RESUMO

Thirty healthy Sohagi ram lambs with an average age of 188.6±7.3 days were used to study the effect of pre-pubertal growth rate on some physiological parameters and sexual behavioral patterns at puberty. Ram lambs were divided into three groups (10 animals per each group) according to the previous growth rate until 6 months of age. Groups were marked as fast, medium and slow growing. Animal groups were housed in closed barns with access to an open area. Results showed that age and weight of ram lambs at puberty were significantly affected (P<0.05) by the pre-pubertal growth rate. Ram lambs in the fast growing group were reached to onset puberty firstly at 272.6 days with body weight (BW) 37.1 kg on average then ram lambs in medium group (284.8 days with BW 32.7 kg), while ram lambs in slow growing group were the last (314.1 days with BW 32.5 kg). Blood testosterone concentration at puberty was not significantly different among growing groups (1.494± 0.03 ng/ml on average, ranged from 1.287 to 1.902 ng/ml). Testes measurements from 6 months of age until puberty show that ram lambs in fast growing group had the highest values of testes length, circumference and volume followed by those in medium and slow growing group. Sexual behavioral observation showed that flehmen and mounting behavior were significantly higher for ram lambs in fast growing group (5.63 and 6.75 number/12h) than slow growing group (4.25 and 5.38 number/12h) while in medium growing group were intermediate (4.88 and 5.88 number/12h). From these findings, could be concluded that age, weight and sexual behavioral patterns of Sohagi ram lambs at puberty were affected by pre-pubertal growth rate, and the breeders should strive to achieve good growth rates for their lambs before puberty which led to improving reproductive performance.

RESUMO

Abstract Thirty healthy Sohagi ram lambs with an average age of 188.6±7.3 days were used to study the effect of pre-pubertal growth rate on some physiological parameters and sexual behavioral patterns at puberty. Ram lambs were divided into three groups (10 animals per each group) according to the previous growth rate until 6 months of age. Groups were marked as fast, medium and slow growing. Animal groups were housed in closed barns with access to an open area. Results showed that age and weight of ram lambs at puberty were significantly affected (P<0.05) by the pre-pubertal growth rate. Ram lambs in the fast growing group were reached to onset puberty firstly at 272.6 days with body weight (BW) 37.1 kg on average then ram lambs in medium group (284.8 days with BW 32.7 kg), while ram lambs in slow growing group were the last (314.1 days with BW 32.5 kg). Blood‎ testosterone‎ concentration at puberty was not significantly different among growing groups (1.494± 0.03 ng/ml on average, ranged from 1.287 to 1.902 ng/ml). Testes measurements from 6 months of age until puberty show that ram lambs in fast growing group had the highest values of testes length, circumference and volume followed by those in medium and slow growing group. Sexual behavioral observation showed that flehmen and mounting behavior were significantly higher for ram lambs in fast growing group (5.63 and 6.75 number/12h) than slow growing group (4.25 and 5.38 number/12h) while in medium growing group were intermediate (4.88 and 5.88 number/12h). From these findings, could be concluded that age, weight and sexual behavioral patterns of Sohagi ram lambs at puberty were affected by pre-pubertal growth rate, and the breeders should strive to achieve good growth rates for their lambs before puberty which led to improving reproductive performance.

RESUMO

The present work evaluated the effects of feeding graded levels of whole cottonseed on reproductive parameters of Red Sokoto bucks. Twenty Red Sokoto bucks were used for the experiment. After a 14-day pre-treatment period, bucks were assigned for 90 days to one of four isonitrogeneous treatments: control (diet A); 0 mg kg-1of total gossypol, (diet B); 15% mg kg-1of total gossypol, (diet C); 30% mg kg-1of total gossypol and (diet D); 45% mg kg-1of total gossypol.The mean percentage sperm gross motility was significantly (p 0.05)different among treatment groups. Semen colour of the bucks in the control group was majorly creamy, in group C (30% WCS) and B (15% WCS) creamy to milky and group D (45% WCS) colourless. The mean semen volume was significantly (p < 0.05) higher in groupsC and A compared to group D (45% WCS) at days 60, 75 and 90. The mean semen concentration was significantly (p < 0.05) lower in group D (45% WCS) when compared to group A (control) at days 30, 45, 60, 75 and 90. Group A (control) bucks had significantly (p < 0.05) higher percentage live sperm compared to those in group D (45% WCS) at days 45, 60, 75 and 90. Mean Sperm morphological abnormalities including detached head, free tail curved tail and midpiece droplets were significantly (p < 0.05) higher in group D (45%) than in group A (Control) at day 15 (for free tails) and day 90 (for all). Testicular and epididymal sperm reserves were higher in animals supplemented with up to 30% whole cottonseed.In conclusion, feeding bucks above 30% WCS resulted in more deleterious effects on the semen characteristics and testicular profile.

Assuntos

RESUMO

Thirty healthy Sohagi ram lambs with an average age of 188.6±7.3 days were used to study the effect of pre-pubertal growth rate on some physiological parameters and sexual behavioral patterns at puberty. Ram lambs were divided into three groups (10 animals per each group) according to the previous growth rate until 6 months of age. Groups were marked as fast, medium and slow growing. Animal groups were housed in closed barns with access to an open area. Results showed that age and weight of ram lambs at puberty were significantly affected (P<0.05) by the pre-pubertal growth rate. Ram lambs in the fast growing group were reached to onset puberty firstly at 272.6 days with body weight (BW) 37.1 kg on average then ram lambs in medium group (284.8 days with BW 32.7 kg), while ram lambs in slow growing group were the last (314.1 days with BW 32.5 kg). Blood‎ testosterone‎ concentration at puberty was not significantly different among growing groups (1.494± 0.03 ng/ml on average, ranged from 1.287 to 1.902 ng/ml). Testes measurements from 6 months of age until puberty show that ram lambs in fast growing group had the highest values of testes length, circumference and volume followed by those in medium and slow growing group. Sexual behavioral observation showed that flehmen and mounting behavior were significantly higher for ram lambs in fast growing group (5.63 and 6.75 number/12h) than slow growing group (4.25 and 5.38 number/12h) while in medium growing group were intermediate (4.88 and 5.88 number/12h). From these findings, could be concluded that age, weight and sexual behavioral patterns of Sohagi ram lambs at puberty were affected by pre-pubertal growth rate, and the breeders should strive to achieve good growth rates for their lambs before puberty which led to improving reproductive performance.(AU)

Assuntos

RESUMO

The present work evaluated the effects of feeding graded levels of whole cottonseed on reproductive parameters of Red Sokoto bucks. Twenty Red Sokoto bucks were used for the experiment. After a 14-day pre-treatment period, bucks were assigned for 90 days to one of four isonitrogeneous treatments: control (diet A); 0 mg kg-1of total gossypol, (diet B); 15% mg kg-1of total gossypol, (diet C); 30% mg kg-1of total gossypol and (diet D); 45% mg kg-1of total gossypol.The mean percentage sperm gross motility was significantly (p < 0.05) lower in group D (45% WCS) compared to groups C (30% WCS) and A (control) at days 60, 75 and 90. The mean semen pH and reaction time were not significantly (p > 0.05)different among treatment groups. Semen colour of the bucks in the control group was majorly creamy, in group C (30% WCS) and B (15% WCS) creamy to milky and group D (45% WCS) colourless. The mean semen volume was significantly (p < 0.05) higher in groupsC and A compared to group D (45% WCS) at days 60, 75 and 90. The mean semen concentration was significantly (p < 0.05) lower in group D (45% WCS) when compared to group A (control) at days 30, 45, 60, 75 and 90. Group A (control) bucks had significantly (p < 0.05) higher percentage live sperm compared to those in group D (45% WCS) at days 45, 60, 75 and 90. Mean Sperm morphological abnormalities including detached head, free tail curved tail and midpiece droplets were significantly (p < 0.05) higher in group D (45%) than in group A (Control) at day 15 (for free tails) and day 90 (for all). Testicular and epididymal sperm reserves were higher in animals supplemented with up to 30% whole cottonseed.In conclusion, feeding bucks above 30% WCS resulted in more deleterious effects on the semen characteristics and testicular profile.(AU)

Assuntos

RESUMO

The study of gonadal development improves the understanding of factors that can influence the reproductive development process. This study aims to characterize bovine fetal testicular development and the testosterone level in the Nellore breed. For the study, 162 bovine fetuses aged between 3 and 8 months were collected from Nellore cows at a local abattoir. The fetal age was estimated by DP=8.4+0.087L+5.46?L, where DP is the estimated pregnancy day and L represents fetal length. The fetal gonadal weight (g), width (cm), and thickness (cm) were measured. Thereafter, the gonads were submitted to classic histology processes in 3-µm-thick slices cut at 210 µm intervals. The Sertoli cells, Leydig cells, and germ cells were counted. Blood samples were collected from umbilical cords for testosterone levels. The data were analyzed using the Spearman correlation test followed by Principal Component Analysis and one-way ANOVA to compare the averages between months. The testicular weight and volume were found to have a positive correlation with the numbers of Sertoli cells (r = 0.84; p 0.0001 and r = 0.92; p 0.0001, respectively), Leydig cells (r = 0.80; p 0.0001 and r = 0.90; p 0.0001, respectively), and germ cells (r = 0.84; p 0.0001 and r = 0.93; p 0.0001, respectively) and to be negatively correlated with testosterone plasmatic concentration (r = -0.31; p = 0.0001 andr = -0.22; p = 0.006, respectively) during pregnancy. After the fifth month, the numbers of Sertolicells, Leydig cells and germ cells differed (p < 0.0001) from the following gestational months. Thehighest testosterone concentration (p = 0.007) was observed in the fifth month of gestation and wasfollowed by a concentration decrease in the seventh and eighth months. The increase in cell quantitywas responsible for the increase in testicular weight and volume during fetal development. On the otherhand...(AU)

O estudo do desenvolvimento gonadal melhora o entendimento dos fatores que podem influenciar o processo de desenvolvimento reprodutivo. Esse estudo objetivou caracterizar o desenvolvimento testicular bovino e os níveis de testosterona na raça Nelore. Para o estudo, 162 fetos bovinos com idade entre 3 e 8 meses foram coletados de vacas Nelore em frigorífico local. A idade fetal foi estimada pela fórmula DP=8.4+0.087L+5.46?L, onde DP corresponde ao dia estimado de gestação e L representa o comprimento fetal. Foram medidos o peso gonadal fetal (g), a largura (cm) e a espessura (cm). Após as mensurações, as gônadas foram submetidas ao processamento histológico clássico, sendo utilizadas para elaboração das lâminas cortes com 3 µm de espessura com intervalos entre cortes de 210 µm. As células de Sertoli, Leydig e germinativas foram contadas. Amostras de sangue foram coletadas do cordão umbilical para quantificação dos níveis de testosterona. Os dados foram analisados utilizando a correlação de Spearman seguida pela análise de componentes principais, sendo o comparativo de médias entre os meses realizados utilizando o one-way ANOVA. O peso e o volume testicular apresentaram correlação positiva com o número de células de Sertoli (r = 0,84; p 0,0001 e r = 0,92; p 0,0001, respectivamente), células de Leydig (r = 0,80; p 0,0001 e r = 0,90; p 0,0001, respectivamente), porém foramnegativamente correlacionados com a concentração plasmática de testosterona (r = -0,31; p = 0,0001e r = -0,22; p = 0,006, respectivamente) durante a gestação. Após o quinto mês, o número de célulasde Sertoli, de Leydig e germinativas diferiram (p < 0,0001) dos meses seguintes de gestação. A maiorconcentração de testosterona encontrada (p < 0,007) foi observada no quinto mês de gestação, sendoseguida por uma diminuição entre o sétimo e oitavo mês. O aumento na quantidade de células duranteo desenvolvimento fetal foi o responsável pelo aumento do peso e volume testicular...(AU)

Assuntos

RESUMO

The study of gonadal development improves the understanding of factors that can influence the reproductive development process. This study aims to characterize bovine fetal testicular development and the testosterone level in the Nellore breed. For the study, 162 bovine fetuses aged between 3 and 8 months were collected from Nellore cows at a local abattoir. The fetal age was estimated by DP=8.4+0.087L+5.46?L, where DP is the estimated pregnancy day and L represents fetal length. The fetal gonadal weight (g), width (cm), and thickness (cm) were measured. Thereafter, the gonads were submitted to classic histology processes in 3-µm-thick slices cut at 210 µm intervals. The Sertoli cells, Leydig cells, and germ cells were counted. Blood samples were collected from umbilical cords for testosterone levels. The data were analyzed using the Spearman correlation test followed by Principal Component Analysis and one-way ANOVA to compare the averages between months. The testicular weight and volume were found to have a positive correlation with the numbers of Sertoli cells (r = 0.84; p 0.0001 and r = 0.92; p 0.0001, respectively), Leydig cells (r = 0.80; p 0.0001 and r = 0.90; p 0.0001, respectively), and germ cells (r = 0.84; p 0.0001 and r = 0.93; p 0.0001, respectively) and to be negatively correlated with testosterone plasmatic concentration (r = -0.31; p = 0.0001 andr = -0.22; p = 0.006, respectively) during pregnancy. After the fifth month, the numbers of Sertolicells, Leydig cells and germ cells differed (p < 0.0001) from the following gestational months. Thehighest testosterone concentration (p = 0.007) was observed in the fifth month of gestation and wasfollowed by a concentration decrease in the seventh and eighth months. The increase in cell quantitywas responsible for the increase in testicular weight and volume during fetal development. On the otherhand...

O estudo do desenvolvimento gonadal melhora o entendimento dos fatores que podem influenciar o processo de desenvolvimento reprodutivo. Esse estudo objetivou caracterizar o desenvolvimento testicular bovino e os níveis de testosterona na raça Nelore. Para o estudo, 162 fetos bovinos com idade entre 3 e 8 meses foram coletados de vacas Nelore em frigorífico local. A idade fetal foi estimada pela fórmula DP=8.4+0.087L+5.46?L, onde DP corresponde ao dia estimado de gestação e L representa o comprimento fetal. Foram medidos o peso gonadal fetal (g), a largura (cm) e a espessura (cm). Após as mensurações, as gônadas foram submetidas ao processamento histológico clássico, sendo utilizadas para elaboração das lâminas cortes com 3 µm de espessura com intervalos entre cortes de 210 µm. As células de Sertoli, Leydig e germinativas foram contadas. Amostras de sangue foram coletadas do cordão umbilical para quantificação dos níveis de testosterona. Os dados foram analisados utilizando a correlação de Spearman seguida pela análise de componentes principais, sendo o comparativo de médias entre os meses realizados utilizando o one-way ANOVA. O peso e o volume testicular apresentaram correlação positiva com o número de células de Sertoli (r = 0,84; p 0,0001 e r = 0,92; p 0,0001, respectivamente), células de Leydig (r = 0,80; p 0,0001 e r = 0,90; p 0,0001, respectivamente), porém foramnegativamente correlacionados com a concentração plasmática de testosterona (r = -0,31; p = 0,0001e r = -0,22; p = 0,006, respectivamente) durante a gestação. Após o quinto mês, o número de célulasde Sertoli, de Leydig e germinativas diferiram (p < 0,0001) dos meses seguintes de gestação. A maiorconcentração de testosterona encontrada (p < 0,007) foi observada no quinto mês de gestação, sendoseguida por uma diminuição entre o sétimo e oitavo mês. O aumento na quantidade de células duranteo desenvolvimento fetal foi o responsável pelo aumento do peso e volume testicular...

Assuntos

RESUMO

The study of gonadal development improves the understanding of factors that can influence the reproductive development process. This study aims to characterize bovine fetal testicular development and the testosterone level in the Nellore breed. For the study, 162 bovine fetuses aged between 3 and 8 months were collected from Nellore cows at a local abattoir. The fetal age was estimated by DP=8.4+0.087L+5.46?L, where DP is the estimated pregnancy day and L represents fetal length. The fetal gonadal weight (g), width (cm), and thickness (cm) were measured. Thereafter, the gonads were submitted to classic histology processes in 3-µm-thick slices cut at 210 µm intervals. The Sertoli cells, Leydig cells, and germ cells were counted. Blood samples were collected from umbilical cords for testosterone levels. The data were analyzed using the Spearman correlation test followed by Principal Component Analysis and one-way ANOVA to compare the averages between months. The testicular weight and volume were found to have a positive correlation with the numbers of Sertoli cells (r = 0.84; p 0.0001 and r = 0.92; p 0.0001, respectively), Leydig cells (r = 0.80; p 0.0001 and r = 0.90; p 0.0001, respectively), and germ cells (r = 0.84; p 0.0001 and r = 0.93; p 0.0001, respectively) and to be negatively correlated with testosterone plasmatic concentration (r = -0.31;

O estudo do desenvolvimento gonadal melhora o entendimento dos fatores que podem influenciar o processo de desenvolvimento reprodutivo. Esse estudo objetivou caracterizar o desenvolvimento testicular bovino e os níveis de testosterona na raça Nelore. Para o estudo, 162 fetos bovinos com idade entre 3 e 8 meses foram coletados de vacas Nelore em frigorífico local. A idade fetal foi estimada pela fórmula DP=8.4+0.087L+5.46?L, onde DP corresponde ao dia estimado de gestação e L representa o comprimento fetal. Foram medidos o peso gonadal fetal (g), a largura (cm) e a espessura (cm). Após as mensurações, as gônadas foram submetidas ao processamento histológico clássico, sendo utilizadas para elaboração das lâminas cortes com 3 µm de espessura com intervalos entre cortes de 210 µm. As células de Sertoli, Leydig e germinativas foram contadas. Amostras de sangue foram coletadas do cordão umbilical para quantificação dos níveis de testosterona. Os dados foram analisados utilizando a correlação de Spearman seguida pela análise de componentes principais, sendo o comparativo de médias entre os meses realizados utilizando o one-way ANOVA. O peso e o volume testicular apresentaram correlação positiva com o número de células de Sertoli (r = 0,84; p 0,0001 e r = 0,92; p 0,0001, respectivamente), células de Leydig (r = 0,80; p 0,0001 e r = 0,90; p 0,0001, respectivamente),

RESUMO

The study of gonadal development improves the understanding of factors that can influence the reproductive development process. This study aims to characterize bovine fetal testicular development and the testosterone level in the Nellore breed. For the study, 162 bovine fetuses aged between 3 and 8 months were collected from Nellore cows at a local abattoir. The fetal age was estimated by DP=8.4+0.087L+5.46?L, where DP is the estimated pregnancy day and L represents fetal length. The fetal gonadal weight (g), width (cm), and thickness (cm) were measured. Thereafter, the gonads were submitted to classic histology processes in 3-µm-thick slices cut at 210 µm intervals. The Sertoli cells, Leydig cells, and germ cells were counted. Blood samples were collected from umbilical cords for testosterone levels. The data were analyzed using the Spearman correlation test followed by Principal Component Analysis and one-way ANOVA to compare the averages between months. The testicular weight and volume were found to have a positive correlation with the numbers of Sertoli cells (r = 0.84; p 0.0001 and r = 0.92; p 0.0001, respectively), Leydig cells (r = 0.80; p 0.0001 and r = 0.90; p 0.0001, respectively), and germ cells (r = 0.84; p 0.0001 and r = 0.93; p 0.0001, respectively) and to be negatively correlated with testosterone plasmatic concentration (r = -0.31;

O estudo do desenvolvimento gonadal melhora o entendimento dos fatores que podem influenciar o processo de desenvolvimento reprodutivo. Esse estudo objetivou caracterizar o desenvolvimento testicular bovino e os níveis de testosterona na raça Nelore. Para o estudo, 162 fetos bovinos com idade entre 3 e 8 meses foram coletados de vacas Nelore em frigorífico local. A idade fetal foi estimada pela fórmula DP=8.4+0.087L+5.46?L, onde DP corresponde ao dia estimado de gestação e L representa o comprimento fetal. Foram medidos o peso gonadal fetal (g), a largura (cm) e a espessura (cm). Após as mensurações, as gônadas foram submetidas ao processamento histológico clássico, sendo utilizadas para elaboração das lâminas cortes com 3 µm de espessura com intervalos entre cortes de 210 µm. As células de Sertoli, Leydig e germinativas foram contadas. Amostras de sangue foram coletadas do cordão umbilical para quantificação dos níveis de testosterona. Os dados foram analisados utilizando a correlação de Spearman seguida pela análise de componentes principais, sendo o comparativo de médias entre os meses realizados utilizando o one-way ANOVA. O peso e o volume testicular apresentaram correlação positiva com o número de células de Sertoli (r = 0,84; p 0,0001 e r = 0,92; p 0,0001, respectivamente), células de Leydig (r = 0,80; p 0,0001 e r = 0,90; p 0,0001, respectivamente),