Data/hora: 01/06/2024 13:35:58

Biblioteca(s): 	Embrapa Caprinos e Ovinos.	
Data corrente: 	25/11/2002	
Data da última atualização: 	25/11/2002	
Autoria: 	TOKUDA, T.; MATSUI, T.; YANO, H.	
Título: 	Effects of light and food on plasma leptin concentrations in ewes.	
Ano de publicação: 	2000	
Fonte/Imprenta: 	Animal Science, v. 71, n. 2, p. 235-242, 2000.	
Idioma: 	Inglês	
Conteúdo: 	Plasma leptin concentration shows pulsatility and diurnal rhythm in humans. However, there are few reports concerning the 24-h profile of circulating leptin levels in ruminants. Five crossbred ewes were housed in metabolism cages under a l-h light-dark cycle. The ewes were offered alfalfa hay daily to meet their energy requirement. Blood samples were collected at 15-min intervals for 24 h. Plasma leptin concentrations were determined using a radioimmunoassay and the profile of plasma leptin levels was analysed by the PULSAR algorithmic program for detecting pulse. Plasma leptin concentration changed in a pulsatile fashion. The mean leptin concentration was 2.93 ng/ml. The mean pulse frequency was 4.8 pulses per day and the mean pulse amplitude was 0.67 ng/ml with an average pulse length of 1:13 h. Plasma leptin leveI was not offected by feeding or lighting cycle. These results indicate that plasma leptin level in sheep shows pulsatility but diurnal rhythm is not exhibited. 

Palavras-Chave: 	Concentração plasmática; Variação diurna.	
Thesagro: 	Hormônio; Ovelha; Ovino.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Caprinos e Ovinos (CNPC)	
Exemplares: 	CNPC - (15150-1) - ADC - AP - -- -  -  - v.71, n. 2 - DIS