A retrospective cohort study on fertility in the Norwegian Coldblooded trotter after artificial insemination with cooled, shipped versus fresh extended semen

نویسندگان

  • Caroline Sorknes Haadem
  • Ane Nødtvedt
  • Wenche Farstad
  • Ragnar Thomassen
چکیده

BACKGROUND Pregnancy rates with cooled equine semen can be unsatisfactory and show great variation. Information about first cycle pregnancy rates and pregnancy rates per cycle are often lacking from publicly available records. This retrospective cohort study was performed to evaluate the fertility of the Norwegian Coldblooded trotter. The aim of the study was to compare the breeding results after insemination with fresh, extended with those of cooled, shipped semen among Norwegian Coldblooded trotter mares. First cycle pregnancy rate was the main parameter used to measure fertility. Stud-books were collected from four studs from the years 2006-2010. Statistical analyses were done in Stata using Chi square test and multivariable analyses where different models were compared based on Akaike's information criterion. RESULTS First cycle pregnancy rate, seasonal pregnancy rate and foaling rate all showed significant differences (P < 0.0001) when comparing mares inseminated at stud with mares inseminated with cooled, shipped semen, favoring artificial insemination (AI) at stud. First cycle pregnancy rate was 55.1 % for mares inseminated at stud with fresh extended semen and 42.2 % for mares inseminated with cooled shipped semen. The overall pregnancy rate per cycle was 84.4 % for AI at stud and 66.9 % for cooled, shipped semen. The parameters stud, mare age, number of inseminations within an estrus cycle and individual stallion were also investigated for influence on fertility. CONCLUSIONS Few retrospective studies include the parameter of first cycle pregnancy rates. Our study does not differ dramatically when comparing seasonal pregnancy rates and foaling rates with similar studies. Fertility parameters for the Norwegian Coldblooded trotter do not differ significantly from most other studies of Coldblooded mares and other mare breeds around the world. But the difference in fertility parameters between AI at stud to AI with cooled semen between our study and others, indicates that higher pregnancy rates in Norwegian Coldblooded trotter may be possible.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Supplementing Fatty Acids to Improve Sperm Characteristics

Artificial insemination via cooled or frozen-shipped semen allows more mares to be bred to a single stallion, but not all stallions produce semen capable of withstanding the cooling and freezing procedures. Aurich et al. (1996) estimated that cooled or frozen-shipped semen achieves < 75% of the pregnancy rates achieved with fresh semen. Some factors affecting the fertility rates of thawed semen...

متن کامل

Effect of cooling, storage, glycerolization and spermatozoal numbers on equine fertility.

The effects of cooling, storage, glycerolization and spermatozoal numbers on fertility were investigated utilizing three stallions and 72 mares. Semen was extended in a cream-gel extender and inseminated: a) within 1 hr (fresh) at 38 C, b) after cooling for 2 hr to 5 C, c) after cooling for 2 hr plus the addition of 7% (v/v) glycerol, and d) after cooling for 24 hours. Onehalf of the mares were...

متن کامل

Pregnancy Rates with Cooled Equine Semen Received in Private Practice

The equine shipped semen industry has developed and grown during the past few years, especially since the largest horse registry within the U.S., The American Quarter Horse Association, has recently sanctioned its use. However, a tremendous variation exists in the quality of shipped semen. This is due to factors ranging from the inherent ability of the stallion’s semen to withstand a particular...

متن کامل

An analysis of Selected Aspects of Sperm Quality in Fresh and Cooled-Storage Stallion Semen

This review summarises the most significant findings related to the issue of the quantitative and qualitative indicators of stallion ejaculates, its processing when producing chilled insemination doses and the possibility of influencing the individual steps of the entire process. Artificial insemination, with cooled-storage semen, is increasingly used in horse breeding because it offers many ad...

متن کامل

Factors influencing the success of an artificial insemination program in Florida goats

An artificial insemination (AI) program using cooled semen was evaluated over a 7-year period in Florida goats. The effect of the following variables on pregnancy rates was analysed: production system, year and season of AI, synchronisation treatment, bucks, AI technicians, semen deposition site, days in milk at AI, milk yield and parity. Animals were reared under field conditions on commercial...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره 57  شماره 

صفحات  -

تاریخ انتشار 2015