Received: 23 May 2019
Accepted: 14 September 2019
First Online: 30 September 2019
Compliance with Ethical Standards
: The authors declare that they have no competing interests.
: The present study was carried out by collecting blood from cattle at the slaughtering point during bleeding. This was done with the consent of the owners of the respective cattle at the local municipal abattoir in Ibadan, Nigeria. Therefore as we were not on our own handling the animals, we thought there was no need for ethical approval.