Corporal and testicular biometry in wild boar from birth to 12 months of age

Abstract

RESUMO Biometria corporal e testicular de javalis do nascimento aos 12 meses de idadeObjetivou-se, com esta pesquisa, investigar o desenvolvimento testicular e corporal de javalis (Sus scrofa scrofa), do nascimento aos 12 meses de idade, avaliando-se, em cada faixa etária, o peso corporal, o desenvolvimento biométrico dos testículos e o índice gonadossomático (IGS). Utilizaram-se 52 javalis machos, provenientes de um criatório comercial, devidamente regulamentado pelo IBAMA. Os animais foram pesados e divididos em 13 grupos experimentais; os testículos foram coletados por orquiectomia unilateral e, em seguida, pesados em balança analítica e mensurados comprimento, largura e espessura. Os valores de peso corporal e as medidas testiculares foram crescentes, após o nascimento, sendo sua variação mais acelerada no primeiro mês e aos nove meses. Inicialmente, o padrão de crescimento testicular, do nascimento aos nove meses de idade, acompanhou o crescimento corporal e o índice gonadossomático variou de 0,07 a 0,09%. Em seguida, entre nove e 11 meses, o valor de crescimento testicular foi superior ao de crescimento corporal e o índice gonadossomático variou de 0,09 a 0,16%. Por fim, após os 11 meses de idade, os valores crescimento corporal e dos testículos voltaram a se comportar de forma semelhante. Conclui-se que o desenvolvimento do peso corporal, a biometria testicular e o IGS tiveram crescimento mais acelerado aos nove meses de idade.Palavras-chave: peso corporal, índice gonadossomático, desenvolvimento testicular, Sus scrofa scrofa. Received: 17/07/2009; Accepted: 27/12/2012 Corporal and testicular biometry in wild boar from birth to 12 months of ageThe aim of this tudy was to evaluate corporal and testicular development in wild boars (Sus scrofa scrofa) from birth to 12 months of age, evaluating body weight, biometric testicular parameters, and gonadosomatic index. Thirty-nine male wild boars from a commercial farm licensed by IBAMA were used in the study. The animals were weighed and assigned to 13 experimental groups. The testes were recovered through unilateral orchiectomy, weighed on an analytical balance and measured for length, width and thickness. Body weight and testicular measures increased with the age, up to 12 months, and were more accelerated in the first and ninth months. Initially the testicular growth pattern, between zero and nine months, followed the body growth, and the gonadosomatic index varied from 0.07 to 0.09%. Between 9 and 11 months, the testicular growth was superior to the body growth, and the gonadosomatic index varied from 0.09 to 0.16%. Finally, after 11 months of age, testicular and body growth had a similar behavior. In conclusion, body weight, testicular biometry, and gonadosomatic index development accelerated in the ninth month.

Reproductive characteristics of wild boar males (Sus scrofa) under different environmental conditions

“…The ratio of body and testicular weight was initially more or less constant; this was followed by rapid growth starting at month 8 and peaking during month 10, which could be caused by impending puberty, as described by Murta et al (2013) and Ferreira et al (2004). After that, the growth gradually slowed and reached constant values again.…”

“…As puberty approaches, the growth accelerates due to the expansion of lumen and thickening of the walls of seminiferous tubules. After reaching their sexual maturity, the growth slightly slows down due to an increase in the volume of connective tissue (Schinckel et al 1983;Assis Neto et al 2003;Murta et al 2013). This accelerated growth in puberty and the post-pubertal period is related to an increase in the volume of Sertoli cells and the mitotic division of reproductive cells in seminiferous tubules, which leads to the formation of primary spermatocyte out of spermatogonia.…”

“…While females need to be sexually mature as well as be adequately physically developed and have sufficient fat reserves in order to take part in active reproduction, the reproductive ability of a young male is determined mainly by the development of his gonads and their capacity for producing viable sperm. In the last decades, young females have begun to reproduce en masse, it is therefore likely that environmental conditions have the same effect on males, which should be capable of fertilizing females of the same age (Murta et al 2013).…”

Analysis of testicular variables, semen motility and kinematics‐derived indexes in boar using a CASA‐Mot system

“…It is described that 7.86% of the testicle weight estimated in suidae species is due to tunica albuginea (Macedo et al, ). However, it was reported in wild swine that up to 35.71% of the actual testicle weight consists of the tunica albuginea (Murta, Costa, Santos, Faria, & Paula, ). This fact is important since estimated testicular weight includes tunica and epididymis, which justifies the differences found for testicular weight.…”

“…Testicular weight in swine has a high and positive correlation with age ( r = 0.90, p < .05) (Murta et al, ). Another important finding was that individuals from crosses with Pietrain presented greater testicular measurements ( p ≤ .05) compared to other genetic groups.…”