A sharp increase in sex ratio at birth in the Caucasus. Why? How?
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A field study on the reproductive efficiency of sex-sorted semen in Holstein heifers
Sex-sorted semen can increase the profitability of dairy cattle by producing offspring of the desired sex. The objective of the present study was to compare conception rate, stillbirth, calving difficulty and sex ratios from sexed and conventional semen in a commercial dairy herd in Isfahan province, Iran. Data were collected from April 2009 until December 2015 on 13,343 inseminations in 8,011 ...
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The present study was conducted to evaluate the effect of fish oil supplementation prior to mating on secondary sex ratio of pups (the proportion of males at birth) in bitches. Sixty five bitches (German Shepherd, n = 35; Husky, n = 30) were enrolled in the study. Bitches (140-150 days post-estrus) were given 2% per dry matter intake palm oil and fish oil in the control (n = 33) and treatment (...
متن کاملاستفاده از مواد اسپرم کش و غلبه بر حاملگی
The relation between periconceptional vaginal permicide use and sex ratio at birth, birth weight, and the frequency of congenital anomalies was examined in a cohort of 2,712 New York City obstetric patients, 149 of whom (5.5 per cent) became pregnant while using spermicides or had used spermicides before and after conception. Periconceptional spermicide use was not associated with any important...
متن کاملThe mystery of missing female children in the Caucasus: an analysis of sex ratios by birth order.
CONTEXT Official data on sex ratios at birth suggest a rise in sex-selective abortions in some post-Soviet states following the introduction of ultrasonography. However, questions remain about the validity of official data in these nations as well as whether the high sex ratios at birth are a statistical artifact. METHODS Trends in sex ratios at birth from 1985 to 2009 for 12 post-Soviet stat...
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Objective Selection of sperm for intra-cytoplasmic sperm injection (ICSI) is usually considered as the ultimate technique to alleviate male-factor infertility. In routine ICSI, selection is based on morphology and viability which does not necessarily preclude the chance injection of DNA-damaged or apoptotic sperm into the oocyte. Sperm with high negative surface electrical charge, named “Zeta p...
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