Sexed semen in block calving herds

[Farmer Keith]

What’s people thoughts/experiences on using sexed semen in a block calving scenario?

I dabbled in it after I first did my AI certificate and before I ran a block calving system but didn’t have a lot of joy. Conception rates were sub 30% if I recall correctly. Has anyone used sexed in cows since and had any better results? Ideally they’d need to be at least 50% in my head or the loss of time would have too great of an impact. (70% with conventional last autumn).

I’d only use it for the first 3 weeks on select cows but it would be annoying to see a huge chunk of what would be my best cows lose 3 weeks, especially when the Arla seasonality scheme makes Autumn calving difficult unless your block is super tight anyways, but that’s a different topic entirely!

 

[dairyrow]

according to CIS my conception rate was 25% for most of the bulls. I don't think i've been alone in having not to good rates this year tbh.

 

[In the pit]

Lic did a big experiment on it in nz ,12000 cows served conception rate on sexes was 15% lower than conventional semen
We used 50 straws and put them on 2/3/4 calvers that bulled in the first week,,but not sure on results yet

 

[Grazer]

I've tried it in the first week, so that those cows would get another chance of dairy semen in week 3, before the beef bulls go out. Not very impressed. Would have got more replacements using conventional. I was advised years ago that it would be 10% less than your normal rate, but I've found it 10 to 15%. By that I mean, if normally 45%, then sexed would be low 30s. So your 70% would drop to high 50s.

 

[sidjon]

We used it last year, 50 straws produced 38 cows in calf (so very little different rest of cows, except only pick healthy cow for sexed straw so had better chance, cows were mixed age too over 11 week block) and they all had heifers too, except the 10 I lost to tb

 

[Spudley]

Last year we had 60%conception to sexed semen, this year it was 21%. ???

 

[Grazer]

Wow.

 

[Headless chicken]

Last year we had 60%conception to sexed semen, this year it was 21%. ???

Any idea why? Mine was sh!t too. So much so I’m wondering if I’m better off not using it this year and just use more dairy semen all through.

 

[vantage]

Any idea why? Mine was sh!t too. So much so I’m wondering if I’m better off not using it this year and just use more dairy semen all through.

We used it on sync heifers, 50 in total, probably 10 in calf. Being pushed by Arla on bull calves is the problem, plus TB taking IC cows means it’s not much fun atm.

 

[Rossymons]

Any idea why? Mine was sh!t too. So much so I’m wondering if I’m better off not using it this year and just use more dairy semen all through.

Last year we had 60%conception to sexed semen, this year it was 21%. ???

Were both lots from the same company as you bought the previous year?

 

[som farmer]

something we all have to look at, where arla goes, others will follow. Sexed semen on it's own, will not sort the calf job out. But we have a mainly spring calving herd, and we have thought of using sexed on those cows that are not quite in the block, ie dec/jan, and then if conception rates are down, we won't lose time, the other way is to start serving select cows with sexed a week/10 days earlier.
Hopefully, sexed semen will keep improving until conception rates are better, or, as someone posted on here, the use of embryo's, this will give us decent beef calves, irrelevant to the breed of cow. In theory these could replace suckler cows, and therefore reduce our carbon footprint !!!!!! The more I think on this, the better it seems. Let's hope technique improves, and costs come down, as this could solve a huge problem for the beef side. The only other suggestion I have seen, is the use of drugs, to keep cows milking for, say, 2 years, but I can only imagine the public response to that !!!!!!!!!

 

[Headless chicken]

We used it on sync heifers, 50 in total, probably 10 in calf. Being pushed by Arla on bull calves is the problem, plus TB taking IC cows means it’s not much fun atm.

I’ve had our breeding advisor out the other week because we use a lot of minority breeds there’s only one who covers the country. He had a lot of trial data showing success rates at 57% but can’t find the email now. Bull calves are no problem for me. Biggest issue is my expansion and requirement for a fair number of replacements.

Were both lots from the same company as you bought the previous year?

It was my first year doing it and our first year with our own heifers to serve. Ours were walk and chalked after considering sync to not be worth it. I know we made some mistakes but things will change again this year but when you’ve got products like sperm vital that just works. I’m bloody tempted to sync them all serve them All to SV and then chuck 4 bulls in.

 

[som farmer]

I’ve had our breeding advisor out the other week because we use a lot of minority breeds there’s only one who covers the country. He had a lot of trial data showing success rates at 57% but can’t find the email now. Bull calves are no problem for me. Biggest issue is my expansion and requirement for a fair number of replacements.

It was my first year doing it and our first year with our own heifers to serve. Ours were walk and chalked after considering sync to not be worth it. I know we made some mistakes but things will change again this year but when you’ve got products like sperm vital that just works. I’m bloody tempted to sync them all serve them All to SV and then chuck 4 bulls in.

not a bad idea, they don't all calve on 1 day, and you get yourself fully geared up for calving, and you totally 'tune in' to deal with cows calving, we synced 70 hfrs 2 years ago, 67 % held, but calving was 14 days, we didn't do it last year, just jabbed them with oestrogen, as that number of hfrs calving was a bugger in the parlour, either knocking the clusters off, not walking out, or walking back in, and stopping the next lot going out !

 

[farmer on a bike]

We are using sexed semen in our block calved herds. When we sync heifers with Cidrs we put on scratch stickers and serve to the stickers over 2 days and then put the bulls in. Sexed semen has not really changed the conception rate on that have done it on two groups now using 4m/straw sexed semen. We have learnt some bulls are better than others so we use 2 on heifers and 5 overall. On the miklking cows we found poorer conception with first calved heifers and also saw sexed semen conception disproportionately drop when we had a winter dysentery outbreak. Basically it seems conception rates drop disproportionately when cows are stressed in some way.

At the other end, calving mostly heifer calves really improves the enjoyment of calving. We choose to use the sexed semen quickly in the first 10 to 15 days, it probably has pulled conception rate down by around 10-12% (my figures don’t really show that due to conception issues with a beef bull), but starting 2 days earlier seems to help correct the effect on the block.

Doing the theoretical figures then if you have 300 hundred cows, serve 160 sexed you end up with around 20 extra repeats to first service. 13 get in calf on repeat leaving 7 added to the post 6week calvings, so your 6 week in calf rate drops by 2.3%. At least that is my maths. Potentially you have extra beef cross calves to help make up A bit of cost even at today’s prices.

 

[som farmer]

on conception rates, as I have to spend time indoors, I have been looking at fat and protien %'s, on our cows, it seems directly related to conception, as soon as a cow becomes pd+, I have seen them keep a higher constituent %, certainly those cows that are 'problem' cows, do not pick up their constituents, whether this is just co-incidence, or not, on the last pd session of 70 cows, I was 80% correct. I know the link between general nutrition, and fertility, and whether this is just following on from that, I don't know, but I have to do something to stop me going bonkers !!!!

 

[Spudley]

We used 4 bulls from 3 companies (g, a, and c). The bull we used last year was the worst this year.
It was a combination of factors I believe but the most significant was that we used heat detection collars rather than chalk and observation and really struggled to get the timing right. Also we really missed that hour spent in the field with the cows and in hindsight they were probably short of grass at the time. But because we werent going out we didn't know. The collars came off after 4 weeks and things started to improve then.
We will use sexed again next year for the first 2 weeks, but will go back to chalking and observing and I am going to be a lot more on top of the grass.

 

[Spudley]

Also we used a different IBR vaccine pre service and I don't think it worked as well as the original one we were on.

 

[Rossymons]

I'm at a loss why rates have dropped so. It's only semen after all.

 

[Princess Pooper]

not a bad idea, they don't all calve on 1 day, and you get yourself fully geared up for calving, and you totally 'tune in' to deal with cows calving, we synced 70 hfrs 2 years ago, 67 % held, but calving was 14 days, we didn't do it last year, just jabbed them with oestrogen, as that number of hfrs calving was a bugger in the parlour, either knocking the clusters off, not walking out, or walking back in, and stopping the next lot going out !

I think the routine use of fertility drugs by some herds is going to take the next big hit from supermarkets/processors. It does not look good, even when it is being used to sync rather than for reasons of infertility.

 

[In the pit]

not a bad idea, they don't all calve on 1 day, and you get yourself fully geared up for calving, and you totally 'tune in' to deal with cows calving, we synced 70 hfrs 2 years ago, 67 % held, but calving was 14 days, we didn't do it last year, just jabbed them with oestrogen, as that number of hfrs calving was a bugger in the parlour, either knocking the clusters off, not walking out, or walking back in, and stopping the next lot going out !

On a block calving herd you want every animal you've got to calve on day one
You should be ready to go before the first calf hits the ground
Best block calvers are calving half there herd in first ten days