作为乳牛母牛的生殖表现指标的生殖器比率
Barbara Beci1, Mieke Van Eetvelde1, Louise Vanlommel1
1Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820, Merelbeke, Belgium.
Theriogenology
|July 23, 2023
概括
测量异位距离,特别是AGDv和AGR,可以预测乳牛母牛的生殖表现. 较短的AGDv和较小的AGR与更早的受孕和更高的怀孕率有关,这表明它们可以用作生育指标.
科学领域:
- 生殖生物学 生殖生物学
- 动物科学动物科学
- 兽医医学 兽医医学 兽医医学
背景情况:
- 生殖器的距离 (AGD) 是一个公认的标志物,用于产前的雄激素暴露和跨物种的生育能力.
- 在乳牛中,从阴茎到阴蒂底部 (AGDc) 的距离是标准的,但从阴茎到阴茎的距离 (AGDv) 和阴茎比率 (AGR) 是用于生育预测的.
研究的目的:
- 评估AGDv和AGR作为乳牛母牛的生殖表现指标的潜力.
- 为了研究AGDv,AGDc和其他体型测量在雌牛之间的关系.
主要方法:
- 分析了来自656只荷尔斯坦弗里西亚公牛 (年龄13.5±1.08个月) 的数据.
- 测量AGDv,AGDc,AGR和其他身体参数.
- 应用线性回归和ROC曲线分析来评估与生育特征的关联.
主要成果:
- AGDv和AGR与生殖表现呈负相关性;较短的AGDv和较小的AGR与第一次人工授精 (AI) 和受孕时的年龄较小相关.
- AGDv被确定为怀孕到第一个AI的关键指标,值为65.3毫米.
- 具有AGDv < 65.3毫米的母牛在第一个AI时怀孕的几率明显更高 (63%的增加).
- 一个59.6%的AGR值表明,在第一个AI时怀孕的几率更高 (44%的增加).
- AGD测量在很大程度上与其他身体测量无关,这表明产前决定.
结论:
- AGDv和AGR显示出作为预测乳牛母牛繁殖成功的非侵入性指标的前景.
- 建议在未来的生殖研究中测量AGDc和AGDv.
- 缺乏与身体尺寸的相关性支持了AGD主要是产前确定的假设.
相关概念视频
01:24Testing a Claim about Population Proportion
3.4K
A complete procedure for testing a claim about a population proportion is provided here.
There are two methods of testing a claim about a population proportion: (1) Using the sample proportion from the data where a binomial distribution is approximated to the normal distribution and (2) Using the binomial probabilities calculated from the data.
The first method uses normal distribution as an approximation to the binomial distribution. The requirements are as follows: sample size is large...
There are two methods of testing a claim about a population proportion: (1) Using the sample proportion from the data where a binomial distribution is approximated to the normal distribution and (2) Using the binomial probabilities calculated from the data.
The first method uses normal distribution as an approximation to the binomial distribution. The requirements are as follows: sample size is large...
3.4K
02:45The Ratio of X Chromosome to Autosomes
8.6K
In most organisms, sex is determined by the ratio of X and Y chromosomes. However, in some organisms, such as Drosophila and C.elegans, sex is determined by the ratio of the number of X chromosomes to the number of sets of autosomes. The Y chromosome in Drosophila is active but does not determine sex. It contains genes responsible for the production of sperms in adult flies.
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female...
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female...
8.6K
02:46Chi-square Analysis
38.4K
The chi-square test is a statistical hypothesis test. It is used to check whether there is a significant difference between an expected value and an observed value. In the context of genetics, it enables us to either accept or reject a hypothesis, based on how much the observed values deviate from the expected values.
The chi-square test was developed by Pearson in 1990.
The first step of performing a Chi-square analysis is to establish a null hypothesis, which assumes that there is no real...
The chi-square test was developed by Pearson in 1990.
The first step of performing a Chi-square analysis is to establish a null hypothesis, which assumes that there is no real...
38.4K