Big variation in conception rates to AI bulls

Matt23

Member
Livestock Farmer
Hi, I’m new to AI’ing and I’ve been using different Holstein sires from various AI companies over the past year and a half and I’m seeing big variations in conception rates to different bulls and was wondering is this common?
For example I’ve used 30 conventional straws from one bull with over 20 confirmed pregnancies and yet there’s another bull that I’ve used 30 conventional straws from with only 10 confirmed pregnancies.
Is this common or is it just bad luck for the latter of the two bulls?
I also seem to get higher conception rates with certain sexed bulls than I do with other conventional bulls straws
Thanks in advance for any replies!
 

frederick

Member
Location
south west
Hi, I’m new to AI’ing and I’ve been using different Holstein sires from various AI companies over the past year and a half and I’m seeing big variations in conception rates to different bulls and was wondering is this common?
For example I’ve used 30 conventional straws from one bull with over 20 confirmed pregnancies and yet there’s another bull that I’ve used 30 conventional straws from with only 10 confirmed pregnancies.
Is this common or is it just bad luck for the latter of the two bulls?
I also seem to get higher conception rates with certain sexed bulls than I do with other conventional bulls straws
Thanks in advance for any replies!
You also have to be careful that your bull matching hasn't created this.
I've had sexed semen conception in hight to mid 60s bit at the same time triple blue at 54.
However I chose the most fertile cows for sexed usage.
 

Borney92

Member
Hi, I’m new to AI’ing and I’ve been using different Holstein sires from various AI companies over the past year and a half and I’m seeing big variations in conception rates to different bulls and was wondering is this common?
For example I’ve used 30 conventional straws from one bull with over 20 confirmed pregnancies and yet there’s another bull that I’ve used 30 conventional straws from with only 10 confirmed pregnancies.
Is this common or is it just bad luck for the latter of the two bulls?
I also seem to get higher conception rates with certain sexed bulls than I do with other conventional bulls straws
Thanks in advance for any replies!
Hi Matthew

Generally bulls all differ in their conception rates but all have passed the quality test.
In the trial done by teagasc on sexed semen, it was found that some bulls sex better than others and same goes for conception rate.

As for why one batch of straw held better than the others there could be any amount of reasons.

Weather,feed,Dim, calving difficulty ect

Just keep on practicing.
 

Matt23

Member
Livestock Farmer
Thanks for the replies, I know my small sample isn’t large enough to come to any conclusions over so that’s why I wanted to get others opinions. It probably is more to do with the cows fertility than the bulls, I just find it strange that I can get better conception rates with sexed than certain conventional semen
 

jerseycowsman

Member
Livestock Farmer
Location
cornwall
Thanks for the replies, I know my small sample isn’t large enough to come to any conclusions over so that’s why I wanted to get others opinions. It probably is more to do with the cows fertility than the bulls, I just find it strange that I can get better conception rates with sexed than certain conventional semen
We find variations, some bull semen is definitely more fertile than others
 

SFI - What % were you taking out of production?

  • 0 %

    Votes: 80 42.3%
  • Up to 25%

    Votes: 66 34.9%
  • 25-50%

    Votes: 30 15.9%
  • 50-75%

    Votes: 3 1.6%
  • 75-100%

    Votes: 3 1.6%
  • 100% I’ve had enough of farming!

    Votes: 7 3.7%

Red Tractor drops launch of green farming scheme amid anger from farmers

  • 1,292
  • 1
As reported in Independent


quote: “Red Tractor has confirmed it is dropping plans to launch its green farming assurance standard in April“

read the TFF thread here: https://thefarmingforum.co.uk/index.php?threads/gfc-was-to-go-ahead-now-not-going-ahead.405234/
Top