Efeito do escore da condição corporal ao parto e estádio de maturidade sobre o status metabólico e composição do leite de búfalas Murrah.

Abstract

The purpose of this study was to evaluate the influence of body condition score (BCS) at calving and maturity stage on the metabolic status of female Murrah buffaloes in the transition period. In the experiment 1 were used thirty-seven pregnant buffaloes (multiparous) were selected and monitored during the transition period based on their body condition score and on the estimated calving date. Two groups were formed: 1) buffaloes with a BCS > 3.5 (n = 17); this group was classified and named ‘high BCS at calving’ (HBCS); and 2) buffaloes with a BCS ≤ 3.5 (n = 20); this group was classified and named ‘low BCS at calving’ (LBCS). All animals were monitored during the last 30 days of pregnancy and the first 70 days post-calving and kept in the same environment and under the same feeding and management conditions. Mean values for BCS at calving were 2.98 ± 0.9 (mean ± SD) and 4.21 ± 0.9 (mean ± SD) for the HBCS and LBCS groups, respectively. In the experiment 12 were thirty pregnant buffaloes were selected and monitored during the transition period based on their calving number and on the estimated calving date. Two groups were formed: 1) Primiparous buffaloes (n= 15) and; 2) Multiparous buffaloes (n= 15). The HBCS group showed higher milk fat content (p = 0.007) and milk fat yield (p = 0.027) and a higher concentration of milk urea nitrogen (p = 0.001) than LBCS buffaloes, which in turn had a lower urine pH value (p = 0.033) than HBCS buffaloes in the pre-calving period (7.86 for HBCS vs. 7.76 for LBCS). The HBCS animals had a higher concentration of erythrocytes (p = 0.001) and hematocrit (p = 0.012) post-calving and a higher hemoglobin concentration (p = 0.004) pre-calving. The multiparous buffaloes showed higher milk contents of fat (P= 0.019), protein (P= 0.045), lactose (P< 0.001), TDE (P = 0.047), NFDE (P= 0.003) and a higher concentration of milk urea nitrogen (P= 0.001) and casein (P= 0.001), than primiparous buffaloes, which in turn had a higher urine pH value (P< 0.001) than multiparous buffaloes in the pre-calving period. The primiparous animals had a higher concentration of leukocyte (P= 0.001) and lymphocytes (P< 0.001) post-calving and a higher hematocrit concentration (P= 0.004) pre-calving. Buffaloes during the transition period exhibited some variations in the oxidative stress related to their metabolic status. After calving, buffaloes with a high BCS at calving and greater lipid mobilization have a more marked alteration in oxidative status, but improved production performance. There was a positive correlation between the body condition score (ECC) in the second week of lactation and the crude protein levels in the milk (S2 = 0.400 P = 0.038), and total dry stratum (S2 = 0.448, P = 0.019). Primiparous buffaloes during the transition period exhibited negative inter-relationships between metabolic traits and productive performance variations in the oxidative stress related to their metabolic status.