Studies on the Endocrine and Environmental Factors Influencing Post Partum Acyclicity in Dairy Cows Based on Progesterone Profiles (Preliminary Results)

An Analysis of Ovarian Dysfunction in High Yielding Dairy Cows After Calving Based on Progesterone Profiles

“…The results however show a large standarddeviation, suggesting that a lot of factors influence ovarian resumption and illustrating the need for further epidemiological investigation into what factors that might be. In earlier studies carried out some 10 to 20 years ago, the occurrence of the first progesterone rise after calving was stated to occur on the average between 20 to 30 days after calving (Bulman and Lamming, 1978;Caudle et al, 1982;Fonseca et al, 1983;Henriksen and Jensen, 1985;Fagan and Roche, 1986). Also these authors mentioned rather large standarddeviations, which stimulated some of them to look for possible risk factors for delayed ovarian activity.…”

“…As possible risk factors were recognized: the season of calving (cows calving in the spring significantly resume ovarian activity later than cows calving in autumn) (Claus et al, 1983); the housing system (cows in stanchion barns significantly resume ovarian activity later than cows in loose housing systems) (Kozicki, 1982); the parity (first calving cows resume ovarian activity later than multiparous cows) (Bulman and Lamming, 1978;Bostedt et al, 1985); and the occurrence of puerperal disturbances (Callahan et al, 1971;Fonseca et al, 1983). Although the importance of these delaying factors was generally accepted, authors came to the conclusion that 90 to 95% of the dairy cows resume ovarian activity by day 50 after calving (Bulman and Lamming, 1978;Bulman and Wood, 1980;Henriksen and Jensen, 1985). This led to the overall conclusion that the failure to detect oestrus symptoms was a more important cause of a prolonged interval to first insemination than delayed ovulations.…”

“…In studies based on post partum progesterone profiles, it has been demonstrated that 90 to 95% of the post partum dairy cows have resumed ovarian cycles by day SO after calving (Bulman and Lamming, 1978;Bulman and Wood, 1980;Henriksen and Jensen, 1985). Hence, a 'normal' post partum dairy cow has been defined as one which has resumed ovarian cyclicity by day 50 post partum and continues cycling at regular intervals of approximately 2 1 days (Lamming, Wathes and Peters, 1981).…”

Some Metabolic Characteristics of Dairy Cows with Different Post Partum Ovarian Function

“…However, there is only a limited number of reports in which both metabolic and ovarian functions were monitored by exact laboratory and clinical methods (BERGLUND and LARSSON, 1983;REID et al, 1983;WATSON and HARWOOD, 1984;ELDON et al, 1985;HARASZTI et aI., 1985;WATSON, 1985). In a previous trial performed in Hungarian large-scale dairy farms a higher rate of post partum ovarian dysfunction with a more distinct effect on re-conception was verified (HUSZENICZA et al, 1987) than was found in conventional family farms in Western Europe (BALL, 1982;CLAUS et aI., 1983;HENRIKSEN and JENSEN, 1985). The unlikely occurrence of subclinical abnormalities in energy metabolism being due to feeding difficulties in large herds may be assumed as a possible cause of the above mentioned contradictions (HUSZEN1CZA et al, 1988), but there are no data available about metabolic characteristics of cows with different post partum ovarian disturbances.…”

Postpartum Adrenal, Pituitary and Ovarian Functions in Dairy Cows

“…Dairy cows are exposed to considerable stress during the early postpartum period. Parturition (HUDSON et al, 1975), onset and peak of lactation (BUTLER et al, 1981; GwAZ-DAUSKAS et al, 1986), negative energy balance (COPPOCK et aI., 1974;BUTLER er al., 1981;BUTLER and SMITH, 1989;CANFIELD and BUTLER, 1991), loss of body condition (DUCKER et al, 1985;HENRIKSEN and JENSEN, 1985;HEINONEN et al, 1988) and periparturient disorders (STUDER and MORROW, 1978;ERB and SMITH, 1987;STEVENSON and CALL, 1988;NAKAO et al, 1992) usually occur within a relatively short period of time.…”