" For him, nothing was off limits, "whether it be the sublime viscosities of a fish-eye, the slithery cerebellum of a bird, the spermatozoal marrow of a bone or the soft and swampy opulence of an oyster.
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Journal of Reproduction and Fertility 15: 15-25.Amann, R.P., Johnson, L., Thompson, D.L. & Pickett, B.W. (1976). Daily spermatozoal production, epididymal spermatozoal reserves and transit time of spermatozoa through the epididymis of the rhesus monkey. Biology of Reproduction 15: 586-592.
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Gonadal and epididymal sperm reserves in the rabbit; Estimation of the daily sperm production. Journal of Reproduction and Fertility 15: 15-25.Amann R.P., Johnson L., Thompson D.L. & Pickett B.W. (1976). Daily spermatozoal production, epididymal spermatozoal reserves and transit time of spermatozoa through the epididymis of the rhesus monkey.
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Advances in Spermatozoal Phylogeny and Taxonomy. Mémoires du Muséum National d'Histoire Naturelle, 166, 564 pp. Paris: Éditions du Muséum. (details) ultrastructure of flatworms and deep-sea fauna Richer de Forges, Bertrand & Justine Jean-Lou (eds) 2006 — Tropical Deep-Sea Benthos volume 24.
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Decapacitation factor (DF) is composed of factors in seminal plasma which modulates the fertilizing ability of spermatozoa. The activity is achieved by interaction between cholesterol, phospholipids and fibronectin-like substances and delivered via small vesicles in seminal plasma. DF prevents onset of capacitation. Physiologically it is achieved through spermatozoal membrane stabilization by maintaining physiological cholesterol/phospholipid ratio.
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The diploid number of chromosomes in the cheetah is 38, the same as in most other felids. The cheetah was the first felid observed to have unusually low genetic variability among individuals, which has led to poor breeding in captivity, increased spermatozoal defects, high juvenile mortality and increased susceptibility to diseases and infections. A prominent instance was the deadly feline coronavirus outbreak in a cheetah breeding facility of Oregon in 1983 which had a mortality rate of 60%—higher than that recorded for previous epizootics of feline infectious peritonitis in any felid. The remarkable homogeneity in cheetah genes has been demonstrated by experiments involving the major histocompatibility complex (MHC); unless the MHC genes are highly homogeneous in a population, skin grafts exchanged between a pair of unrelated individuals would be rejected.
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Apart from breaching of blood-testis barrier, epididymal distension, raised intraluminal pressure, and sperm granuloma formation leading spermatozoal phagocytosis seem to be contributing factors. As of 2017, it is unclear how or why women generally do not develop ASA, and why some women do develop them; the clearest correlations are that women whose male partners have ASA in their semen are more likely to have ASA, and women with ASA tend to react only to their partner's sperm and not to other men's sperm. The hypotheses for how women form ASA, as of 2017, includes cross-reactivity with microbial antigens, antibodies raised against ASA in their partner's semen, and a cytokine-driven immune response to ASA in their partner's semen. In women, spermatozoa in the genital tract after intercourse are not a factor in the production of antisperm antibodies.
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Until the late 1990s, captive Asiatic lions in Indian zoos were haphazardly interbred with African lions confiscated from circuses, leading to genetic pollution in the captive Asiatic lion stock. Once discovered, this led to the complete shutdown of the European and American endangered species breeding programs for Asiatic lions, as its founder animals were captive-bred Asiatic lions originally imported from India and were ascertained to be intraspecific hybrids of African and Asian lions. In North American zoos, several Indian-African lion crosses were inadvertently bred, and researchers noted that "the fecundity, reproductive success, and spermatozoal development improved dramatically." DNA fingerprinting studies of Asiatic lions have helped in identifying individuals with high genetic variability, which can be used for conservation breeding programs. In 2006, the Central Zoo Authority of India stopped breeding Indian-African cross lions stating that "hybrid lions have no conservation value and it is not worth to spend resources on them".
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