Effect of scrotal temperature on semen characteristics in Morada Nova rams

Native sheep breeds have satisfactory reproductive activity throughout the year, but nutritional and climatic factors such as high temperature during the dry period can affect the semen quality, causing a decrease in sperm motility and an increase in the percentage of morphologically abnormal sperm....

Full description

Bibliographic Details
Main Authors: Damares Betega Pereira, André Torres Geraldo, Camila de Miranda e Silva Chaves, Célia Raquel Quirino, Mauro Sartori Bueno, Ricardo Lopes Dias da Costa
Format: Article
Language:English
Published: Instituto de Zootecnia 2015-02-01
Series:Boletim de Indústria Animal
Subjects:
Online Access:http://10.153.18.28/index.php/bia/article/view/421
_version_ 1797744719929802752
author Damares Betega Pereira
André Torres Geraldo
Camila de Miranda e Silva Chaves
Célia Raquel Quirino
Mauro Sartori Bueno
Ricardo Lopes Dias da Costa
author_facet Damares Betega Pereira
André Torres Geraldo
Camila de Miranda e Silva Chaves
Célia Raquel Quirino
Mauro Sartori Bueno
Ricardo Lopes Dias da Costa
author_sort Damares Betega Pereira
collection DOAJ
description Native sheep breeds have satisfactory reproductive activity throughout the year, but nutritional and climatic factors such as high temperature during the dry period can affect the semen quality, causing a decrease in sperm motility and an increase in the percentage of morphologically abnormal sperm. To protect itself against the deleterious effect of high temperature, the testicle has a complex mechanism of thermoregulation sites. The scrotal skin has an important function in the maintenance of testicular temperature, since it is thin, poor in subcutaneous fat, relatively hairless and has a well-developed blood and lymphatic system, facilitating thermal loss by radiation and evaporation. This study aimed to evaluate the effect of scrotal temperature on sperm quality in Morada Nova sheep. Temperature was measured with a laser thermometer and three classes of average testicular temperature were established: class 1 = 28ºC to 31ºC, class 2 = 31.01ºC to 33ºC and class 3 = >33ºC. The ejaculate of each animal was collected using an artificial vagina for further evaluation of volume, aspect, whirling, motility and sperm vigor. Then the sperm concentration and morphology were determined by examination of moist slides. Means were compared by the t-test and chi-square test using the SAS software (SAS Inst., Inc., Cary, NC). There was no difference (P>0.05) for whirling (3.42±1.08%), concentration/mL (4.1x109±2x109), total concentration (3.9x109±1.1x109), coiled tails (42.46±14.48%), decapitation (1.58±3.67%), proximal (0.23±0.66%) and distal protoplasmic drop (0.04±0.2%), large defects (4.13±6.21%) and total defects (46.64±14.22%) in function of scrotal temperature. The variables volume, vigor, motility and piriform heads were different in relation to increased scrotal temperature (P<0.05). Sheep with class 3 scrotal temperature had presence of coiled tails and minor defects 7.37% and 7.49% less, respectively, than the sheep with scrotal temperature class 1, but class 2 did not differ from classes 1 and 3. Therefore, it can be concluded that the increase in scrotal temperature can influence semen characteristics.
first_indexed 2024-03-12T15:14:26Z
format Article
id doaj.art-cf275bd2f9174722a467205b75503b59
institution Directory Open Access Journal
issn 1981-4100
language English
last_indexed 2024-03-12T15:14:26Z
publishDate 2015-02-01
publisher Instituto de Zootecnia
record_format Article
series Boletim de Indústria Animal
spelling doaj.art-cf275bd2f9174722a467205b75503b592023-08-11T17:41:11ZengInstituto de ZootecniaBoletim de Indústria Animal1981-41002015-02-0171Effect of scrotal temperature on semen characteristics in Morada Nova ramsDamares Betega PereiraAndré Torres GeraldoCamila de Miranda e Silva ChavesCélia Raquel QuirinoMauro Sartori BuenoRicardo Lopes Dias da CostaNative sheep breeds have satisfactory reproductive activity throughout the year, but nutritional and climatic factors such as high temperature during the dry period can affect the semen quality, causing a decrease in sperm motility and an increase in the percentage of morphologically abnormal sperm. To protect itself against the deleterious effect of high temperature, the testicle has a complex mechanism of thermoregulation sites. The scrotal skin has an important function in the maintenance of testicular temperature, since it is thin, poor in subcutaneous fat, relatively hairless and has a well-developed blood and lymphatic system, facilitating thermal loss by radiation and evaporation. This study aimed to evaluate the effect of scrotal temperature on sperm quality in Morada Nova sheep. Temperature was measured with a laser thermometer and three classes of average testicular temperature were established: class 1 = 28ºC to 31ºC, class 2 = 31.01ºC to 33ºC and class 3 = >33ºC. The ejaculate of each animal was collected using an artificial vagina for further evaluation of volume, aspect, whirling, motility and sperm vigor. Then the sperm concentration and morphology were determined by examination of moist slides. Means were compared by the t-test and chi-square test using the SAS software (SAS Inst., Inc., Cary, NC). There was no difference (P>0.05) for whirling (3.42±1.08%), concentration/mL (4.1x109±2x109), total concentration (3.9x109±1.1x109), coiled tails (42.46±14.48%), decapitation (1.58±3.67%), proximal (0.23±0.66%) and distal protoplasmic drop (0.04±0.2%), large defects (4.13±6.21%) and total defects (46.64±14.22%) in function of scrotal temperature. The variables volume, vigor, motility and piriform heads were different in relation to increased scrotal temperature (P<0.05). Sheep with class 3 scrotal temperature had presence of coiled tails and minor defects 7.37% and 7.49% less, respectively, than the sheep with scrotal temperature class 1, but class 2 did not differ from classes 1 and 3. Therefore, it can be concluded that the increase in scrotal temperature can influence semen characteristics.http://10.153.18.28/index.php/bia/article/view/421climatic factorsramsperm
spellingShingle Damares Betega Pereira
André Torres Geraldo
Camila de Miranda e Silva Chaves
Célia Raquel Quirino
Mauro Sartori Bueno
Ricardo Lopes Dias da Costa
Effect of scrotal temperature on semen characteristics in Morada Nova rams
Boletim de Indústria Animal
climatic factors
ram
sperm
title Effect of scrotal temperature on semen characteristics in Morada Nova rams
title_full Effect of scrotal temperature on semen characteristics in Morada Nova rams
title_fullStr Effect of scrotal temperature on semen characteristics in Morada Nova rams
title_full_unstemmed Effect of scrotal temperature on semen characteristics in Morada Nova rams
title_short Effect of scrotal temperature on semen characteristics in Morada Nova rams
title_sort effect of scrotal temperature on semen characteristics in morada nova rams
topic climatic factors
ram
sperm
url http://10.153.18.28/index.php/bia/article/view/421
work_keys_str_mv AT damaresbetegapereira effectofscrotaltemperatureonsemencharacteristicsinmoradanovarams
AT andretorresgeraldo effectofscrotaltemperatureonsemencharacteristicsinmoradanovarams
AT camilademirandaesilvachaves effectofscrotaltemperatureonsemencharacteristicsinmoradanovarams
AT celiaraquelquirino effectofscrotaltemperatureonsemencharacteristicsinmoradanovarams
AT maurosartoribueno effectofscrotaltemperatureonsemencharacteristicsinmoradanovarams
AT ricardolopesdiasdacosta effectofscrotaltemperatureonsemencharacteristicsinmoradanovarams