method. Blood serum immunoglobulin G (IgG) concentrations were determined using single radial immunodiffusion (sRID) plates. Pooled blood serum free amino acids (aspartic acid - Asp, glutamic acid - Glu, serine - Ser, histidine - His, glycine - Gly, threonine - Thr, alanine - Ala, proline - Pro, tyrosine - Tyr, arginine - Arg, valine - Val, methionine - Met, Leucine - Leu, Isoleucine - Ile, phenylalanine - Phe) were identified and quantified using high-performance liquid chromatography (HPLC, GBC Australia). Total and colostral whey protein concentrations were significantly higher in the first colostrum and decreased between 50-75% at 24-48 hours later on. Mean blood serum IgG concentration was significantly increased at 6 and 16 hours in the treated calves (26±7:20±5 and 55±15:42±13 g/L, p<0.05). Blood serum free amino acids (AA) first were separated at nonessential and essential AA (NEAA and EAA, respectively), both being increased at all time intervals after birth in treated calves. However, when the pooled blood serum free AA were clustered according to polarity and electrical charge and presented as relative values (% of the control group values) at the 6h there was a massive increase of polar positive (Arg, His), polar neutral (Ser, Thr, Tyr) and nonpolar neutral free AA (except Met). The minimal effect of oral zeolite treatment was on the negative polar blood serum free AA concentration (Asp and Glu).