Is your somatic cell count disimproving? When breeding is in full flow and there is lots of work in the fields, somatic cell count control regularly gets put on the back burner. Often proper controls are not implemented and little or no investigation is carried out.

What are the top areas that need investigating?

1 Keeping problem cows for expansion that should be culled

This is the single biggest threat to good herds in expansion phase. Chronic infected cows are a disaster in any herd but especially in good herds. If there is a very low somatic cell count (SCC) through the main body of the herd then cows can pick up infection very readily from infected high-SCC cows. Your best milking low SCC cows are the most prone, such as heifers.

2 Underestimating the infected cow and poor infection control

Out of date teat dip is common where bulk buying of product is carried out. For many diluted teat products the shelf life is two to three days on dilution. In many cases, these can be diluted for a month’s use.

Some farmers dip clusters in buckets of dilute peracetic acid. This can help to stop spread of contagious mastitis through the liners. All too often, these buckets are overused (eg 20 cows) and cause more trouble than good. The rate is 30ml to nine litres of water and this solution should be discarded after 10 dips.

If problem cows cannot be milked last, this is an alternative. A common cause is underestimating the impact a clinically infected cow can have on a low-SCC herd. Always disinfect the cluster after a problem cow or milk her last. Remember a cow with clinical mastitis was probably shedding for the two previous milkings, and she could have infected other cows during milking.

3 Management of cubicles during grazing season

Teat ends of cows remain open for 30 minutes post-milking. In many yards, cows have access to cubicles post-milking before turnout to grass. They should be restricted from lying on cubicles post-milking as this is a common cause of environmental mastitis during the summer months.

4 Expansion without adequate housing facilities

This is a significant problem as we hit expansion phase. Significant dairy units are overstocked (eg 120 cows in 100 cubicles) resulting in a significant environmental mastitis challenge and inducing a significant stress problem in cows. A plan needs to be put in place when weather conditions do not allow turnout.

5 New labour into farming enterprise

This is getting more common as scale increases. Cows are creatures of habit and when new labour enters a farm it is crucial to communicate what is required. Milking routine accounts for over one-third of the cases of high SCC. Technique should be consistent and robust.

6 Inadequate dry cow regime

A number of these cases arise every year, and have a dramatic effect on the herd until the next dry period, so you can see how this can be a very costly mistake. Main causes are prolonged use of same dry cow antibiotic and a resistance issue may be present.

This can be picked up by analysing your cell check AHI report in your milk recording. In this sheet, it evaluates the cure rate over the dry period and establishes new infection rate over the dry period. All too often, poor dry cow technique is responsible; this can cause mastitis well into the first 60 days of the subsequent lactation.

7 Milking parlour maintenance and changing liners

Poor maintenance is an ongoing issue. The liner is the only part of the parlour to come in contact with the cow. New liners will ensure less bacteria and better milk out, especially in heifers. You must change liners every six months or after 2,000 milkings. Vacuum settings and pulsation should constantly be monitored.

8 First milk recording too late

This is a significant issue in spring-calving herds, as many farmers wait until all the cows have calved and bred again. At that stage, a significant problem can have developed. With a compact calving regime (ie > 70% in six weeks) the first milk recording should be scheduled for end of February/start of March.

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