Summary. After extraction from the testes of boars of different ages, C19 steroids including 16-androstenes were determined by gas-liquid chromatography. Similarly, 16-androstenes were determined in the submaxillary glands of these boars. A high concentration of testosterone was found in the testes of 84-day-old fetuses, and this might be significant in the differentiation of male behaviour. The amount of testosterone exceeded that of androstenedione during postnatal development, and dehydroepiandrosterone and 5-androstenediol as free and sulphates were found in high concentrations particularly in postpubertal boars, suggesting that the 5-ene pathway for the synthesis of testosterone might be important. There was a change in the predominance of individual 16-androstenes in the testis during development, which closely paralleled the sequence for the biosynthesis of these compounds proposed from previous studies in vitro. Whereas the amount of 5\ g=a\ \ x=r eq-\ androst-16-en-3\g=b\-ol exceeded that of 5\g=a\-androst-16-en-3\g=a\-olin postpubertal testes, 5\g=a\-androst-16-en-3\g=a\-olwas predominant in the submaxillary glands at all ages. The high concentration of 16-androstenes found in the mature boar, are discussed in relation to their release as pheromones and as factors responsible for taint in boar meat.
The growth of the pituitary and of the reproductive tract of Suffolk rams from birth to 168 days of age has been studied. Pituitary icsh and fsh concentrations were determined by bio-assay. The pattern of testicular androgen production has been examined using chemical and histological techniques and the relationship to spermatogenesis studied. Pituitary gonadotrophin content increased sharply from 42 days of age but was only weakly correlated with other parameters measured.The androstenedione : testosterone ratio was at its narrowest at birth; however, testosterone was the predominant androgen from birth onwards. Androgen concentration fluctuated but the total content increased with increase in testicular weight. Fructose was present in the seminal vesicles from birth and citric acid from 14 days; citric acid concentration was about one-tenth that of fructose. There was a significant correlation between testicular androgen content and the fructose and citric acid concentration and content of the seminal vesicles.Seminiferous tubule diameter was significantly correlated with most of the parameters measured. Testicular weight increased sharply from 42 days of age. Androgen production was present at birth and preceded spermatogenesis which began when testis weight exceeded 10 g, which was after 56 days of age. Spermatozoa were present in the seminiferous tubules at 112 days of age. J. D. Skinner et al. development of the seminal vesicles, prostate and bulbo-urethral gland, which in the late-term foetus resemble those in the castrated adult.The object of the present study was to examine the sexual development of the Suffolk ram from birth to 168 days of age. MATERIALS AND METHODSMaterial was provided by fifty-four Suffolk lambs allocated at random into six groups for slaughter at intervals of 14 days, from birth to 168 days. To obtain sufficient material for assay the numbers in the groups were as follows: ten at birth, eight at 14 days, six at 28 days, four from 42 to 70 days, two from 84 to 154 days, and six at 168 days. Histological observations on the testes of a 103-day-old ram foetus and a 105-day-old ram have also been included.The lambs were weighed before slaughter, after which the head was im¬ mediately removed, the pituitary gland removed, weighed, sealed in tin foil and frozen over solid C02 within 3 min of slaughter.The testes were then removed, weighed and slices taken for histology, the testes were then stored over solid C02. The amount of testosterone and androstenedione in the testes was estimated later. The remainder of the tract was dissected out, the accessory glands weighed individually, slices taken for histology and the seminal vesicles then stored over solid C02. The amount Sexual development in the ram 465 were evaporated to dryness and preliminarily chromatographed using thin-layer chromatography, medium Silica-gel GF 254 and solvent system CHCl3:EtoAc (2:1). This step finally removed contaminating substances which would otherwise have interfered with the resolution of the paper chromatograp...
Prepubertally castrated boars received subcutaneous injections twice weekly, from 12 to 38 weeks of age, of testosterone or 5-androstenediol (5-androstene-3 beta,17 beta-eiol) (2 mg/5 kg), or each of these steroids in combination with oestrone (1 mg/5 kg). All steroid treatments induced growth and secretory activity of the accessory organs. The prostate was maintained best by testosterone, and the seminal vesicles by 5-androstenediol. No specific effects of oestrone on these organs were found. Champing of excess saliva was induced in all treated pigs when they were introduced to an oestrous gilt, but only boars receiving testosterone displayed intense mating behaviour including mounting and, in 3 animals, ejaculation; no specific effects of oestrone on behaviour were seen. Low normal levels of unconjugated androgen, and normal to high levels of unconjugated oestrogen were circulating in the treated pigs. There was evidence that peripheral metabolism of exogenous steroids had occurred: 5-androstenediol to testosterone, these two androgens to oestrogen, and sulphation of oestrogen. The sulphate conjugates of dehydroepiandrosterone, 5-androstenediol and oestrone predominated in the peripheral plasma of mature intact boars. Concentrations of 3 alpha-androstenol (5 alpha-androst-16-en-3 alpha-ol) in the submaxillary glands of androgen-treated pigs were similar to those in untreated castrates, thus indicating that androgens are probably not precursors of the pheromonal 16-androstene steroids in vivo.
An enzyme-linked immunosorbent assay has been developed for the direct assay of cortisol in the saliva of man, sheep, calf and pig. The assay is sensitive (integral of 1pg), highly specific and reproducible, and has the advantage over radioimmunoassay in being cheaper and quicker to carry out. The relatively-non invasive method of collecting saliva on cotton buds coupled with simple assay equipment provide a good potential for assessing cortisol status in studies on stress and welfare in farm animals as well as the possibility of monitoring cortisol status in mammals generally.
Submaxillary glands of mature Göttingen miniature pigs were examined for the presence of a sexual dimorphism. Gland weights, serous cell hypertrophy and total protein in the glands were much greater in male than female pigs. High concentrations of the pheromonal 16-androstene steroids were present in the glands of males and exceeded 2 mmol/g in some animals; this was primarily due to 5 alpha-androst-16-en-3 alpha-ol. The high concentration of 16-androstene steroids in boar glands was correlated with the presence of large amounts of binding protein for these steroids in the glands; smaller amounts of the binding protein were detected in female glands. These findings are similar to those found in domestic pigs, but the degree of sexual dimorphism assessed from these findings is more extreme in the miniature pig.
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