Male, female and management risk factors for non-return to service in Dutch mares

Factors Influencing the Popularity of Artificial Insemination of Mares in Europe

Simple Summary

The popularity of mare insemination as an element affecting the dynamic growth of breeding progress among horses in Europe is subject to various fluctuations. The success of this method of reproduction should be considered first of all in terms of the quality of semen available on the market, the types of semen storage technology, the profitability of its use resulting from the effectiveness of insemination with the selected type of semen, and factors affecting the success of artificial insemination. The purpose of this work was to present the factors determining the popularity of artificial insemination of mares in Europe. The presented statistics show that the popularity of the use of chilled semen has gradually increased in the group of sport mares, while in the group of breeding mares, the popularity of frozen semen has increased. In the remaining group of mares (not classified as sport or breeding), insemination with chilled semen was dominant. To talk about the success of artificial insemination of horses in Europe, it is necessary to look thoroughly at these aspects that affect the popularity of this reproduction biotechnology, and in particular to improve the quality of insemination doses.

Abstract

The purpose of this review was to analyze factors affecting the popularity of artificial insemination of mares in Europe in the context of sperm quality. Taking into account the prices of stallion semen on the world market, efficiency is important for the profitability of its use in artificial insemination programs in Europe. To increase the efficiency of a semen insemination facility, it is necessary to correctly and objectively assess the quality of semen. The available range of tools allows an effective evaluation of the potential fertility of a stallion. For several years, artificial insemination programs in Europe have been gaining popularity. However, the frequency of chilled or frozen semen use is still quite low. This is mainly due to the common, negative opinion about the effectiveness of the use of packaged insemination doses as opposed to natural insemination. Unfortunately, the quality of the semen offered often deviates from expectations, which results in unsatisfactory (and therefore unprofitable) pregnancy rates. This review presents the popularity structure of chilled and frozen semen use in European horse breeding as well as the current state of research on the effectiveness of semen production technology. It is shown that the popularity of using chilled semen in the artificial insemination of mares in Europe has been gradually increasing in the group of sport mares, while in the group of breeding mares, in recent years, frozen semen has been gaining popularity. In the remaining group of mares (not classified as sport or breeding), insemination with chilled semen has been dominant.

Efeito da idade sobre a fertilidade e perdas embrionárias de éguas inseminadas com sêmen asinino diluído e resfriado a 5ºC por 12 horas de armazenamento

Estudou-se o efeito da idade sobre a fertilidade de éguas inseminadas com sêmen asinino diluído, resfriado e armazenado. Os ciclos foram acompanhados por palpação transretal e rufiação, sendo as inseminações realizadas às terças, quintas e sábados, a partir da detecção de um folículo de 3,0 a 3,5cm de diâmetro, em um dos ovários, até a ovulação. O sêmen de cinco jumentos da raça Pêga foi diluído nos diluidores de leite em pó desnatado-glicose ou glicina-gema de ovo, resfriado a 5ºC e armazenado por 12 horas, sendo a dose inseminante de 400 x 106espermatozoides móveis (no momento da diluição final, pré-resfriamento). Os resultados de 195 ciclos estrais, referentes a 141 éguas, foram agrupados em classes, de acordo com a idade das éguas: 2,5 a 6 anos, 6,5 a 10 anos, 10,5 a 14 anos e 14,5 a 19 anos. As taxas de concepção, ao primeiro ciclo, foram de 68,42%, 50,75%, 46,88% e 52,17% e, após quatro ciclos, de 69,57%, 47,92%, 46,34% e 45,71% para as faixas etárias de 2,5 a 6, 6,5 a 10, 10,5 a 14 e 14,5 a 19 anos, respectivamente (P>0,05). A idade não teve efeito sobre a fertilidade das éguas inseminadas com sêmen asinino diluído e resfriado.

Efeito do número de inseminações artificiais sobre a fertilidade de éguas inseminadas com sêmen asinino diluído e resfriado a 5ºC por 12 horas de armazenamento

Estudou-se o efeito do número de inseminações sobre a fertilidade de éguas inseminadas com sêmen asinino diluído, resfriado e armazenado. Os ciclos foram acompanhados por palpação retal e rufiação, sendo as inseminações realizadas às terças, quintas e sábados (três vezes por semana), a partir da detecção de um folículo de 3,0 a 3,5cm de diâmetro, em um dos ovários, até a ovulação. O sêmen de cinco jumentos da raça Pêga foi diluído nos diluidores de leite em pó desnatado-glicose ou glicina-gema de ovo, resfriado a 5ºC e armazenado por 12 horas, sendo a dose inseminante de aproximadamente 400x10(6) espermatozoides móveis (no momento da diluição final, pré-resfriamento). De acordo com o número de inseminações artificiais (IA)/ciclo, os resultados de 195 ciclos, referentes a 140 éguas, foram agrupados em 1IA, 2IA e 3 ou mais IA. As taxas de concepção, ao primeiro ciclo, foram de 50,0%, 62,1% e de 41,0% e, após quatro ciclos, de 47,7%, 55,6% e de 42,9% para 1IA, 2IA e 3 ou mais IA, respectivamente (P>0,05). O número de IA/ciclo, utilizando sêmen asinino resfriado, não teve efeito sobre a fertilidade das éguas.

Factors influencing conception rates of Arab mares in Tunisia

In order to investigate the factors affecting the reproduction efficiency of Arab breeding mares in Tunisia, breeding data corresponding to 2340 mated cycles, over 5 years (from 2000 to 2004), from 555 mares offspring of 50 sires and bred with 17 stallions were analysed using a multivariate logistic regression. We chose logit link function and binomial distribution and we used log-likelihood-ratio (LL) and Wald tests (X(2)Wald) to test the mean values. The factors of variation included in the model were the year, the stallion, the age of the mare at mating, the sire and the category of the mare. Logistic regression results showed that age and sire affected both the overall conception rate and the first-cycle conception rate of the mares whilst category and stallion influenced only the overall conception rate. To our knowledge, this is the first study showing that the sire of the mare can affect both the first-cycle conception rate and the overall conception rate of the mares.