Effect of body composition at selection on reproductive development in Large White gilts

• Published in: Journal of animal science 1997-07, Vol.75 (7), p.1764-1772
• Main Authors: Gaughan, J.B. (University of Queensland, Gatton, Australia.), Cameron, R.D.A, Dryden, G.M, Young, B.A
• Format: Article
• Language: English
• Subjects: ADIPOSE TISSUES; AGE; Aging - physiology; Animal Nutritional Physiological Phenomena; Animal productions; Animal reproduction; Animals; BACKFAT; BARDIERE; Biological and medical sciences; Body Composition - genetics; Body Composition - physiology; BODY FAT; BODY PROTEIN; BODY WEIGHT; Body Weight - physiology; BREEDS (ANIMALS); CERDAS; CICLO ESTRAL; CORPS JAUNE; CORPUS LUTEUM; Corpus Luteum - physiology; CUERPO LUTEO; CYCLE OESTRAL; EDAD; Estrus - physiology; FAT THICKNESS; Female; FOLICULOS OVARICOS; FOLLICLES; FOLLICULE OVARIEN; Fundamental and applied biological sciences. Psychology; GROWTH RATE; Hogs; INDICE DE CRECIMIENTO; MADUREZ SEXUAL; MATURITE SEXUELLE; Nutrition; OESTROUS CYCLE; Ovarian Follicle - physiology; OVARIAN FOLLICLES; PESO CORPORAL; POIDS CORPOREL; PROTEINAS; PROTEINE; PROTEINS; PUBERTY; RACE (ANIMAL); RAZAS (ANIMALES); Reproduction - physiology; Selection, Genetic; Sexual Maturation - physiology; SEXUAL MATURITY; SOWS; Swine - genetics; Swine - physiology; TAUX DE CROISSANCE; TEJIDO ADIPOSO; Terrestrial animal productions; TISSU ADIPEUX; TOCINO DORSAL; TRUIE; Vertebrates; Weight Gain - physiology
• ISSN: 0021-8812; 1525-3163; 0021-8812
• DOI: 10.2527/1997.7571764x

Fifty-four Large White gilts were used to determine the effect of body composition at selection (145 d of age) on the onset of puberty and subsequent reproductive development until 202 d of age. Gilts were assigned to one of three groups based on their backfat depth at selection: 10 to 12 mm (L), 13 to 15 mm (M), and 16 to 18 mm (F). All of the F gilts, 92% of the M gilts, and 67% of the L gilts reached puberty by slaughter at 202 d of age. Data from a subgroup (first 67% to reach puberty in each group; L = Lp, M = Mp, and F = Fp) was also used. The M (Mp) and F (Fp) gilts reached puberty at 172 d (166 d) and 170 d (166 d) of age, respectively, but the L (Lp) gilts at 184.5 d were 12 d (18 d) older than M (P .05), Mp (P .001), and F (P .01), Fp (P .001) gilts. The Lp (97.68 kg) and Mp (98.33 kg) gilts were lighter (P .01) than Fp (108.72 kg) gilts at puberty. There were no differences (P .05) among the L, M, and F gilts in terms of backfat depth or weight at puberty. The L (Lp) gilts had a mean of 1.16 (1.75) estrous cycles, which was lower (P .01) than for M (Mp) and (P .01) F (Fp) gilts, with 1.96 (2.29) and 2.25 (2.33) cycles, respectively. L (Lp) gilts had fewer (P .05) follicles, 13.14 (12.63), than either M (Mp), 19.08 (18.71), or F (Fp), 18.25 (17.42) gilts. The number of corpora lutea was not influenced (P .05) by grouping at selection, but Fp gilts had fewer (P .05) corpora lutea than Mp or Fp gilts. Live weight at slaughter was not influenced (P .10) by grouping at selection or subgrouping at puberty. The L gilts with a mean of 18.05 mm of backfat at slaughter were leaner (P .05) than the F (21.66 mm) but not (P .10) the M gilts (19.41 mm). Subgrouping had no effect. Fat deposition and protein deposition were higher (P .05) in those animals that attained puberty. We conclude that the rate of fat and protein deposition seems to be one of the determinants of puberty attainment