Revista Veterinaria Zacatecas 2004 - UAZ

hecho que coincide con los resultados obtenidos
por Kirkwood et al. 19 Lo cual se puede deber al
efecto de las gonadotropinas sobre la
superovulación. La mayor incidencia de
ovulaciones conduce a la mayor presencia de
cuerpos lúteos en los ovarios, en donde al final de
la gestación de la cerda se produce relaxina;
hormona que se relaciona con el crecimiento de
las glándulas mamarias y, por consiguiente con la
producción de leche durante la lactancia. 18
LITERATURA CITADA
1. Rozeboom KF, Troedsson MHT,
Shurson GC, Hawton JD, Carbo BG.
Late estrus or metaestrus insemination
after estrual insemination decreases
farrowing rate and litter size in swine. J
Anim Sci 1997; 75: 2323-2327.
2. Knox RV, Rodriguez-Zas SL, Miller
GM, Willenburg KL, Robb JA.
Administration of P.G. 600 to sows at
weaning and the time of ovulation as
determined by transrectal ultrasound. J
Anim Sci 2001; 79: 796-802.
3. Knox RV, Tudor KW, Rodriguez-Zas
SL, Robb JA. Effect of subcutaneous vs
intramuscular administration of P.G. 600
on estrual and ovulatory response of
prepuberal gilts. J Anim Sci 2000; 78:
1732-1737.
4. Gill JL. Design and analysis of
experiments in the animal and medical
sciences. The Iowa State University
Press/ Ames, Iowa, USA, 1978.
5. Stevernik DWB, Soede NM, Browman
EG, Kemp B. Semen backflow after
insemination and its effect on fertilization
results in sow. Anim Rerod Sci 1998; 54:
109-119.
6. Waberski D. Effects of semen
components on ovulation and
fertilization. J Reprod Fertil 1997; 52
(Suppl): 105-109.
7. Soede NM, Wetzels CCH, Zondag W, de
Koning MAI, Kemp B. Effects of time of
insemination relative to ovulation, as
determined by ultrasonography, on
fertilization rate and accessory sperm
count in sow. J Reprod Fertil 1995; 104:
99-106.
8. Waberski D, Weitze KF, Gleumes T,
Schwarz M, Willman T, Petzoldt R.
Tamaño de la camada en cerdas
165
Effect of time of insemination relative to
ovulation on fertility with liquid and
frozen semen. Theriogenology 1994; 42:
831-840.
9. Flowers WL, Esbenshade KL.
Optimizing management of natural and
artificial matings in swine. J Reprod
Fertil 1993; 48 (Suppl): 217-228.
10. Anderson LL. Cerdos. In: Hafez ESE,
Hafez B. Reproducción e inseminación
artificial en animales. México: McGraw-
Hill Interamericana 2002: 188-198.
11. Dziuk PJ. Reproduction in pigs. In:
Cupps PT. Reproduction in domestic
animals. Fourth ed. Academic Press, Inc,
San Diego, Ca, 1991.
12. Lancanster RT, Foxcroft GR, Boland
MP, Edwards S. Fertility of sows injected
with exogenous estradiol and/or
gonadotropins to control post-weaning
estrus. Anim Reprod Sci 1985; 8: 365-
373.
13. Estienne MJ, Hartsock TG. Effect of
exogenous gonadotropins on the
weaning-to-estrus interval in sows.
Theriogenology 1998; 49: 832-828.
14. Valencia J. Ciclo estral. En Fisiología de
la Reproducción Porcina. Ed Trillas,
1986: 33-54.
15. Pope WF, Lawyer MS, Nara BS, First
NL. Effect of asynchronous on embryo
survival and range of blastocyst
development in swine. Biol Reprod 1986;
35: 133-137.
16. Shimatsu Y, Uchida M, Niki R, Imai H.
Induction of superovulation and recovery
of fertilized oocytes in prepubertad
miniature pigs after treatment with
PG600. Theriogenology 2000; 53: 1013-
1022.
17. Wu MC, Hentzel MD, Dziuk PJ. Effects
of stage of gestation, litter size and
uterine space on the incidence of
mummific fetuses in pig. J Anim Sci
1988; 66: 3202-3207.
18. Escobar-Medina FJ. Crecimiento de las
glándulas mamarias de la cerda y su
relación con la ganancia diaria de peso de
los lechones. Veterinaria Zacatecas 2003;
2: 77-87.
19. Kirkwood RN, Aherne FX, Foxcroft GR.
Effect of gonadotropin at weaning on
reproductive performance of primiparous
sows. Swine Health Prod 1998; 6: 51-55.