Kilogram Of Live Weight Research Articles

Glucose Tolerance in Ewes and Susceptibility to Pregnancy Toxaemia

Intravenous glucose tolerance tests were undertaken on fed twin-pregnant ewes at about 120 days of gestation by injecting 0.4 g glucose per kilogram of live weight, then measuring glucose and insulin concentrations in plasma over the next 2 h. An insulin resistance index was calculated from the product of T1/2 for glucose disappearance and the plasma insulin concentrations integrated over time. Approximately 10 days later, the ewes were starved to induce ovine pregnancy toxaemia. During this period, the course of the hypoglycaemia and ketonaemia were followed by measuring metabolite concentrations in jugular blood samples obtained every 2-3 days. The existence of dehydration, acid-base imbalance and renal failure was also determined from packed cell volumes, serum CO2 content and serum concentrations of urea, creatinine and inorganic phosphate. Ewes that became recumbent and moribund with the disease were classified as susceptible whereas those asymptomatic after 10 days were classified as non-susceptible. Seven susceptible ewes had significantly higher insulin resistance indices (2043 +/- 670 s.d.) than did six non-susceptible ewes (1261 +/- 433 s.d.). It was concluded that poor control of glucose homeostasis may be an important predisposing factor in pathogenesis of the disease.

Reevaluation of the Minimum Vitamin A Requirement of Holstein Male Calves Based Upon Elevated Cerebrospinal Fluid Pressure

Forty-one male Holstein calves whose average age was 60 days, live weight 74kg and plasma vitamin A concentration 8.4μg/100ml were fed a vitamin A depletion ration plus one of five daily vitamin A acetate intakes equivalent to 4, 12, 16, 64 or 256μg of retinol per kilogram of live weight for 16 weeks. Daily ration consumption averaged 3.0 kg/day, and live weight increased .81kg/day. The incidence of diarrhea, the number of treatments for diarrhea, and the number of calves exhibiting convulsions were greater in the calves fed the lowest vitamin A intake of 4μg. Average plasma vitamin A concentrations increased .8μg/100ml for each 10% increase in vitamin A intake and terminal values increased .9μg/ 100ml. Cisternal cerebrospinal fluid (CSF) pressures were maintained at a geometric mean of 68mm of saline at vitamin A intakes greater than 29μg per kilogram of live weight. For each 10% decrease in vitamin A intake below the 29μg intake, CSF pressure increased by 8.6%.

Bone Growth in the Hypovitaminotic a Calf

Abnormal bone in growing hypovitaminotic A animals has been attributed to altered endochondral growth, faulty appositional growth, and interference with normal resorption and remodeling. In an attempt to resolve these conflicting findings, bone growth was quantitatively estimated in 16 Holstein male calves fed either 8 or 108 μg vitamin A per kilogram of live weight daily for 16 weeks. The deficient animals (8 μg intake) had low plasma vitamin A concentrations, elevated cerebrospinal fluid (CSF) pressures, impaired absorption of CSF, papilledema and squamous metaplasia of the parotid gland ducts. The volumes of the cranial vaults and the brain weights were less in deficient animals, but when the latter criterion was expressed as weight per unit live weight, the difference was not significant. The dura mater in the hypovitaminotic A calves was thicker over the anterior cerebellum, tentorium cerebelli and in the area of the lumbar vertebrae. While total volumes of the vertebrae of the two groups were similar, the deficient animals had smaller spinal canals and smaller ratios of canal to total volume. Metacarpal diaphyseal sections, labelled with tetracycline and 2,4-bis[N,N′-di(carboxymethyl)aminomethyl]fluorescein, of hypovitaminotic A calves had a significantly increased growth rate in the anterior lateral cortex. The vertebrae of deficient animals tended to have less bone and more osteoid. The results are in accord with the hypothesis that in hypovitaminosis A increased osteoblastic activity results in altered bone growth. Osteoclastic activity appeared to be unaffected.

Content of Sodium and Potassium in Supraspinatus Muscle from Hypovitaminotic A Holstein Calves

Twenty-three six-week-old Holstein male calves were fed a vitamin A depletion ration, at levels anticipated to produce a weekly increase in live weight of 5%, supplemented with one of four vitamin A intakes : 4, 12, 36, or 108μg per kilogram of live weight per day for a 16-week period. Live weight gain was slightly less in those calves fed the 4 and 12μg intakes. Plasma vitamin A concentrations essentially reflected intakes of the vitamin, and cerebrospinal fluid pressure was elevated in the calves fed the 4 and 12μg intakes, with the degree of elevation related inversely to the vitamin intake. Dry matter and sodium contents of the supraspinatus muscle were unaffected by vitamin A intake. Slightly lower ash and potassium concentrations were found in the muscle of those calves fed the 4 and 12μg intakes of the vitamin, but when these constituents were expressed on a dry matter basis, there were no apparent effects due to level of vitamin A intake.

Sobre o uso de iodeto de ditiazinina como antihelmíntico. III - Observações sobre sua eficácia na remoção de Moniezia benedini (Moniez, 1879) em caprinos

The authors investigated the efficiency of Ditiazanine Iodide on infestations by Moniezia benedeni (Moniez, 1879) in goats. Employing for such 23 infected goats of which 5 were sacrificed 10 days after the end of the treatment. Of those 4 treated and one untreated. The dose employed was approximately 20,0 mg of Ditiazanine Iodide per Kilogram of live weight and for day, for 5 days, administering the daily dose twice. In this dose the product showed high efficiency, and not determining any indesirable collateral effects. The efficiency was observed by examination of proglottids in the faeces, at the beginning of the treatment or by the date gathered in the necropsy. The toxicity was examined through necroscopies, with a view to encountering anatomo-pathological lesions which could be attributed to the medicament and through blood tests.

Cisternal Cerebrospinal Fluid Pressure during Development of Chronic Bovine Hypervitaminosis A

Twenty male Holstein calves, average age 94±8 days and average plasma vitamin A 11.6±1.2 μg/100ml were fed one of three daily intakes of vitamin A (calculated as retinol), either 55, 8,800, or 26,400 μg per kilogram of live weight, for one of four durations, 3, 6, 12, or 24 days. The trend in cisternal cerebrospinal fluid (CSF) pressures, taken in left lateral recumbency under general anesthesia, with days fed vitamin A, did not differ significantly from zero for those calves fed either the 55- or 8,800-μg intakes. For those fed the 26,400-μg intake, there was a 1.4% decrease in pressure per day for the actual values and a decrease of 1.6% for the age-adjusted values. It is tentatively concluded that CSF pressures are not increased during the early stages of bovine chronic hypervitaminosis A.

The Endogenous Metabolism of Hens and Capons

In view of the scarcity of data in the literature as to the value of various proteins for poultry feeding, experimental work on this phase of the problem was undertaken in this laboratory. It was planned first to study the endogenous nitrogen excretion of birds on a nitrogen-free diet to obtain a figure representative of their excretion in terms of milligrams of nitrogen excreted daily per kilogram of live weight. Preliminary trials with mature birds indicated that this figure would approach a constant value. The chickens were then to be placed on a ration containing a known amount of protein from a certain source and the total nitrogen of their excrement again determined. Then, the difference between the nitrogen excreted when a protein was included in the diet, and when on a nitrogen-free ration, divided by the amount of nitrogen fed per kilogram would be the unutilized portion. When this .