Calcinosis in goats

Enzootic calcinosis in ruminants: A review

Enzootic calcinosis (EC), is a chronic disease, caused by toxic plants, which has mainly affected ruminants for more than 100 years. It is characterized by a soft tissue calcification, hypercalcemia, hyperphosphatemia, hypoparathiroidism, hypercalcitoninism, osteonecrosis, and osteopetrosis. The toxic compound reported in some of these plants are 1,25(OH)₂D₃ glycosides. Characterization of calcinogenic principles were performed with Solanum glaucophyllum, Trisetum flavescens, Cestrum diurnum, and Stenotaphrum secundatum. Other plant species involved in EC are: Nierembergia rivularis, Nierembergia veitchii, Solanum torvum, and Solanum stuckertii. Clinical and pathological findings are well characterized. We present different aspects of the pathogenic mechanism of EC, including genetic modulation, expression of bone proteins, cellular de-differentiation of arterial smooth muscle cells, phenotypic changes, production of a calcifiable matrix, and modulation of the calcium and phosphorus balance. The use of comparative pathology can bring significant advances in the understanding of the pathogenic mechanism. In this review we present a broad approach to the different aspects of intoxication: history of EC on different continents; plant species, distribution and morphology; toxic principle; pathogenesis; epidemiology; clinical signs; diagnosis; and control and prophylaxis.

Calcinosis--calcinogenic plants

The calcinogenic plants are among the most noxious plants to animals in the world. The pathological and biochemical effects of calcinogenic plants in cattle, sheep, goats, pigs, horses, buffalo and laboratory animals have been determined. The chemical nature of the toxic agents and the precise mechanism by with the calcinogenic plants induces calcinosis have been defined. Most of the active principle present as steroidal glycoside is hydrolyzed in intestine, rumen and other tissues or by the bacterial flora releasing the steroidal fragment, in most cases 1,25(OH)(2)D(3). The excess of vitamin D stimulates CaBP synthesis and calcium and phosphate absorption, producing hypercalcemia and/or hyperphosphatemia. The excessively absorbed mineral cannot be physiologically accommodated, and the deposition in soft tissues results in calcinosis. The different means of treatment of calcinosis and control of calcinogenic plants are discussed with regards to their effectiveness. A number of potential uses of calcinogenic plants have been suggested but none has been exploited on a large scale. The understanding of the mechanisms involved with calcinosis contributed enormously to the compression of vitamin D mechanism. Research methods were developed and improved but a lot is to be done in this fascinating subject.

Arteriosclerosis and related lesions in rabbits

Eleven female rabbits, mainly of the NZW breed, aged between 1 and 3.5 years, were examined post mortem. All had originated over the years 1982 to 1987 from the same rabbitry where they had been fed on pellets from the same manufacturer. Apart from one rabbit, all had a history of progressive loss of bodily condition and six of them had also been infertile. Grossly, most of them were emaciated and their arteries were hardened. In some, hepatopathy, nephropathy and pulmonary emphysema were evident. In one case, mummified foetuses were recovered from the abdominal cavity. Microscopically, degenerative changes and calcification were found in the walls of arteries, kidneys, lungs, hearts and ovaries.