Relación entre el metabolismo energético, elequilibrio ácido-base y el estado productivo de la oveja de raza Gallega

Abstract

THE RELATIONSHIP BETWEEN METABOLIC PARAMETERS (SERUMGLUCOSE,UREA, NONSTERIFIED FATTYACIDSANDTRIGLYCERIDES), AND ACID-BASE BALANCE (VENOUS AND URINARY PH, PO2, PCO2, HCO3 - AND BE) WERE STUDIED IN GALLEGA-BREED EWES. THREE REPRODUCTIVE STAGES: ANOESTRUS, LATE-PREGNANCY AND LACTATION WERE CONSIDERED. VARIATIONS OF THESE PARAMETERS IN EACH PERIOD DEPENDING ON THE EFFECT OF SINGLE OR TWIN PREGNANCY WERE ALSO STUDIED. RESULTS SHOWED THAT THE METABOLISM CHANGED DUE TO THE REQUIREMENTS THAT CHARACTERIZED EACH PERIOD WITHOUT INFLUENCING THE VENOUS PH, ALTHOUGH THERE WERE MODIFICATIONS ON COMPENSATORY MECHANISMS. CLOSE TO THE END OF THE PREGNANCY THERE WAS A LIPID MOBILIZATION TO OBTAIN ENERGY; THIS FACT IMPLIED THE PRODUCTION OF ORGANIC ACIDS WHICH WERE NEUTRALIZED BY BUFFERS, THE RESPIRATORY SYSTEM AND THE KIDNEY. THERE WAS NO INFLUENCE ON THE NUMBER OF FETUSES THAT FEMALE CARRIED. DURING LACTATION THE SITUATION CHANGED AS THE METABOLIC DEMANDS FOR MILK PRODUCTION WERE LOW IN THIS BREED, ALTHOUGH MATERNAL METABOLISM NEEDED MOBILISATION FAT TO OBTAIN ENERGY. AT THIS STAGE, EWES WITH TWO LAMBS PRODUCED MORE MILK, WITH LOWER BUFFER CONCENTRATION IN BLOOD, AND MORE INTENSIVE RESPIRATORY COMPENSATION THAN EWES WITH ONLY ONE LAMB.