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Showing 1 to 6 of 6 for “"heifer fertility"”.
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Molecular phenotypes associated with heifer fertility
… relationship between many production traits and fertility. The large decrease in fertility that occurred as a result of these selection practices put a heavy burden on producers. Replacement heifer development is the third largest cost incurred by producers, behind feed and labor. Consequently, …
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Phenotypic and microbial influences on dairy heifer fertility and calf gut microbial development
… of the reproductive tract would influence heifer fertility and calf gut microbial development. The objectives of this dissertation were: 1) to examine differences in phenotypes related to reproductive physiology in virgin Holstein heifers based on outcome of first insemination, 2) to …
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Effect of pulmonary arterial pressure and precipitation on reproductive performance in Angus heifers in south central Wyoming
… of the commercial beef operation. However, fertility is affected by many physiological and environmental factors. Age and weight directly influence puberty in cattle, which is also influenced by nutrition. Many areas in the western United States where beef cattle are produced are arid …
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Genetic Parameters and Genetic Trends of Female Fertility in Icelandic Dairy Cattle
Fertility, represented by calving interval, has been included in the genetic evaluation of Icelandic dairy cattle since 1993. In spite of this an unfavourable genetic trend is seen and, recent implementation of test-day models for the genetic evaluation of milk production has changed the premise of …
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Relationships among heifer traits, early-life productive traits, and lifetime productivity within Angus and Simmental female cattle
… calfhood and early-life traits of females with fertility in the first two breeding seasons, and with calf production in the first, in three and in eleven years of life. These traits were used to develop prediction equations for fertility using logistic regression methodology. For productive …
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Development of a multi-breed heifer pregnancy genetic evaluation in beef cattle
Heifer fertility represents a primary influence on the profitability of a beef cow-calf enterprise. Reproductive rates determine the number of calves born and thus influence the amount of beef product produced at the commercial level driving income for cow-calf operators. Heifer fertility then is …