With clusters hitting teats all over the country in spring calving herds one disease we must watch out for is clinical mastitis. There is always a lot of confusion between clinical and sub clinical mastitis.
- Clinical mastitis is mastitis with inflammation, milk clots etc and can vary between local visible mastitis, swollen udders to clinically sick cows. These cases are usually from the introduction of infection from bacteria in the environment.
- Subclinical mastitis is often where milk looks normal but Somatic cell count can be very high. This is often more chronic and is often spread between cows usually in the milking parlour.
I had a classic case of clinical mastitis problems in a herd this week. I got a call from a farmer with a young and expanding dairy herd. A large number of heifers calving in this month. He had 5 cases of clinical mastitis in the last 10 days. Each heifer that was affected had a swelled quarter, heat, pain, milk clots and one got quiet sick. All these cases where in the first week after calving and on questioning there were also two cows in the last 3 days freshly calved that were treated for mastitis.
With about 55 calved this indicated very quickly something was wrong!
Now we could focus on treatments antibiotic tubes, injections but this was only going to be a short term solution. Arguably the treatment regime was quiet good, but still wasn't getting the desired results.
He had taken samples and frozen them, this was on previous advice to help send a number of samples to try and diagnose the bacteria involved(these samples where taken before treatments of clinical cases).
Before I arrived on farm the milking machine technician had been called as the machine was most likely to blame?
Of course the machine can play a role but I wasn’t surprised a report that found no issues.
I also had got some strong personal views of what might be happening. The increase in the number of fresh cases just after calving raised a strong suspicion about where the potential infection was coming from.
So on farm where did we go next?
The machine was ok and milking routine was fine. The answers started coming when we looked through particularly heifers. As we examined udders they scored low on hygiene with some quiet hairy also. Numbers where growing meaning dry cow accommodation in straw beds was quiet crowded. This had lead to conditions being slightly dirty but also feed space had become an issue. We subsequently blood tested heifers for BHB, with several high readings there was some early evidence of nutritional stress. Silage quality was average and supplementation had begun with rolled barley a week out from calving.
So our next discussion was in very simple terms what might be happening. When clinical mastitis is occurring bacteria enter the teat through the canal over come the local defences leading to infection and varying degrees of clinical symptoms in the quarter, udder and cow.
So one of two things or both could be happening. The amount of bacteria could be very high overcoming local defences(immunity). Or the immunity can be affected or lowered leading to bacteria causing infections easier. In this case I actually think both scenarios were occurring.
We must remember early lactation is always a peak risk for mastitis anyway. This is because stress around calving causes immunity to dip and peak lactation creates a huge energy demand from the cow. This means in early lactation we need to be extra vigilant around mastitis control.
This herds problem was beginning though in my opinion before a drop of milk flowed from the cow. They were under nutritional stress and also the environment wasn't quiet what it should be in the weeks leading up to calving.This meant most likely bacteria entering the udders in the two weeks before calving. Then with the combination of immune pressure and infection pressure we were seeing this spike in clinical mastitis cases.
The likely bugs causing this problem can be ecolis and strep uberis in my opinion (we have no cultures yet).
We needed to take action because clinical mastitis like this can be very expensive mainly because of production losses over the lactation. Also with these types of infection cows can often get very sick and can even die from peracute mastitis.
We agreed little could be done with housing space this year but agreed it was a priority long term plan. We needed more straw bedding and cleaning of close up cow groups. Particularly heifers, they were also to be brought through the parlour for 7-10 days precalving once daily to apply teat dip. We also made a makeshift feeding space with wire at the end of the yard to help intakes. We also agreed to increase energy intakes in close up groups feeding meal for 2 weeks before calving. For the next 4 weeks they are also going to predip all cows and hefiers before milking with a special predip (short acting agent not affected by organic matter). We have discussed also singeing udder hair in some!
We are also strongly considering using a new product on the market called Imrestor. Although often slow to talk or advise products on my blogs this is one I find very interesting. It is new technology which when injected (2 shots day 7 before calving and 24hrs after calving) stimulates the cow to produce more neutrophils. These are white blood cells that help fight bacterial infections. It costs about 30 euro per cow for the two injections.
At that price some will ask why the bloody hell would you even consider it? Well we can only alter management so much, still unfortunately leaving cows under pressure so it would be a good insurance policy from data and what I've read about its effectiveness particularly in the heifers. It will increase these white blood cells which help fight these intramammary bacteria.
Working well it will certainly pay back versus production losses due to clinical mastitis. This decision is still being pondered and probably will be decided upon in the morning. The reality being although expensive these type of innovate products give us something to fight back with particularly when we are going to be limited around antibiotic usage in milking cows in the future.
The long term plan on farm is however the most important reducing environmental infection and nutritional stressors in close up cows/heifers this will take time, planning and money.. Clinical mastitis should always be investigated in early lactation with conservative costs of around 250-300 euro per case mostly in lost production!!!