Department of Theriogenology, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt
Receive Date: 24 October 2011,
Revise Date: 28 January 2012,
Accept Date: 04 February 2012
The pregnancy results of 17337 inseminations carried out in a dairy herd near Cairo over a period of 12 years were retrospectively analyzed in relation to environmental temperature and temperature-humidity index (THI). The overall average of pregnancy rates to all inseminations was significantly (P<0.01) lower in pluriparous cows (31.0%) than in heifers (63.5%). Stress of lactation, propensity for clinical and subclinical mastitis and problems associated with calving are possible underlying causes. In cows, the month of insemination significantly (P<0.05) influenced the pregnancy rate. A substantial decrease of pregnancy rates from 34.1% in May to 15.7% in July as the maximum environmental temperature increased from 33.3 ˚C to 36.3 ˚C and mean THI increased from 69 to 74 was recorded. In spite of the slight increase in pregnancy rates after July, it remained low during autumn referring to the carryover effects of the summer heat load. This resulted in significantly (P<0.05) lower pregnancy rates during summer (21.2%) and autumn (24.4%) than in winter (39.1%) and spring (37.2%). Maximum environmental temperature and mean THI accounted for 72% and 82%, respectively, of the variations in pregnancy rates. The average number of inseminations per conception was the lowest between January and April (2.4±0.2 to 2.6±0.2). This was followed by a significant (P<0.05) increase in this parameter (from 2.9±0.6 in May to 6.4±1.9 in July) coinciding with increased maximum environmental temperature to reach its peak in July. The overall average number of inseminations per conception in cows was 3.2±0.4. In heifers, the pregnancy rate was high (56.9 to 69.8%) throughout the year with no significant differences between months or seasons of insemination. Better efficiency of heifers at thermoregulation compared with pluriparous cows may be implicated. The average number of inseminations per conception in heifers was 1.6±0.04.
Abdel-Bary H.H., Mahmoud M.M., Zaky H.I. and Mohamed A.A. (1992). Effect of season and month of calving on estrus performance, services per conception and mild yield of Friesian cows in Egypt. Egypt. J. Anim. Prod. 29, 229-253. Afifi E.A., Khalil M.H. and Salem M.A. (1992).Evaluation of imported and locally born Friesian cows raised in commercial farms in Egypt. 1. Models and non genetic effects. Egypt. J. Anim. Prod. 29, 17-41. Alnimer M., DeRosa G., Grasso F., Napolitana F. and Bordi A. (2002). Effect of climate on the response to three estrus synchronization techniques in lactating dairy cows. Anim. Reprod. Sci. 71, 157-168. Armstrong D.V. (1994). Heat stress interaction with shade and cooling. J. Dairy Sci. 77, 2044-2050. Badinga L., Collier R.J., Thatcher W.W. and Wilcox C.J. (1985). Effect of climatic and management factors on conception rate of dairy cattle in subtropical environment. J. Dairy Sci. 68, 78-85. Berman A., Folman Y., Kaim M., Mamen M., Herz Z., Wolfenson D., Ariel A. and Graber Y. (1985). Upper critical temperature and forced ventilation effects for high yielding dairy cows in a subtropical climate. J. Dairy Sci. 68, 1488-1495. Bianca W. (1968). Thermoregulation. Pp. 117-142. in Adaptation of Domestic Animals. E.S.E. Hafez, Ed., Lea and Febiger, Philadelphia. Branton C., Johnston J.E. and Miller G.D. (1953). Physiological and hereditary responses of lactating Holstein-Friesian and Jersey cows to natural environmental temperature and humidity. J. Dairy Sci. 36, 585-389. Cavestany D., El-Wishy A.B. and Foote R.H. (1985). Effect of season and high environmental temperature on fertility of Holstein cattle. J. Dairy Sci. 68, 1471-1478. Chebel R.C., Santos J.E.P., Reynolds J.P., Cerri R.L.A., Juchem S.O. and Overton M. (2004). Factors affecting conception rate after artificial insemination and pregnancy loss in lactating dairy cows. Anim. Reprod. Sci. 84, 239-255. De Rensis F. and Scaramuzzi R.J. (2003). Heat stress and seasonal effects on reproduction in the dairy cow- a review. Theriogenology. 60, 1139-1151. Dunlap S.E. and Vincent C.K. (1971). Influence of postbreeding thermal stress on conception rate in beef cattle. J. Anim. Sci. 32, 1216-1218. El-Itriby A.A. and Asker A.A. (1958). Some production characteristics of native cows, Friesian, Shorthorn and their crosses in Egypt. Emp. J. Expt. Agric. 26, 314-322. El-Itriby A.A., Fahmy S.K. and Barrada M.S. (1963). The Jersy and their crosses in Southern Egypt. Pp. 475- 483. Proc. 2nd Anim. Prod. Conf., Cairo Vol. II. El-Keraby F. and Aboul-Ela A.B. (1982). A study of some non-genetic factors affecting post-partum reproductive performance in Holstein Friesian cows. Trop. Anim. Prod. 7, 329-337. Fair T. (2010). Mammalian oocyte development: checkpoints for competence. Reprod. Fertil. Dev. 22, 13-20. Ferreira R.M., Ayres H., Chiaratti M.R., Ferraz M.L., Araujo A.B., Rodrigues C.A., Watanabe Y.F., Vireque A.A., Joaquim D.C., Smith L.C., Meirelles F.V. and Baruselli P.S. (2011). The low fertility of repeat breeder cows during summer heat stress is related to a low oocyte competence to develop into blastocysts. J. Dairy Sci. 94, 2838-2392. Flamenbaum I., Wolfenson D., Mamen M. and Berman A. (1986). Cooling dairy cattle by a combination of sprinkling and forced ventilation and its implementation in the shelter system. J. Dairy Sci. 69, 3140-3147. Folman Y., Berman A., Herz Z., Kaim M., Rosenberg M., Amen M. and Gordin S. (1979). Milk yield and fertility of high yielding dairy cows in a subtropical climate during summer and winter. J. Dairy Res. 46, 411-425. Galina C.S. and Arthur G.H. (1989a). Review of cattle reproduction in the tropics. Part1. Puberty and age at first calving. Anim. Breed. Abstr. 57, 583-590. Galina C.S. and Arthur G.H. (1989b). Review of cattle reproduction in the tropics. Part 2. Parturition and calving intervals. Anim. Breed. Abstr. 57, 679-686. Galina C.S. and Arthur G.H. (1989c). Review of cattle reproduction in the tropics. Part 3. Puerperium. Anim. Breed. Abstr. 57, 899-909. Galina C.S. and Arthur G.H. (1990a). Review of cattle reproduction in the tropics. Part 4. Estrous cycles. Anim. Breed. Abstr. 58, 697-707. Galina C.S. and Arthur G.H. (1990b). Review of cattle reproduction in the tropics. Part 5. Fertilization and pregnancy. Anim. Breed. Abstr. 58, 805-813. Garcia-Ispierto I., Lopez-Gatius F., Bech-Sabat G., Santolaria P., Yaniz J.L., Nogareda C., DeRensis F. and Lopez-Bejar M. (2007). Climatic factors affecting conception rate of high producing dairy cows in northeastern Spain. Theriogenology. 67, 1379-1385. Grohn Y.T. and Rajala-Schultz P.J. (2000). Epidemiology of reproductive performance in dairy cows. Anim. Reprod. Sci. 60, 605-614. Gwazdauskas F.C., Lineweaver J.A. and Vinson W.E. (1981). Rates of conception by artificial insemination of dairy cattle. J. Diary Sci. 64, 358-362. Gwazdauskas F.C., Thatcher W.W. and Wilcox C.J. (1973). Physiological, environmental and hormonal factors at insemination which may affect conception. J. Dairy Sci. 56, 873-877. Huang C., Tsuruta S., Bertrand J.K., Misztal I., Lawlor T.J. and Clay J.S. (2008). Environmental effects on conception rates of Holsteins and NewYork and Georgia. J. Dairy. Sci. 91, 818-825. Ingraham R.H., Gillette D.D. and Wagner W.D. (1974). Relationship of temperature and humidity to conception rate of Holstein cows in subtropical climate. J. Dairy Sci. 57, 476-481. Kadzere C.T., Murphy M.R., Silanikove N. and Maltz E. (2002). Heat stress in lactating dairy cows: a review. Livest. Prod. Sci. 77, 59-91. Khishin S.S. and El-Issawi H.F. (1954). The Jersey in Egypt. Emp. J. Expt. Agric. 22, 121-127. Kuhn M.T. and Hutchison J.L. (2005). Factors affecting heifer fertility in US Holsteins. J. Dairy Sci. 88, 11-15. Leroy J.L.M.R., Opsomer G., De Vliegher S., Vanholder T., Goossens L., Geldhof A., Bols P.E.J., De Kruif A. and Van Soom A. (2005). Comparison of embryo quality in high- yielding dairy cows, in dairy heifers and in beef cows. Theriogenology. 64, 2022-2036. Lopez-Gatius F. (2003). Is fertility declining in dairy cattle? A retrospective study in northeastern Spain. Theriogenology. 60, 89-99. Lopez-Gatius F., Lopez Bejar M., Fenech M. and Hunter R.H.F. (2005). Ovulation failure and double ovulation in dairy cattle: risk factors and effects. Theriogenology. 63, 1298-1307. McGowan M.R., Mayer D.G., Tranter W., Shaw M.S., Smith C. and Davison T.M. (1996). Relationship between temperature humidity index on conception efficiency of dairy cattle in Queensland. Proc. Aust. Soc. Anim. Prod. 21, 454-457. Morton J.M., Tranter W.P., Mayer D.G. and Jonsson N.N. (2007). Effects of environmental heat on conception rates in lactating dairy cows: critical periods of exposure. J. Dairy Sci. 90, 2271-2278. Nagamine Y. and Sasaki O. (2008). Effect of environmental factors on fertility of Holstein-Friesian cattle in Japan. Livest. Sci. 115, 89-93. NRC. (2001). Nutrient Requirement od Dairy Cattle, 7th Rev. Ed. Washington Academy Press, Washington, D.C. Orr W.N., Cowan R.T. and Davison T.M. (1993). Factors affecting pregnancy rate in Holstein Friesian cattle mated during summer in a subtropical environment. Aust. Vet. J. 70, 251-256. Pursley J.R., Wiltbank M.C., Stevenson J.S., Ottobre J.S., Garverick H.A. and Anderson L.L. (1997). Pregnancy rates per artificial insemination for cows and heifers inseminated at a synchronized ovulations synchronized estrus. J. Dairy Sci. 80, 295-300. Ragab M.T. and Asker A.A. (1959). Some economic characteristics of the Friesian cattle in the Tahreer province. Ann. Agric. Sci. 4, 104-107. Rizos D., Carter F., Besenfelder U., Havlicek V. and Lonergan P. (2010). Contribution of the female reproductive tract to low fertility in postpartum lactating dairy cows. J. Dairy Sci. 93, 1022-1029. Ron M., Bar-Anan R. and Wiggans G.R. (1984). Factors affecting conception rate of Israeli Holstein cattle. J. Dairy Sci. 67, 854-860. Roth Z., Arav A., Bor A., Zeron Y., Braw-Tal R. and Wolfenson D. (2001). Improvement of quality of oocytes collected in the autumn by enhanced removal of impaired follicles from previously heat-stressed cows. Reproduction. 122, 737-744. Santos J.E.P., Cerri R.L.A., Ballou M.A., Higginbotham G.E. and Kirk J.H. (2004). Effect of timing of first clinical mastitis occurrence on lactational and reproductive performance of Holstein dairy cows. Anim. Reprod. Sci. 80, 31-45. Sartori R., Bastos M.R. and Wiltbank M.C. (2010). Factors affecting fertilization and early embryo quality in single and superovulated dairy cattle. Reprod. Fertil. Dev. 22, 151-158. Sartori R., Sartat-Bergfelt R., Mertens S.A., Guenther J.N., Parrish J.J. and Wiltbank M.C. (2002). Fertilization and early embryonic development in heifers and lactating cows in summer and lactating and dry cows in winter. J. Dairy Sci. 85, 2803-2812. Schefers J.M., Weigel K.A., Rawson C.L., Zwald N.R. and Cook N.B. (2010). Management practices associated with conception rate and service rate of lactating Holstein cows in large commercial dairy herds. J. Dairy Sci. 93, 1459-1467. Schrick F.N., Hockett M.E., Saxton A.M., Lewis M.J., Dowlen H.H. and Oliver S.P. (2001). Influence of subclinical mastitis during early lactation on reproductive performance. J. Dairy Sci. 84, 1407-1412. Tibbo K., Wiener G. and Fielding D. (1994). A review of performance of the Jersey breed of cattle and its crosses in the tropics in relation to the Friesian or Holstein and indigenous breeds. Anim. Breed. Abstr. 62, 719-757. Torres-Junior J.R.S., Pires M.F.A., De Sa W.F., De Ferreira A. M., Viana J.H.M., Camargo L.S.A., Ramos A.A., Folhadella I.M., Pallesseni J., Freitas C., Clemente de Sa Filho M.F., Paula Lopes F.F. and Baruselli P.S. ( 2008). Effect of maternal heat stress on follicular growth and oocyte competence in Bos indicus cattle . Theriogenology. 69, 155-166. Ulberg L.D. and Burfening P.J. (1967). Embryo death resulting from adverse environment on spermatozoa and ova. J. Anim. Sci. 26, 571-577. Vaccaro L.R. (1973). Some aspects of the performance of purebred and crossbred dairy cattle in the tropics. Part I- Reproductive efficiency in females. Anim. Breed. Abstr. 41, 571-589. Vincent C.K. (1972). Effect of season and high environmental temperature on fertility in cattle: a review. J. Amer. Vet. Med Assoc. 161, 1333-1337. Walsh S.W., Williams E.J. and Evans A.C.O. (2011). A review of the causes of poor fertility in high milk producing dairy cows. Anim. Reprod. Sci. 123, 127-138. Wolfenson D., Flamenbaum I. and Berman A. (1988). Hyperthermia and body energy store effects on estrus behavior, conception rate and corpus luteum function in dairy cows. J. Dairy Sci. 71, 3497-3504. Wolfenson D., Roth Z. and Meidan R. (2000). Impaired reproduction in heat-stressed cattle: basic and applied aspects. Anim. Reprod. Sci. 60, 535-547 Wolff L.K. and Monty D.E.J. (1974). Physiological response to intense summer heat and its effect on the estrous cycle of non- lactating and lactating Holstein-Friesian cows in Arizona. Am. J. Vet. Res. 35, 187-192. Zakari A.Y., Molokwu E.C.I. and Osori D.I.K. (1981). Effect of rectal and ambient temperatures and humidity on conception rates. Theriogenology. 16, 331-336.