Some Factors Affecting Age at Puberty in Holstein-Friesian Heifers
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چکیده
منابع مشابه
Photoperiod influences age at puberty of heifers.
Two experiments were conducted to determine if exposure of prepubertal heifers to supplemental lighting hastens the onset of puberty. In Exp. 1, 16 heifers were paired according to birth date (April 21 to July 4) and assigned randomly to exposure to either 18 h light/d (L) or natural photoperiods (N) from 22 wk of age until puberty. Twenty-two heifers in Exp. 2, born between February 27 and Mar...
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متن کاملInductions of superovulation using several FSH regimens in Holstein-Friesian heifers.
Note Eighty-three Holstein-Friesian virgin heifers were randomly divided into four groups and superovulated with one of the four FSH regimens as follows : Group I) twice daily injections of a constant dose of 5 mg of FSH for a period of 4 days, giving a total dose of 40 mg in 8 fractions ; Group II) as in Group I with additional 5 mg of FSH on the 5th day, giving a total dose of 45 mg ; Group I...
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ژورنال
عنوان ژورنال: Journal of Dairy Science
سال: 1954
ISSN: 0022-0302
DOI: 10.3168/jds.s0022-0302(54)91248-5