EFFECT OF AGE AT FIRST FARROWING AND HERD MANAGEMENT ON LONG-TERM PRODUCTIVITY OF SOWS

Incidence of age at first farrowing and herd management on reproductive lifetime of sows was analysed on 38,349 Large White× Landrace animals and their 171,178 litters. Gilts were born in 1990 and located in 976 French herds. Data included dates of birth and entry in the herd, breeding, farrowing and weaning events, reason for and parity at culling. The herds were classified according to age at first farrowing, as `early' (337 days), `usual' (356 days) or `late' (371 days). The average number of piglets born alive and weaned per litter increased with age at first farrowing (P<0.001), especially at parity one. The total number of piglets produced per sow and the parity number at culling decreased with the age at first farrowing (P<0.001). The best reproductive results were obtained in the `usual' management group, with first farrowing at 356 days of age on average. Within each herd management, the older gilts at first farrowing obtained the lowest performance, and the youngest had the best ones. These results suggest that the effect of age at first farrowing on subsequent performance of gilts is highly dependent on the general sow herd management.

[1]  H. Lagant,et al.  Analyse expérimentale de l'influence de l'âge à la première mise bas et du type génétique sur la productivité de la truie , 1996 .

[2]  D. A. Smith,et al.  The effect of mating age on the reproductive performance, food utilisation and liveweight change of the female pig , 1980 .

[3]  S. Swaminathan,et al.  A Survey of Productivity and its Component Interrelationships in Canadian Swine Herds , 1986 .

[4]  D. Rozeboom,et al.  Influence of gilt age and body composition at first breeding on sow reproductive performance and longevity. , 1996, Journal of animal science.

[5]  R. Huirne,et al.  Evaluation of optimal age at first conception in gilts from data collected in commercial swine herds. , 1994, Journal of animal science.

[6]  A. Archibong,et al.  Factors contributing to early embryonic mortality in gilts bred at first estrus. , 1987, Journal of animal science.

[7]  J. D. Chapman,et al.  Relationship of Age at First Farrowing and Size of First Litter to Subsequent Reproductive Performance in Sows , 1978 .

[8]  E. Beltranena,et al.  Endocrinology of nutritional flushing in gilts , 1991 .

[9]  D. Mahan,et al.  Effect of initial breeding weight and management system using a high-producing sow genotype on resulting reproductive performance over three parities. , 1993, Journal of animal science.

[10]  R. King.  Effect of live weight and body composition of gilts at 24 weeks of age on subsequent reproductive efficiency , 1989 .

[11]  C. Whittemore.  Nutrition reproduction interactions in primiparous sows , 1996 .

[12]  Jean-Yves Dourmad,et al.  Effect of weaning-to-conception interval and lactation length on subsequent litter size in sows , 1997 .

[13]  L. Clark,et al.  Factors influencing litter size in swine: parity-one females. , 1988, Journal of the American Veterinary Medical Association.

[14]  C. Legault,et al.  Genetic variability of age and weight at puberty, ovulation rate and embryo survival in gilts and relations with production traits , 1996, Genetics Selection Evolution.

[15]  R. Macpherson,et al.  Performance of sows first mated at puberty or second or third oestrus, and carcass assessment of once-bred gilts , 1977 .

[16]  A. J. Barr,et al.  SAS user's guide , 1979 .

[17]  A. Prunier.  Influence of age at nutritional restriction on growth and sexual development of gilts. , 1991, Reproduction, nutrition, development.

[18]  J. Walton,et al.  REPRODUCTIVE PERFORMANCE OVER FOUR PARITIES OF GILTS STIMULATED TO EARLY ESTRUS AND MATED AT FIRST, SECOND OR THIRD OBSERVED ESTRUS , 1990 .

[19]  K. M. Irvin,et al.  Factors Affecting Reproductive Performance in Swine , 1987 .