Changes With Age in the Occurrence of C19 Steroids in the Testis and Submaxillary Gland of the Boar

Abstract

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 occurrence of C19 steroids in testicular tissue and submaxillary glands of intersex pigs in relation to morphological characteristics

“…Table 2) ; small quantities of testosterone and 5a-dihydrotestosterone (<2 µg/100 g) were also found in some of the submaxillary glands. Pooled samples of 16-androstenes gave similar colour reactions and Rf values to authentic compounds on thin-layer chromatography, and all C19 steroid samples gave similar retention times to authentic compounds on gas-liquid chromatography as described previously (Booth, 1975). Small amounts of 3ß-androstadienol and androstadienone which had been extracted from testicular tissue, and 3ß-androstadienol from submaxillary glands, were conclusively identified by combined gas-liquid chromatography-mass spectrometry (for details of mass spectra, see Booth, 1975).…”

“…The methods used for the extraction, identification, and measurement of Ci9 steroids including 16-androstenes in testicular tissue and submaxillary glands, were identical to those previously described (Booth, 1975).…”

“…It has been established that 16-unsaturated C19 steroids (16-androstenes), which are produced in large quantities by the boar testis (Gower, 1972;Booth, 1975), are responsible for taint in boar meat (Patterson, 1968 ;Berry & Sink, 1971). Pig carcases that are tainted are responsible for economic losses, and Bishop (1969) has suggested that some of these carcases could be of intersex pigs with a predominantly female phenotype, but possessing intra-abdominal testicular tissue.…”

“…The aims of the present study on intersex pigs were (i) to study in greater detail than hitherto the occurrence of C19 steroids in the testicular tissue of the intersex pig; (ii) to find out if 16-androstenes are also present in this testicular tissue and in the submaxillary glands in significant quantities, and therefore likely to be the factors responsible for taint in these animals ; (iii) (Booth, 1975) ; and (iv) to relate the levels of steroids to the development of male characteristics in the intersex pig.…”

Influence of boar contact on attainment of puberty in gilts after removal of the olfactory bulbs

“…only sows with some residual bulb material continuing to cycle normally. More recent evidence suggests that when the operation is performed on prepubertal gilts, it is followed by normal oestrous cycles and reproductive performances (Meese & Baldwin, 1975a, b (Signoret, 1970), and the 16-unsaturated C,9 steroids which are major testicular steroids in the pig, and accumulate in high concentration in the submaxillary glands (Gower, 1972;Booth, 1975) and saliva of boars (Booth & Baldwin, 1980), have signalling pheromone properties (Reed, Melrose & Patterson, 1974). However, no primer pheromone has yet been identified in the boar (Kinsey, Carlson, Proud & Zimmerman, 1976;Kirkwood & Hughes, 1980).…”