Screening to Prevent to Carential and Metabolic Disease and HPTNS of Equids Grazing Forage Grasses with Unbalanced Levels of Minerals, Through the Mineral Profile and Creatinine Clearance Ratio for Ca and P Assessment

Abstract

In the present study, 229 horses were evaluated, belonging to 76 properties, 25 Municipalities of the Center-Western region of São Paulo State, covered for a period of clinical observations from 1984 to 2010. Were performed sampling grazing elephant grass and various supplements for dosages minerals, being macro and microminerals and oxalate content in dry matter (DM) of Brachiaria humidicola and elephant grass (Pennisetum purpureum). The equids of farms with a history of skeletal or osteoarticular problems were evaluated for Calcium (Ca), Phosphorus (P) and Creatinine (Cr) in urine and serum to determine the percentage of Cr depuration for the Ca and P (%DRCr-Ca and P). The clinical observations of osteopathies were determined. The main lesions found in animals after death were evaluated. The analysis leaf mineral of B. humidicola presented values ranging from 2.40 g Ca to 3.68 g Ca/kg DM and 0.40 g P to 0.74 g P/kg DM. The high toxic levels of oxalate ranged from 1.15-3.10% oxalic acid in DM of B. humidicola and 4% in DM of elephant grass. The higher Ca/Oxalate ratio was 0.37 (B. humidicola) and the lower of 0.08 (P. purpureum). The largest amounts were excreted 58 mg of Ca and P 47.50 mg/dL in the urine and the lowest was 4 mg Ca and 3.50 mg P/dL of urine. The clearance of ratio, ranged from 0.63-6.28% (μ = 2.48; sd ± 1.28; cv = 51.61%) for %DR- Ca, while the %DR- P ranged from 1.23-35.92% (μ = 17.33; sd ± 8.35; cv = 48.15%). 50% of values of %DRCr-Ca and 95% of values of %DRCr-P were considered abnormal, thus predisposing to osteopathy and renal dysfunction as glomerulonephritis and nephritis. Above of 50% of the animals of properties, presented one or more types of skeletal tissue disease, affecting bones flat (osteochondrosis) or long bone (epiphysitis). Young animals showed accelerated growth in bone problems of members. Animals at play and hard work showed symptoms of nutritional secondary Hyperparathyroidism (HPTNS) when presenting the fibrous osteodystrophy ("swollen face disease") in addition to problems with the locomotor apparatus and in general with the skeletal system. The diagnosis in a timely manner the problem of imbalance in the diet using the technique of %DRCr-Ca and P possible prevention of osteopathies, those reversible. The change of grazing animals to forage less oxalic acid content (<0.50%) and appropriate supplementation prevented the problem, except frames and pathophysiology of chronic glomerulonephritis due to HPTNS. Young animals in accelerated growth showed bone problems of members. Animals in reproduction and hard work showed symptoms of HPTNS, presented signs of fibrous osteodystrophy, besides problems with the locomotor system and in general with the skeletal system. The diagnosis in time habile of the problem of imbalance of diet through of the assessment of %DRCr- Ca and P, enabled prevent the osteopathies, those reversible. The change of the animals to pasture with forages of minor oxalic acid content (<0.50%) and receiving adequate supplementation prevented the problem, except frames chronic pathophysiological of HPTNS and glomerulonephritis.