Data/hora: 23/09/2024 23:33:07

Biblioteca(s): 	Embrapa Pantanal.	
Data corrente: 	09/04/1996	
Data da última atualização: 	03/04/2017	
Autoria: 	CHENOWETH, P. J.; RISCO, C. A.; LARSEN, R. E.; VELEZ, J.; TRAN, T.; CHASE JUNIOR, C. C.	
Título: 	Effects of dietary gossypol on aspects of semen quality, sperm morphology and sperm production in young Brahman bulls.	
Ano de publicação: 	1994	
Fonte/Imprenta: 	Theriogenology, v.42, n.1, p.1-13, 1994.	
Idioma: 	Inglês	
Conteúdo: 	Eight young reproductively normal Brahman bulls (average age and bodyweight 20 monts and 500 kg, respectively) received either cottonseed meal delivering 8.2 g free gossypol/bull/d (treatment group, n=4) or soybean meal (control group, n=4) for 12 wk. After adjustment (1 wk), weekly procedures (11 wk) included blood collection, scrotal circumference measurement and electro-ejaculation. Semen assessment included sperm motility, percentage of live spermatozoa, general sperm morphology (using brighfield microscopy), and midpiece morphology (using DIC microscopy). After sacrifice (Week 12), sperm production rates (daily and per gram testicular parenchyma) were determined. Treated bulls did not differ from controls in scrotal circumference or the percentage of live spermatozoa. Sperm motility differed at Weeks 9 (P<0.05), 10 and 11 (both P=0.06). Treated bulls had fewer normal spermatozoa at weeks 5 (P<0.05), 6 (P<0.01) and 7 thru 11 (P<0.001). Beginning from Week 3, treated bulls showed an increased proportion of sperm midpiece abnormalities (P<0.05) which stabilizewd at 52 to 62.5% between Weeks 5 and 11 (P<0.01 or P<0.001). Treated bulls also had lower sperm production than untreated bulls, both on a daily (P<0.01) and per gram testicular parenchyma (P<0.001) basis. A cottonseed supplement providing 8.2 g of free gossypol per bull per day had adverse effects upon both sperm morphology and spermatogenesis in young Brahman bulls, with the former being first evident within 3 to 4 weeks of feeding of cottonseed meal.	
Palavras-Chave: 	Bull; Production; Reprodution.	
Thesagro: 	Animal; Produção; Reprodução; Touro.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Pantanal (CPAP)	
Exemplares: 	CPAP - (31477-1) - ADD - SP - PP - SP14771 -  - 14771 - DIS