If every farm could reduce the level of forced culls by 10%, it would save the industry £32m a year.

The latest results from Kingshay Dairy Manager show 68% of cows leave the herd for forced reasons related to health and fertility, while 32% are selected to leave for performance and other management issues (see chart, left).

Culling decisions should be based on keeping the most profitable cows on the farm and control of forced culling is the vital factor, giving you the option to reduce the herd culling rate or sell less profitable animals.

Not being in control of which cows leave the herd is expensive. And with increasing consumer awareness of cow management practices, it’s also vital accurate data is available to allay misconceptions.

leaving-reasonsThe proportion of forced versus selected culls have changed little in recent years. Analysis of historical results from progressive herds using the Kingshay Dairy Manager service (see table at end of article) show despite yield increasing by more than 1,350 litres a cow and herd size by 50 cows, the overall culling rate and proportion of forced and selected culls has remained relatively constant.

Age of culls

lactation-ageIt is generally believed cows need to milk for three lactations before they have covered their full rearing cost. Evaluating a cow’s leaving reasons by lactation age shows 45% of cows leave within their first three lactations, and more than three-quarters of these culls are forced (see graph, right). This level of young culls has fallen from 52% when Kingshay first evaluated culling reasons, but still represents lost potential, slowing down the rate of genetic improvement within the herd.

Effect of herd size and yield

Some would argue that larger, high-yielding herds are bound to have a higher culling rate and a greater proportion of cows forced to leave for health and fertility issues. However, analysis shows this is not the case. It’s not the size or system that matters; it’s the management and level of efficiency that has the biggest effect.

Ask yourself the question: “Why are cows leaving my herd?” A more in-depth evaluation of the leaving reasons highlights the largest issues (see graph below).

individual-leaving-reaons

Health factors represent the largest reason for culling, accounting for 40% of culls, followed by 28% for fertility issues, but many of these are related. For example, lameness can be the underlying cause of a number of other issues, as having sore feet will reduce a cow’s time at the feed barrier, reducing yield, body condition, immunity to mastitis and the likelihood of getting in calf.

Mastitis is the greatest health leaving reason, accounting for 9.1% of cows leaving the herd, and when combined with those leaving for high cell counts, 14.6% of leavers go for mastitis-related issues.

A combination of good cow management records and taking time to stand back and look at what your cows are showing you will highlight areas to focus on.

All herds should have key performance indicators (KPIs) in place that are monitored regularly through herd recording services. These are valuable management tools to help improve herd longevity, working towards the ultimate aim of improved herd welfare and better financial returns.

Trends of cow leacing reasons – year ending March

2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012
Cows in herd 150 160 156  153  162  169  171 186 186 202 207 201
Milk yield (litres a cow) 7,005  7,368  7,530  7,778  7,877  7,992  7,929 7,712 8,008 8,345 8,518 8,350
Leaving rate (%) 23 24  26 24  24  24  22 22 25 25 27 26
% of leavers (forced) 69 68  66 68  71  71  70 70 70 71 69 68
% of leavers (selected) 31 32  34 32  29  29  30 30 30 29 31 32