An Observational Analysis of Secondary Sex ratio, Stillbirth and Birth Weight in Iranian Buffaloes (Bubalus bubalis)

Authors
N. Ghavi Hossein-Zadeh 1
M. Madad 1
A. A. Shadparvar 1
D. Kianzad 2
1 Department of Animal Science, Faculty of Agricultural Science, University of Guilan, Rasht, Islamic Republic of Iran.
2 Animal Breeding Center of Iran, P. O. Box 31585-963, Karaj, Islamic Republic of Iran.
Abstract
Calving records of Iranian buffaloes from April 1991 to June 2010 comprising 1,151 herds with 34,911 calving events were used to evaluate reported secondary sex ratio, stillbirth, and calf birth weight. Logistic regression models were applied to analyze stillbirth and calf sex at birth, and statistical analysis of calf birth weight was performed using a linear mixed model. Overall, the ratio of males to females was 53:47. It was observed that there were no significant effects of herd, calving year, season of calving, dam parity or interactions between these effects on the odds of male or female rates in Iranian buffaloes. Greater odds of calf stillbirth existed for calves born from primiparous buffaloes than from multiparous ones (Odds Ratio (OR)= 1.83; P< 0.0001). The greatest odds of stillbirth was for spring season (OR= 2.47; P< 0.0001), and male births had greater odds of stillbirth than female ones in Iranian buffaloes (OR= 1.21; P< 0.01). In general, male calves were heavier than the female calves at birth (P< 0.01) and the birth weights of calves from cows of parity 4 and beyond were significantly more than the weights of calves from cows of other parities (P< 0.01). Fall-born calves had significantly greater body weight at birth than calves born in other seasons (P< 0.01). It seems that providing good management practices for primiparous and multiparous buffaloes to minimize stress before parturition can reduce stillbirth incidence.

Keywords

1. Abdelaziz, M. A., Shalaby, N. A. and Al-Hur, F. S. 2010. Comparison between Genetic Parameters for Birth Weight of Egyptian Buffaloes Estimated by Random Regression and Multi-trait Models. Proceedings of the 9th World Congress on Genetics Applied to Livestock Production, Leipzig,1Germany,1http://www.kongressband.de/wcgalp2010/assets/pdf/0175.pdf
2. Bicalho, R. C., Galvão, K. N., Cheong, S. H., Gilbert, R. O., Warnick, L. D. and Guard, C. L. 2007. Effect of Stillbirths on Dam Survival and Reproduction Performance in Holstein Dairy Cows. J. Dairy Sci., 90: 2797-2803.
3. Bicalho, R. C., Galvão, K. N., Warnick, L. D. and Guard, C. L. 2008. Stillbirth Parturition Reduces Milk Production in Holstein Cows. Prev. Vet. Med., 84: 112-120.
4. Hansen, M., Misztal, I., Lund, M. S., Pedersen, J. and Christensen, L. G. 2004. Undesired Phenotypic and Genetic Trend for Stillbirth in Danish Holsteins. J. Dairy Sci., 87: 1477–1486.
5. Hosmer, D. and Lemeshow, S. 2000. Applied Logistic Regression. 2nd Edition, Wiley-Interscience, John Wiley and Sons, New York, NY, Pp.392.
6. Kianzad, D. 2000. A Case Study on Buffalo Recording and Breeding in Iran. ICAR Tech. Ser., 4: 37-44.
7. Maizon, D. O., Oltenacu, P. A., Gröhn, Y. T., Strawderman, R. L. and Emanuelson, U. 2004. Effects of Diseases on Reproductive Performance in Swedish Red and White Dairy Cattle. Prev. Vet. Med., 66: 113-126.
8. Naqvi, A. N. and Shami, S. A. 1999. Secondary Sex Ratio in Nili-Ravi Buffalo. Pak. J. Biol. Sci., 2(3): 1030-1033.
9. Naserian, A. A. and Saremi, B. 2007. Water Buffalo Industry in Iran. Ital. J. Anim. Sci., 6 (Suppl 2): 1404-1405.
10. Pursley, J. R., Silcox, R. W. and Wiltbank, M. C. 1998. Effect of Time of Artificial Insemination on Pregnancy Rates, Calving Rates, Pregnancy Loss, and Gender Ratio after Synchronization of Ovulation in Lactating Dairy Cows. J. Dairy Sci., 81: 2139-2144.
11. SAS Institute. 2002. User’s Guide: Statistics, Version 9.1 Edition. SAS Inst., Inc., Cary, NC.
12. Sethi, R. K. 2003. Improving Riverine and Swamp Buffaloes through Breeding. Proc. of the Fourth Asian Buffalo Congress, 25 to 28 Feb., New Delhi, India, PP. 51-60.
13. Steinbock, L., Nӓsholm, A., Berglund, B., Johansson, K., and Philipsson, J. 2003. Genetic Effects on Stillbirth and Calving Difficulty in Swedish Holsteins at First and Second Calving. J. Dairy Sci., 86: 2228–2235.
14. Tavakolian, J. 2000. An Introduction to Genetic Resources of Native Farm Animals. Anim. Sci. Res. Inst., Karaj. Iran, Pp.451
15. Trivers, R. L. and Willard, D. 1973. Natural Selection of Parental Ability to Vary the Sex Ratio of Offspring. Sci., 179: 90 –92.
16. Usmani, R. H., Lewis, G. S., and Naz, N. A. 1987. Factors Affecting Length of Gestation and Birth Seight of Nili-Ravi Buffaloes. Anim. Reprod. Sci., 14(3): 195-203.
17. Visscher, D. R., van Aarde, R. J., and Whyte, I. 2004. Environmental and Maternal Correlates of Foetal Sex Ratios in the African Buffalo (Syncerus caffer) and Savanna Elephant (Loxodonta africana). J. Zool., Lond., 264: 111–116.
Journal of Agricultural Science and Technology
Volume 14, Issue 7
November and December 2012
Pages 1477-1484