کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2394047 1101370 2006 16 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Exogenous leptin advances puberty in domestic hen
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم دامی و جانورشناسی
پیش نمایش صفحه اول مقاله
Exogenous leptin advances puberty in domestic hen
چکیده انگلیسی

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.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Domestic Animal Endocrinology - Volume 31, Issue 3, October 2006, Pages 211–226
نویسندگان
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