Perfil hidroeletrolítico, ácido-base, metabólico e mineral de vacas da raça holandesa no pós-parto e avaliação da fluidoterapia oral

Abstract

Transition dairy cows have a higher risk of metabolic and infectious diseases. The aim of this study was to characterize the electrolyte, acid-base, metabolic and mineral profiles, and assess the influence of oral drenching of a polyionic solution within the first 24 hours postpartum in Holstein cows. In experiment I, were obtained reference values immediately after calving of 24 cows. Then we evaluated the behavior of the variables in the first 24 hours postpartum in a group composed of eight primiparous cows and another eight pluriparous. In experiment II, 16 pluriparous fresh cows were used. They were randomly divided into two groups of eight subjects each. One group remained as controls while another group was drenched with 30L of water plus 200g MgSO4, 100g CaCl2, 100 g KCl and 300 mL propylene glycol, two hours after calving. In both experiments blood samples were taken at the following times: calving, 2h, 4h, 6h, 12h and 24 hours postpartum. At each sampling time, was carried blood gas analysis with the aid of a portable clinical analyzer, dosages of AST, GGT, total bilirubin, LDH, ALP, total plasma protein, creatinine, NEFA, HB, Ca + +, Mg + + and PO4-. At calving time, the cows had electrolytes e blood gas analysis profile within the reference ranges for the species. The mean concentrations of glucose (108 mg/dL), Ca (11 mg/dL) and Mg (3.1 mg / dL) were high, while the total plasma protein (6.5 g/dL) was below the lower limit for this variable. At 24 hours postpartum, the pluriparous showed greater (p <0.05) LDH (1511 U/L) and AST (97 U/L) activity, and higher concentrations of HB (1.067 mmol/L) than primiparous, demonstrating increased liver function and more intense negative energy balance in this group. In that moment,the pluriparous also had hypochloremic metabolic alkalosis, with lower chloride levels (p<0.05) than primiparous, beyond high blood pH (7.47). The postpartum oral drenching was efficient in maintaining the electrolyte and acid-base balance, improved renal perfusion and blood volume, and reduced the negative energy balance, characterized by lower concentrations of urea (29 mg/dL), creatinine (0.9 mg/dL), HB (0.703 mmol/L), and decreased activity of AST (58 U/L) and LDH (822 U/L) in the treated group. It can be concluded that fresh dairy cows showed mild dehydration, hypochloremic metabolic alkalosis and negative energybalance. The postpartum oral drenching was an auxiliary tool in maintaining electrolyte and acid-base balance, and energy metabolism during this period.