Multiple superovulations in N'Dama heifers.

Area of Science:

• Veterinary Science
• Animal Reproduction
• Tuberculosis Research

Background:

• N'Dama cattle are a vital breed in tropical regions, often susceptible to diseases like trypanosomiasis.
• Improving reproductive efficiency in N'Dama cattle is crucial for sustainable livestock production.
• Embryo transfer technology (ETT) offers a potential method for genetic improvement in cattle.

Purpose of the Study:

• To evaluate the efficacy of multiple superovulations using follicle-stimulating hormone (FSH) in N'Dama heifers.
• To assess embryo production and quality during repeated superovulation cycles.
• To determine the pregnancy rate following embryo transfer into recipient cows.

Main Methods:

• Five N'Dama heifers underwent six superovulation treatments each with FSH-P (Folltropin).
• Superovulations were performed during experimental Trypanosoma congolense infections.
• Embryos were collected via uterine flushing and transferred to Boran (Bos indicus) recipients.

Main Results:

• 80% of superovulations resulted in a good ovarian response, yielding an average of 2.7 embryos per successful attempt.
• Peak embryo production and quality occurred around the third and fourth superovulations.
• A 50.9% overall pregnancy rate was achieved in recipient cows.
• Heifer uterine size increased significantly, complicating embryo collection after the third superovulation.

Conclusions:

• Embryo transfer technology is a valuable breeding tool for N'Dama heifers.
• Multiple superovulations can be successfully performed in N'Dama heifers, even with concurrent disease challenges.
• Reproductive management strategies should consider potential declines in embryo quality with repeated superovulations.