Puberty in male collared peccary (Pecari tajacu) determined by quantitative analysis of spermatogenic cells

Abstract

Biological studies are necessary for the management of wildlife in captivity, and knowledge of reproduction is one of the important features for increasing production. The objective of the research was to determine the age at which male collared peccaries reach puberty. Testicular samples of 15 animals, aged 7 to 16 months, distributed into five groups (G1, G2, G3, G4 and G5) were used. The testes showed considerably increased weight, length and width (p < 0.05) from G1 to G3, whereas, from this group onward, the development of this organ was slower. There was positive correlation (p < 0.001) between the following testicular parameters: weight and length (r = 0.97), weight and width (r = 0.88), length and width (r = 0.92). Regarding the diameter of seminiferous tubules, an increase was observed (p < 0.05) from G1 to G4. The total number of spermatogenic cells increased significantly (p < 0.05) until G3 and then it stabilized. There was also positive correlation between testis weight and tubular diameter (r = 0.99, p < 0.001), and testis weight and spermatogenic cells (r = 0.98, p < 0.001). The number of Sertoli cells decreased significantly (p < 0.05) from G1, when they were undifferentiated as support cells, to G5, when they occurred together with the complete line of spermatic cells. The results demonstrate that the reproductive development of peccaries can be classified into the following stages: impuberty (G1, 7-8 months); pre-pubertal (G2, 9-10 months); pubertal (G3, 11-12 months); post-pubertal 1 (G4, 13-14 months); and post-pubertal 2 (G5, 15-16 months). Based on the histological analyses, puberty in the male collared peccary was determined to occur between 11 and 12 months of age. Keywords: reproduction; testicles; spermatogenesis, Tayassuidae. Puberdade em macho de cateto (Pecari tajacu) determinada pela análise quantitativa das células espermatogênicas resumoEstudos biológicos são necessários para o manejo da vida silvestre em cativeiro, e o conhecimento da reprodução é um dos aspectos importantes para o aumento da produção. Esta pesquisa teve como objetivo determinar a idade da puberdade do cateto macho. Foram utilizadas amostras testiculares de 15 animais, entre 7 a 16 meses, distribuídos em cinco grupos (G1, G2, G3, G4 e G5). Os testículos aumentaram no peso, comprimento e largura consideravelmente (p < 0,05) do G1 ao G3, enquanto que, a partir deste grupo, o desenvolvimento desse órgão foi mais lento. Houve correlação positiva (p < 0,001) entre os seguintes parâmetros testiculares: peso e comprimento (r = 0,97), peso e largura (r = 0,88), comprimento e largura (r = 0,92). Com relação ao diâmetro tubular, observou-se um aumento (p < 0,05) do G1 ao G4. A quantidade total de células espermatogênicas aumentou significativamente (p < 0,05) até o G3, e se estabilizou a partir deste grupo. Houve correlação positiva entre o peso testicular e o diâmetro tubular (r = 0,99, p < 0,001), bem como o peso testicular e as células espermatogênicas (r = 0,98, p < 0,001). A quantidade de células de Sertoli re...

Use of Non‐invasive Methods for Evaluating the Testicular Biometry in Collared Peccaries (Pecari tajacu Linnaeus, 1758)

“…In this way, the captive breeding could reduce the hunting pressure on wild populations (Abbott and Van Kooten, ), and it could contribute towards obtaining valuable information for proper reproductive management practices. It could also assist in the selection of individuals, increase in productivity and efficiency, and for genetic improvement (Guimarães et al., ).…”

“…Only a few attempts were made to directly compare the accuracy of formulas, using water displacement, to determine the true testicular volume in dogs (Paltiel et al., ; Gouletsou et al., ) and humans (Sakamoto et al., ). In wild animals, no similar studies are reported, although the interest in these species has been renewed for fundamental and applied research in reproductive physiology, as quoted with regard to the collared peccary (Peixoto et al., ; Guimarães et al., ).…”

Derivation of sperm from xenografted testis cells and tissues of the peccary (Tayassu tajacu)

“…Under captivity conditions, sperm release (puberty) in the seminiferous tubule lumen in the collared peccary is first observed at 11-12 months of age (Guimarães et al 2013). Therefore, probably due to the more mature hypothalamic-pituitary-gonadal axis in the recipient mice (Rodriguez-Sosa & Dobrinski 2009), the first spermiation in peccary testis tissue xenograft is clearly advanced , Oatley et al 2004, Rathi et al 2006, Arregui et al 2008, Abrishami et al 2010, Abbasi & Honaramooz 2011, Gourdon & Travis 2011 Figure 7 Collared peccary sperm harvest and fertility test.…”

“…Using standard procedures, ovaries from sexually mature female collared peccaries (nZ4) were obtained by ovariectomy (Guimarães et al 2013). Thirty-two cumulus-oocyte complexes (COCs) were collected from follicles in TCM 199 (Sigma) supplemented with 10% FBS (Gibco, Life Technologies), 20 mM HEPES (Dojindo Laboratories, Kumamoto, Japan), 100 IU/ml penicillin G potassium (Sigma), and 0.1 mg/ml streptomycin sulfate (Sigma).…”

Sexual behavior of Pecari tajacu (Cetartiodactyla: Tayassuidae) during periovulatory and early gestation periods

“…The study was conducted with 20 adult female collared peccaries (6 pluriparous, 13 nulliparous and 1 primiparous) and 12 males, aged between 8 months and 13 years ( Table 1). All animals were adults, since puberty is achieved at seven months in females and at 12 months in males (Nogueira-Filho et al, 2004;Mayor et al, 2007b;Guimarães et al, 2013).…”