Targetting BCS 5.0 at calving

It is a well known industry target that cows should be a minimum of 4.5 at dry off at the end of May - preferably 4.7, so the cows only have to gain 0.5 of a BCS over winter, to reach the desired target of 5.0 to 5.5 condition score at the point of calving. Cows at BCS of 3.5 should be dried off now. Cows less than 3.5 are unlikely to get to BCS 5.0 by calving even if maximally fed. Remember some supplementary feeds are better at partitioning to BCS than other - maize, barley (cereals) and as we see on a lot of farms now, fodderbeet.

Ideally cow wintering groups would be made up according to calving date  - however if your herd BCS is wide, as is commonly the case, it is suggested to winter the bottom portion of the herd separately and feed these preferentially. You may wish to consider making up wintering groups based on a combination of both BCS and calving date. Our practice can offer a service where we can individually BCS cows and match these with their predicted calving dates. Cows are then split into early calving skinnies, early calving fats, late calving fats etc. Sheds fitted with Protrak makes drafting simple! Also with the current wet weather, the number of lame cows on some farms is increasing, so decisions on dry off and BCS may be brought forward to allow for developing lameness issues.

Phantom Cow Syndrome

Last year our practice conducted a large scale study looking at the incidence of phantom cows and the economics of treating them. A phantom cow is a cow which has had one insemination and does not return within 35 days post insemination but is found to be not pregnant by ultrasound scan. 

In our study 4200 non-returning cows from 14 farms were scanned. On average 10% of non returning cows were found to be not pregnant. (14% in previously CIDR treated cows and 8% in naturally cycling cows).

The risk of a high incidence of phantom cow syndrome increases with a herd history of large condition loss post-calving, metritis, high non-cycler rate, high blood NEFA levels post calving, low BCS at mating, metritis and BVD. In our study half the cows diagnosed as phantoms were treated with a CIDR and the other half were left. We wanted to see if early identification and treatment would lift the 9,10 and 13 week in-calf rate.

On average CIDR treated phantom cows had an increased 9 week in-calf rate of 20%, but the biggest response came from the treatment of phantom cows of BCS 4.0 or less. Treatment of these increased 9 week incalf rates from 25% to 60% in these thin cows (half the cows in the study were 4.0 or less). The economic return for intervention on one farm in the study (900 cows) was $21,000.

Last year our practice conducted a large scale study looking at the incidence of phantom cows and the economics of treating them.

A phantom cow is a cow which has had one insemination and does not return within 35 days post insemination but is found to be not pregnant by ultrasound scan.

In our study 4200 non-returning cows from 14 farms were scanned. On average 10% of non-returning cows were found to be not pregnant. (14% in previously CIDR treated cows and 8% in naturally cycling cows). The risk of a high incidence of phantom cow syndrome increases with a herd history of large condition loss post-calving, metritis, high non-cycler rate, high blood NEFA levels post calving, low BCS at mating, metritis and BVD.

In our study half the cows diagnosed as phantoms were treated with a CIDR and the other half were left. We wanted to see if early identification and treatment would lift the 9,10 and 13 week in-calf rate. On average CIDR treated phantom cows had an increased 9 week in-calf rate of  20%, but the biggest response came from the treatment of phantom cows of  BCS 4.0 or less. Treatment of these increased 9 week incalf rates from 25% to  60% in these thin cows (half the cows in the study were 4.0 or less). The economic return for intervention on one farm in the study (900 cows) was $21,000.