Date of Hatch and Day Length Affect Age at First Egg
نویسندگان
چکیده
منابع مشابه
Spread of hatch and delayed feed access affect post hatch performance of female broiler chicks up to day 5.
It is not rare that newly hatched chicks remain without feed for about 24 to 48 h before they are placed on farms due to a series of logistic operations. Furthermore, the spread in hatching time can also mount up to 30 to 48 h for late v. early hatchers. In other words, the practice is a complex combination of spread of hatch and delayed feed access. The present study was aimed to investigate t...
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Because of difficulties in data collection and analysis, in most breeds there have been limited ways to evaluate fertility in females on a between-herd basis. The objective of this study was to determine the heritabilities (direct and maternal) for CD (calving day) and AFC (age at first calving) in American Angus heifers and to evaluate the potential for using these traits in genetic improvemen...
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sities that were lower than initial densities (Fig. 2, Tab le 1). Assuming a similar extraction efficiency for the Washington State population, the general nature of the relationship between initial and final nematode densities on Washoe was similar to the Italian population. Tile final densities of J2 of the Italian populat ion were lower than the initial densities at all inoculum levels in th...
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ژورنال
عنوان ژورنال: Poultry Science
سال: 1946
ISSN: 0032-5791
DOI: 10.3382/ps.0250587