TY - JOUR
T1 - Exogenous leptin advances puberty in domestic hen
AU - Paczoska-Eliasiewicz, Helena Elzbieta
AU - Proszkowiec-Weglarz, Monika
AU - Proudman, John
AU - Jacek, Tomasz
AU - Mika, Maria
AU - Sechman, Andrzej
AU - Rzasa, Janusz
AU - Gertler, Arieh
PY - 2006/10
Y1 - 2006/10
N2 - The present study was undertaken to examine the effect of recombinant chicken leptin administered to fed ad libitum and feed-restricted immature chickens of a layer strain on ovarian development and the timing of sexual maturity. In the first experiment 11-week-old pullets (77 days of age) fed ad libitum were injected daily with leptin at four dose levels (4, 16, 64 and 256 μg/kg body weight) until sexual maturity (lay of the first egg). Leptin treatment at the highest dose significantly (P < 0.05) advanced the onset of puberty (day 116.3 ± 1.0) in comparison to controls (day 121.3 ± 1.2). The rises of luteinizing hormone, estradiol and progesterone in blood plasma were also advanced by leptin treatment. In the second experiment, both full-fed and feed-restricted pullets (79 days of age) were injected daily with leptin (256 μg/kg body weight). In birds fed ad libitum, exogenous leptin again significantly (P < 0.05) advanced first ovipostion (day 118.4 ± 1.4 versus day 124.4 ± 1.7), while abolishing the significant (P < 0.05) delay caused by feed restriction (day 131.5 ± 1.6) and restoring the normal onset of sexual maturity (day 125.7 ± 1.6). Analysis of the ovaries in 106-day-old pullets revealed that leptin injections advanced follicular development, particularly in birds fed ad libitum, and significantly (P < 0.01) reduced follicular apoptosis both in full-fed and feed-restricted birds. In conclusion, we have shown that in female chickens exogenous leptin advances the onset of puberty by attenuation of ovarian apoptosis and enhancement of folliculogenesis.
AB - The present study was undertaken to examine the effect of recombinant chicken leptin administered to fed ad libitum and feed-restricted immature chickens of a layer strain on ovarian development and the timing of sexual maturity. In the first experiment 11-week-old pullets (77 days of age) fed ad libitum were injected daily with leptin at four dose levels (4, 16, 64 and 256 μg/kg body weight) until sexual maturity (lay of the first egg). Leptin treatment at the highest dose significantly (P < 0.05) advanced the onset of puberty (day 116.3 ± 1.0) in comparison to controls (day 121.3 ± 1.2). The rises of luteinizing hormone, estradiol and progesterone in blood plasma were also advanced by leptin treatment. In the second experiment, both full-fed and feed-restricted pullets (79 days of age) were injected daily with leptin (256 μg/kg body weight). In birds fed ad libitum, exogenous leptin again significantly (P < 0.05) advanced first ovipostion (day 118.4 ± 1.4 versus day 124.4 ± 1.7), while abolishing the significant (P < 0.05) delay caused by feed restriction (day 131.5 ± 1.6) and restoring the normal onset of sexual maturity (day 125.7 ± 1.6). Analysis of the ovaries in 106-day-old pullets revealed that leptin injections advanced follicular development, particularly in birds fed ad libitum, and significantly (P < 0.01) reduced follicular apoptosis both in full-fed and feed-restricted birds. In conclusion, we have shown that in female chickens exogenous leptin advances the onset of puberty by attenuation of ovarian apoptosis and enhancement of folliculogenesis.
KW - Apoptosis
KW - Chicken
KW - Follicular development
KW - Leptin
KW - Ovary
KW - Puberty
UR - http://www.scopus.com/inward/record.url?scp=33748600950&partnerID=8YFLogxK
U2 - 10.1016/j.domaniend.2005.10.005
DO - 10.1016/j.domaniend.2005.10.005
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C2 - 16303278
AN - SCOPUS:33748600950
SN - 0739-7240
VL - 31
SP - 211
EP - 226
JO - Domestic Animal Endocrinology
JF - Domestic Animal Endocrinology
IS - 3
ER -