Predicting optimal time of insemination in cows that show visual signs of estrus by estimating onset of estrus with pedometers.

An experiment was designed to estimate the optimal interval from the beginning of estrus to artificial insemination (AI). The data were analyzed by means of a mathematical model. The analysis was based on pedometer readings and results of rectal palpation at 42 to 49 d post-AI of 171 breedings in 121 cows. The chance of conception was highest between 6 and 17 h after increased pedometer activity; the estimated optimum was at 11.8 h. In this data file, the effects of disease, inseminator, time of AI (a.m. or p.m.), and bull did not contribute to the improvement of the model. The effects of disease were not significant because of the low incidence of any specific disease. Activity measurements can be used as a tool for AI strategy to improve conception in groups of healthy cows and heifers already showing visual signs of estrus.

[1]  W. Buist,et al.  Inference for threshold models with variance components from the generalized linear mixed model perspective , 1995, Genetics Selection Evolution.

[2]  D. Schams,et al.  The oestrous cycle of the cow: hormonal parameters and time relationships concerning oestrus, ovulation, and electrical resistance of the vaginal mucus. , 1977, Acta endocrinologica.

[3]  W. Mccaughey,et al.  Tail painting technique as an aid to oestrus detection in cattle , 1984, The Veterinary Record.

[4]  Gregory S. Lewis,et al.  Oestrus detection in cattle: recent developments , 1992 .

[5]  David R. Cox.  The analysis of binary data , 1970 .

[6]  A. Keen,et al.  A simple approach for the analysis of generalizea linear mixed models , 1994 .

[7]  I. Politis,et al.  Effects of Staphylococcus aureus toxins on the growth of bovine mammary epithelial cells (MAC-T) in culture. , 1995, Journal of dairy science.

[8]  E. Peeler,et al.  The scope for raising margins in dairy herds by improving fertility and health. , 1993, The British veterinary journal.

[9]  R. Foote.  Time of Artificial Insemination and Fertility in Dairy Cattle , 1979 .

[10]  K. Macmillan,et al.  Fertility differences between groups of sires relative to the stage of oestrus at the time of insemination , 1975 .

[11]  Y. Gröhn,et al.  The association between cumulative milk yield, days open, and days to first breeding in New York Holstein cows. , 1996, Journal of dairy science.

[12]  P S Kalra,et al.  Transitory changes in plasma progestins, estradiol, and luteinizing hormone approaching ovulation in the bovine. , 1975, Journal of dairy science.

[13]  W. E. Vinson,et al.  Rates of conception by artificial insemination of dairy cattle. , 1981, Journal of dairy science.

[14]  W. Holtz,et al.  Die Brunstdiagnose beim Rind , 1993 .

[15]  W. Buist,et al.  Analysis of a Generalized Linear Mixed Model: A Case Study and Simulation Results , 1996 .

[16]  J. Lewis,et al.  Probit Analysis (3rd ed). , 1972 .

[17]  J. Stevenson,et al.  Gonadotropin-releasing hormone and conception of Holsteins. , 1984, Journal of dairy science.

[18]  E. J. Stone,et al.  Estrus, Estrous Cycles, Ovulation Time, Time of Service, and Fertility of Dairy Cattle in Louisiana , 1959 .

[19]  P. L. Senger,et al.  The estrus detection problem: new concepts, technologies, and possibilities. , 1994, Journal of dairy science.

[20]  J. F. Hurnik,et al.  Estrous and related behaviour in postpartum Holstein cows , 1975 .

[21]  B. Brackett,et al.  Fertilization and early development of cow ova. , 1980, Biology of reproduction.

[22]  R L Nebel,et al.  Measuring efficiency and accuracy of detection of estrus. , 1994, Journal of dairy science.

[23]  D. Cox,et al.  Analysis of Binary Data (2nd ed.). , 1990 .

[24]  H. B. Puckett,et al.  Electrical conductivity of reproductive tissue for detection of estrus in dairy cows. , 1989, Journal of dairy science.

[25]  P. Broadbent,et al.  Changes in the composition of cervical mucus of the cow during the estrous cycle as parameters for predicting potential fertility. , 1993, Theriogenology.

[26]  L. Guilbault,et al.  Synchronization of estrus and fertility in beef cattle with two injections of buserelin and prostaglandin. , 1992, Theriogenology.