Age-related changes in plasma LH and testosterone concentration profiles and fat 5α-androstenone content in the young boar

摘要: Twenty-four-hour secretory profiles of LH and testosterone were determined in young male pigs at 100, 125, 150 175 days age. A total 22 (5–6 per age group) was obtained. measured mean intervals 9 min. Fat 5α-androstenone levels each the 12 boars involved experiment. No significant diurnal variation plasma hormone noticed. No age-related change observed frequency or duration peaks. Absolute amplitude peaks concentration higher 100-day-old than other groups (2.3 vs 1.6–1.7 ng/ml 1.5 1.1 respectively; P < 0.001). Testosterone more frequent 150-day-old (12.8 7.4 24 h; 0.05) while two intermediate. shorter 100–125-day-old (47–48 72 min; they intermediate 175-day-old animals. The significantly declined from 100 to whereas no occurred that onwards (absolute amplitude: 14.5, 9.1, 7.0 6.3 ng/ml; levels: 8.8, 5.6, 4.5 150, respectively). Patterns fat with very variable according animals, a litter effect (P Of studied, seven exhibited peri-pubertal rise level (“high 5α-androstenone” HA animals) five did not (“low LA animals). There difference between for criteria. Data present experiment indicate post-pubertal decline is related decrease and, lesser extent, reduction their frequency. close relationship found criteria nor levels.