Chapter 03 - TB

During those few seconds between sleeping and waking, when you are trying to sort out what day it is, it dawned on me that today was the results of a second TB test on Bluebell II. Another fly in the ointment (or dung) of farming is the continuous threat of TB in cattle. 63 days ago our cows were brought in and put through the race for the annual TB test.

The test is made this way. Two injections are made into the skin at the neck with very short needles – a top injection of bird (avian) tuberculin (the liquid is colour-coded red), a lower injection of cattle (bovine) tuberculin (the liquid is straw-coloured). The hair is clipped so that the injection sight is exposed. After clipping but before the injections, the thickness of the skin at both upper and lower sights is measured. These measurements are clearly recorded, together with the full identification of the animal i.e. full ear tag number (yellow and metal), breed, age and sex. We just hope that it is not raining as we do our test outside and when the vet tells me the skin numbers 8/8 or 12/10 I do not have to write them in a soggy book which might make them later illegible.

During the next few days, Roy anxiously looks at their necks to see if there are any bumps. Three days later they are all brought in again and driven through the race (a restraining sort of corral with a gate at the end with a mechanism you can put their heads in to keep them there). This time it is to detect “oedema”, seen as lumps at the injection sight. Measurements of the skin are then compared with those of the first day. If the bottom lump is bigger than the top lumps by a small amount then the animal is inconclusive. If the bottom lump is more than the top by 3 or more it is a TB reactor.

Inconclusive reactors (IRs) have to be retested not sooner than 60 days later and have 2 retest chances. On the second and final retest of an IR, if it is found to be inconclusive again it is taken as a reactor. Reactors have to be sent to slaughter and be PM’d (post-mortemed).

It is agonizing. Will the vet take an extra few silent minutes to check for that bump? Will he nod and say OK, or will he have that solemn look, recheck her ear tag and put a cross by her number in the book? After scrubbing and disinfecting his waterproofs our vet, Mike, came in and had a cup of tea, and told us all the rules as he signed the movement book, which is a record of all animal movements on and off the farm and their medications.

Unfortunately Bluebell II was a doubtful, which means that the farm is put under movement restrictions and we cannot sell cattle through a market or move them to another farm until she has been tested again and hopefully cleared. She should also be isolated from the other cows on the farm – it’s amazing what hedges they can get over to join their mates!!

So what would today bring? Bluebell II had had her second lot of injections and this was result day again. It wasn’t Mike, our usual vet, it was a very nice lady vet from the ministry who arrived, and Bluebell was presented to her in the race. She very carefully examined the injection sight and measured the skin with a pincer-like gadget! We waited for several very long minutes. “Yes, all clear,” she said. Magic words. Bluebell is released from the race and happily goes back to the rest of the herd – all of a sudden life goes back to normal again – until next year!!
Monica Olds