Bulletin of the Szent István University 2007 [antikvár]

FREQUENCY AND PATHOGENESIS OF LUTEAL CAVITIES AND CYSTS IN DAIRY CATTLEBALOGH O.', SÁNDOR CS.^, LUKÁCSI E.^, GÁBOR GY', MÉZES M.^ 'Department of Cattle Breeding, Research Institute for Animal Breeding and Nutrition, H-2053 Herceghalom, Hungary ^Bácsalmás Agro-industrial Co. Ltd., Bácsalmás, Hungary ^Androvet Ltd., Budapest, Hungary^Department of Nutrition, Szent István University, Gödöllő, Hungary KEYWORDS: corpus luteum, luteal cavity, luteal cyst, dairy cattleABSTRACTImprovement of the average milk production of dairy cattle populations kept in intensive production systems caused simultaneously a dramatic decrease in their reproductive performance. The possible solution of these anomalies had been investigated by several research teams and different theories about it were mentioned. After ovulation the theca interna and the granulosa cells of the follicle undergo a dramatic transformation known as luteinization. Luteolysis means désintégration or decomposition of the corpus luteum. It occurs during one to three day period at the end of the luteal phase. The initial phase of the regression of corpus luteum seems to be similar to an inflammatory reaction but not followed by necrosis, but luteal cell-apoptosis.Our research group carried out more than 8 thousands ultrasonographic examinations in dairy cows between January 2003 and December 2006. Uterus and both ovaries were checked during rectal examinations. There were found dfferent lutein forms, such as normal corpus luteum (CL), CL with cavity and lutein cysts. Surprisingly among the investigated animals 2.3% CL with cavity were found in pregnant cows, 9.7% CL with cavity were found in open cows and 19.3% of open cows had at least one lutein cyst on their ovaries. That means totally 28.9% irregular lutein forms in these cows. The possible cause of those irregular CL formation discussed.INTRODUCTIONIn the last decades a continuous elevation of the average milk production was recorded of all dairy cattle populations kept in intensive production systems. In the other hand simultaneously a dramatic decrease appeared in their reproductive performance what