Effect of environmental physiological and managemental parameters at insemination on conception rate of exotic (European) indigenous cows
Date
2000-12-16
Authors
Perera, E. R. K.
Udayanga, H. N. R.
Jayaweera, N.
Perera, A. N. F.
Journal Title
Journal ISSN
Volume Title
Publisher
University of Peradeniya
Abstract
One hundred and one Exotic (European) * Indigenous crossbred cows presented for artificial insemination (AI) at Pannala Veterinary Range from April to July. 2000 were used to examine the effect. of environmental temperature (ET). various physiological parameters of the cows. and management factors at the time of insemination. on conception rate (CR) of Exotic (European) * Indigenous crossbred cows in Sri Lanka.
Data on breed. age. parity, date of last calving, average daily milk yield and interval from detection of heat to insemination (IDI) of each cow were recorded based on the information provided by the owner. Environmental temperature (ET), vaginal temperature (VT). rectal temperature (RT). pulse rate (PR), respiration rate (RR), length and width of vulva, and body condition score (BCS) of individual cows at the time of insemination were measured. Heat signs (HS) of each cow at the time of insemination were assessed by adopting a scoring system, which assigned a score for each heat symptom examined. based on its intensity of expression, Two experienced technicians performed all 101 inseminations. Time of insemination and inseminator number were recorded for each insemination. Per rectal pregnancy diagnosis was performed at 75 days after insemination. Data were subjected to correlation and regression analysis. and analysis of variance procedures.
Mean ET at the time of insemination was 31.2 ± 1.5 "C. resembling the typical daytime temperature conditions prevailing during these months in the intermediate zone of Sri Lanka. Mean age, parity, days postpartum (OPP) and BCS of cows were 5.39 ±2.74 yr, 2.52 ±1.55, 213±115 d and 2.7-1-± 0.65, respectively. These values suggest that the cows included in the study were a representative sample of the normal population of breedable cows. Mean PRo RR. VT and RT of 101 cows at the time of insemination were 68.-1-±2.4 beats/min. 24.6 ±1.5 breaths/min. 39.-1-5±0.38 °C and 38.5 ±0.4 °C, respectively. The values of physiological parameters were within the nonnal range for cattle. Relationships between ET at the time of insemination. and individual PRo RR, RT, and VT were positive. indicating increase in body temperature at higher ET despite induced thermoregulatory responses. Mean VT was 0.9 ± 0.1 ° C higher than mean RT in cows. and VT and RT were positively correlated (r = 0.58. p<0.05). Conception rate (65.-1-±1.2 %) was not significantly different between the two technicians. CR was highest in cows with BCS of 2 to 3, parity of 2 to 3. between 61 and 150 DPP. and when ID! was <13 hr. Inseminations performed after 19 hr lapse from detection of heat were not successful. CR declined (p < 0.05) by 8%,3.9"10. 5.2% and 4.9% with every 1°C, O.I°C. D.l°C and 1 hr increase in ET, RT. VT. at the time of insemination. and delay in time from detection of heat to insemination. respectively, CR was lowest when ET. RT. VT, and IDI at insemination were above 31.7 °C. 38.6 "C. 39.6 "C. and 19 hr. Highest CR resulted from inseminations performed whenET. RT. VT. and IDI at insemination were below 30.9 "C. 38.2 °C, 39.3 "C. and 13 hr. respectively. These trends are in the same direction. but the values are different to those reported for Holstein cows.
The results suggest that CR in Exotic (European) * Indigenous cross bred cows in the sample was affected by ET. RT. yr. BCS. parity. DPP and IDI. Highest CR was resulted from inseminating cows having BCS of 2·3. parity of 3. between 61 to 150 DPP. within 13 hours of detection of heat. and when ET. RT. VI' were below 30.9 "C, 38.2 "C, and 39.3 "C. respectively.
Description
Keywords
Animal , Science Managemental parameters Cows
Citation
Proceedings and Abstract of the Annual Research Sessions, December 16, 2000, University of Peradeniya, Sri Lanka pp 15-26