By David Wilson, Donegal (HND 3), Stewart Gallick, Magherafelt (HND 3) and Robert Whitaker, Lisburn (HND 1)

CREAM, a student led project, based at Greenmount Campus (CAFRE), provides Higher National Diploma in Agriculture (HND) and Agricultural Technology Degree (BSc) students with the opportunity to manage a high genetic merit Holstein herd. CREAM provides a unique opportunity for students wishing to study agriculture and is the only project of its kind within the UK and Europe. The herd is milked three times a day, with students carrying out a wide range of tasks including milking, feeding and management decisions such as breeding.

As the CREAM herd comprises 30 high genetic merit cows, yielding an average of 45 litres per day, mastitis can be a problem; this can have negative effects on both yield and composition. To complement the students’ good husbandry and hygiene practices, they recently organised milk screening for those cows that exhibited consistently high somatic cell counts (SCC) and arranged for the Campus vet to demonstrate teat end scoring to the CREAM students.

Screening the milk of persistently high somatic cell count cows allows identification of exactly which bacteria are present in each individual quarter. The milk sample must be removed aseptically in order to minimise false results due to contamination. This must be preceded by the cleaning of the individual teats with an alcohol wipe and the removal of the foremilk. The subsequent microbiological analysis, can identify specific bacteria which will help the farmer use the most effective form of treatment to combat individual cases of mastitis. This in turn will help stop the infection at an early stage therefore reducing the amount of rejected milk. Milk screening of the CREAM herd identified two cows with a higher than average SCC which had the potential to incur penalties for the herd. This allowed the students to implement an action plan to treat these cows as effectively as possible. The students now routinely sample all cows with symptoms of mastitis prior to treatment.

Brian McCauley, Campus vet, instructs Ian Boyce (HND 3 Ag.) on teat scoring.

Teat scoring has the potential to be extremely beneficial to farmers and herd health as it can give information regarding the efficiency of the milking machine. If the milking machine is faulty or has incorrect settings (for example pulsation rates) it may lead to damage of the teat end by causing a build up of keratin in the teat orifice. This can affect milking speeds and lead to the teat orifice remaining open for a prolonged period after milking and therefore leave the cow susceptible to mastitis.

The teat scoring system is based on the appearance of the teat orifice on a 0 to 4 scale depending on the extent of damage:

0 – Perfect teat end. There may be a slight thickened ring although there is no damage to the teat end.

1 – The orifice is slightly to open. It also has lost its normal appearance

2 – A rough area of keratin is obvious, protruding 1-2ml from the raised teat orifice.

3 – Orifice is very rough with keratin all the way round the teat sphincter.

4 – Advanced protrusion 2-4ml long with sphincter giving the appearance of having turned almost inside out.

Only scores of 3 and 4 are likely to lead to an increased level of mastitis. The CREAM herd was found to have an average teat score of 1.35, which indicates that the cows are being milked effectively.

Conclusion

From now on the CREAM students plan to implement teat scoring and milk screening into their action plan for minimising mastitis in the herd, and as such reduce its incidence in the herd.