The use of artificial insemination gun protective plastic sheath at the time of artificial insemination did not improve fertility of beef cattle

Abstract

A strict hygienic artificial insemination (AI) technique is critical to maximize reproductive
outcomes. The objective of this study was to evaluate the effect of AI gun protective plastic sheaths use
on AI pregnancy rates (AI-PR) in beef cattle. Angus cross beef cows (n=321) and Angus cross beef
heifers (n=430) were randomly assigned to one of two groups: with (TRT) or without (CON) the use of
disposable plastic sheath during the AI procedure. Accounting for estrus expression at or prior to AI
(P<0.01), the use of protective sheath neither in cows (sheath, 59.4% [95/160] vs. no sheath, 55.9%
[90/161]; P>0.1] nor in heifers (sheath, 58.3 [127/218] vs. no sheath, 56.7% [121/212]; P>0.1) improved
AI-PR. Both cows and heifers that expressed estrus at or prior to AI had greater AI-PR compared to that
did not express estrus (cows: estrus, 64.4% [116/180] vs. no estrus, 48.9 [69/141]; heifers: estrus, 64.6
[144/213] vs. no estrus, 50.2 [104/207]; P<0.01). In conclusion, carrying out a hygienic AI technique is
critical for AI success; however, the use of protective sheath did not improve reproductive outcomes in
beef cattle.