The Travelling Vet

14

PIG

‘In each human heart are a tiger, a pig, an ass and a nightingale. Diversity of character is due to their unequal activity.’

Ambrose Bierce

Adrian was out of town visiting one of his pig clients in Norfolk. As a pig specialist, he travelled the length and breadth of the country to see clients, but this often meant if a client needed an imminent visit and he wasn’t available then he would request someone more local to attend. One such regular request was to perform a post-mortem examination (or ‘PM’). Pig farms usually have such large numbers of livestock that disease spreading through the herd causing high morbidity or mortality is a constant worry. For this reason most pig units employ very strict biosecurity protocols; showering and changing clothes before entering a facility are not uncommon procedures and visitors to these units are required to have a period of between twenty-four and forty-eight hours without any contact with pigs before entering.

So if there is a sudden, unexplained death of a pig, a farmer is usually keen to find out the cause so that they can respond appropriately. If an infectious disease is responsible, then shutting down the farm, quarantining a group, and treating or vaccinating them will help prevent the disease spreading. The sooner the farmer can implement such policies the better the outcome will be.

In herd, flock or group animal management, a post-mortem is a vital part of the armoury, key to determining why an animal has died and giving information about a wider problem in a population of animals, for example a heavy worm burden, nutritional deficiencies or an infection.

‘Jon, it’s Adrian,’ came the voice down the phone. ‘You wouldn’t happen to have some time this morning to do a post-mortem for me, would you? Jane said you might be free late morning.’

‘I’m just on my way to Blackman’s now to see a downer cow, but then I’m free till the afternoon.’

‘Great. I’m up in Norfolk just now, but Graham Bartlett has a post-farrowing sow that he found dead this morning and wants her checked out. It doesn’t sound like anything too suspicious, but I said I’d get someone to pop along and check her out. Is that all right?’

‘Yeah, sure. Remind me where Graham’s farm is?’

‘Jane will give you directions. It’s a big unit, but Graham said he’ll bring the sow to the outside of the buildings so that you don’t have to shower in. You go down the long driveway towards the buildings, you’ll see some large feed hoppers on your left-hand side and the sow will be by them. If you give him a call when you’re on your way, then he’ll meet you there. I’d take the usual samples – lung, liver, kidney, spleen, heart, jejunum, ileum, colon, caecal fluid and mesenteric lymph nodes should cover it – and send them off to IDEXX …’

IDEXX is a prominent multinational company whose laboratories specialize in veterinary diagnostics.

‘Oh,’ he added, ‘you haven’t been near any pigs for two days, have you?’

‘No, don’t worry, the last pig I saw was a couple of weeks ago.’

‘OK, great. Just had to check. Thanks, Jon.’

I must confess, the call didn’t thrill me. Post-mortems are never fun, though of course they’re an essential part of the job, but naturally I much preferred dealing with live animals rather than dead ones. Occasionally you would find some really interesting pathology, but often it was a lot of fumbling around inside a cold, odorous carcass examining organs and taking samples, with no obvious visual pathology, and hoping the lab might shed light on the cause of death. On top of this, it was a client I hadn’t been to before. Adrian was obviously their preferred vet, so Graham would be disappointed not to see him. I was sure he’d be understanding and accepting, but Adrian would be the benchmark against which I would be compared.

I temporarily put the call out of my mind and headed to Mr Blackman’s cow. It was a fairly uneventful visit. The cow had milk fever, a condition that mainly happens around calving time in old dairy cows, although any cow can be affected. A huge increase in milk production around this time drains calcium from the blood and the cows are unable to replace it quickly enough. The cow therefore has much less calcium for her own bodily requirements such as muscle contractions. In its mild form the cow is simply unable to stand, but if left untreated it can be fatal. Fortunately, this cow was on the milder end and after I slowly injected 400 ml of calcium borogluconate into her vein, she was up and walking around as normal. It’s always very satisfying when a simple treatment gives such a dramatic response that you feel like a miracle worker. So with my mood bolstered by that visit I rang Jane to let her know I’d finished the call, received her directions to Mr Bartlett’s farm, and set off.

The sat nav reckoned it was twenty minutes away. As I drove, I mentally rehearsed the samples I would be taking and went through a checklist to ensure that I had everything I might need. Large scalpel blades, plenty of pots and a pair of arm-length gloves should cover it, and these were all knocking around somewhere in my car, the only immediate problem being tracking them down.

The farm was down a long straight, concreted driveway that ran between two large open ploughed fields. As I approached the entrance into the farmyard a large sign greeted me:

STOP! THIS IS A BIOSECURE AREA.

NO UNAUTHORIZED ENTRY.

ALL VISITORS MUST REPORT TO RECEPTION.

The reception was off to the right, tacked onto the first in a row of large, green, corrugated aluminium-sheeted buildings, obviously where the pigs were housed. Each building had a large 40-foot-tall feed hopper at the end of it, from which a pipe fed into the building. Off to the left of the farm entrance were three concrete silage ‘clamps’, the first of which was the general rubbish dump, and the next two apparently used as the unit car park. In front of the first clamp stood a yellow Matbro telehandler, a sort of forklift tractor, with a grain bucket attached. As I drove into the farm looking for somewhere to park, I caught sight of four pig’s trotters sticking out of the grain bucket. So this was obviously the sow I had to post-mortem. I pulled up alongside.

As I put on my wellingtons and waterproofs by the boot of my car, a broad-set man in his mid-forties, in the classic farmer’s garb of green wellingtons, blue jeans, checked shirt and green gilet, came towards me.

‘Jon, I presume? I’m Graham.’

We shook hands.

‘Nice to meet you.’

‘Thanks for coming. Adrian doesn’t think it’s too much to worry about, but I’d rather be safe than sorry.’

‘Sure, I completely understand. I presume this is her,’ I said pointing to the grain bucket.

‘Yeah. You all right to do it in there? I just thought it would be less mess and easier to clean up.’

‘Yup, no problem.’ Having grabbed the various items I needed, we walked over to the front of the Matbro. The deceased was a full-grown Large White–Landrace cross-breed that must have weighted about 250 kg. Her twelve udders were all engorged with milk, indicating that she had been feeding piglets, which made her sudden death all the sadder. Having put on my arm-length gloves, followed by a pair of latex gloves, I started examining the carcass. On first inspection there were no obvious clues; no discharges from her mouth or nose, no diarrhoea; she had some blood around her back end, but she was otherwise in good bodily condition.

‘When did she farrow and was she fine yesterday?’ I asked.

‘Farrowed two days ago, her third litter, and yeah, she seemed to be feeding all twelve piglets no problem. No clues of illness or any suggestion we’d find her in this state this morning.’

‘There certainly isn’t anything obvious externally. Let’s open her up and have more of a look.’ I picked up my large scalpel and started cutting from the umbilicus, forward to the sternum and backwards to the pubis. As I cut through skin, muscle, and then into the abdominal cavity, gas-filled intestines started spilling out. Pushing them out of the way I orientated myself. The liver was an easy place to start. It looked fairly normal, and so did the spleen, so I pushed the intestines to one side and located the stomach, then dug deeper and found the kidneys. Everything looked normal.

‘Don’t you make a bigger incision than that?’ Graham commented, leaning over my shoulder. ‘Adrian cuts from the chin to the butt and just opens them right up.’

He had a point. I was used to doing PMs on lambs, where the focus was generally the abdominal cavity, looking for a worm burden or clostridial disease. You could cut through the diaphragm and check out the lungs for signs of pneumonia, but if it required anything more thorough than that, I would normally advise the farmer to take the carcass to the local veterinary laboratory where they could perform a complete PM. But Graham was right: I should open her up fully, especially if that’s what Adrian did. The only problem was that I didn’t have the right equipment to cut through the ribs.

‘I’ll open the thorax in a bit. You, er … you wouldn’t have a saw I could use, though, would you? I’m afraid I don’t have one with me.’

Graham gave an audible snort of indignation. ‘There might be one in the back of the Land Rover,’ he said, returning moments later with a rusty hacksaw. ‘This do?’

‘Perfect, thanks,’ I said, taking it from him rather gingerly. I was now feeling a little flustered, so I broke away from my inspection of the jejunum and started sawing through the sternum to open up the thorax and examine the heart and lungs. In such a big sow it was fairly hard physical work, but after a few minutes I was cracking open the completely normal-looking chest. The lungs and heart all looked very healthy, with no evidence of pneumonia, no pleural effusion, so I felt for the mediastinal lymph nodes, which were also normal. I moved back down the abdomen, ready to finish my visual inspection and then start cutting into the organs to take samples. I reached the back of the abdomen and as I fumbled below the intestines I pulled up a section of colon. It was thickened and very engorged, inflamed and bloody.

‘Hmm, this doesn’t look too healthy,’ I commented, turning to Graham.

‘What is that?’

‘Colon. Looks quite haemorrhagic.’

‘What are you thinking?’

‘Well … haemorrhagic colitis can be caused by swine dysentery.’

‘Seriously? Isn’t she a bit old for that? She hasn’t had diarrhoea.’

‘It is usually a disease of piglets, but it can occasionally affect sows. But I agree, it doesn’t make much sense. Maybe she developed a severe septicaemia and with her immune system being suppressed post farrowing it really hit her?’

‘Well, if it’s swine dysentery, this could be trouble. Can you take some samples and get them sent off today? We need to get on top of this ASAP.’

‘Sure. It’ll go off to IDEXX today and I’ll put an urgent request on it.’

I then set about cutting out a section of colon, putting it into one of my formalin pots, repeating the process with the jejunum and ileum before moving on to take samples from the liver, kidneys, spleen and lung. I then removed the heart and opened it. There was no evidence of muscle enlargement, but I took a sample from that, too. Everything seemed completely normal except for the colon.

With all my samples taken, I turned to Graham. ‘Do you need me to stitch her up?’

‘No, don’t worry about that. Just get those samples sorted and sent off.’

I removed my gloves and then labelled the pots before gathering everything together and washing myself off at a tap next to the reception building.

Cleaned down and with everything loaded up, I climbed into the car to head off.

‘I’ll call Adrian and let him know what I’ve found. One of us will be in touch in the next day or two, but in the meantime I’d isolate any other sows that were in the same group as her.’

He thanked me, and I drove out of the farm, back down the long driveway. The sooner I called Adrian the better, I thought.

‘Let me guess,’ he said. ‘You didn’t find anything?’

‘Well, actually, I did. I mean, most of it was completely unremarkable, but the colon was severely haemorrhagic and inflamed.’

‘Seriously? That’s not good. Had she been scouring?’

‘No, literally nothing. I mean, there was a bit of blood around her back-end, and she farrowed two days ago, but otherwise everything else was normal.’

‘Hmm … Odd for it to be swine dysentery. Did he say how the piglets were doing?’

‘Yeah, the piglets are all fine.’

‘Interesting. Well, I assume you took some samples, so get those sent off as urgent and I’ll give Graham a call and have a chat with him.’

‘Will do.’

‘Thanks, Jon. It seems it was just as well we did that post-mortem.’

I drove back to the practice, checked with Jane that there weren’t any pressing calls and set about filling in the lab submission form and sealing up the pots, which I left in the out -tray for the duty nurse to package up and send off to IDEXX.

Adrian telephoned two days later. ‘Have you seen the IDEXX results on Graham’s sow? They’re back.’ There was a tone in his voice that I couldn’t quite decipher.

‘No, I haven’t. What did they say? Is it good news?’

‘Um, well, I’ll email it over to you. I think you should have a look. Why don’t you give me a call back when you’ve read it?’

He hung up. What was that all about? He seemed in a very good mood, almost as if he’d been trying not to laugh.

Moments later my phone pinged with an incoming email. It was the test results from Adrian. I opened the attachment.

‘IDEXX Laboratories Test Report,’ I read. ‘Owner: Bartlett. Patient: sow. Age: adult. Partial report. Samples submitted: lung, heart, liver, spleen, kidneys, jejunum, ileum, colon. History: sudden death of a two-day post-farrowing sow. Histopathology …’ I skimmed through the usual preamble, and then moved down. ‘Diagnosis: This was an unusual and somewhat confusing submission. Eight sample pots were submitted, all clearly labelled to identify them. Our attention was drawn to the sample labelled “Colon” and the concern raised on the submission form that this was inflamed, haemorrhagic tissue suggestive of swine dysentery. You can imagine our confusion, then, when on histological examination we confirmed that the colon sample submitted was in fact normal, healthy uterus, consistent with two days post farrowing.’

I put my hands to my head in sheer disbelief. The section of tissue I had found, and then confidently shown to the farmer as a piece of severely inflamed, bloody gut was not gut at all, it was the uterus; and furthermore it was exactly as the uterus should look two days after producing a litter of twelve piglets.

‘The rest of the results are pending,’ the report went on, ‘but if you would like to discuss this case further, then please don’t hesitate to call to speak to one of our pathologists.’ Somehow I didn’t think that was a phone call I would be making any time soon. I imagined the pathologist had had a great laugh constructing that report over their tea break. I wonder if they had a wall in their staff room for their funniest submissions. If so, this one would have been pinned in the middle. How utterly, humilatingly embarrassing! After five years of vet school, and I couldn’t distinguish between a sow’s intestinal tract and her uterus. So that explained Adrian’s tone of voice on the phone. Well, at least he’d seemed amused rather than angry – though that also meant there was no way he’d be keeping this one quiet. I rang him back.

‘So … not swine dysentery then,’ he said, laughing. ‘That’s good.’

‘I’m really sorry, Adrian. I can’t believe I did that.’

‘I love the line “You can imagine our confusion …”. That’s pure brilliance, Jon! It’s the best lab report I’ve ever seen … I think we should get it framed and hang it up in the office. It’s really made my day.’

‘So … do you want me to ring Graham Bartlett and let him know?’ I said eventually.

‘Don’t worry, Jon,’ he replied, more serious for a moment, immediately understanding my position. ‘I’ll call him. I might omit the fact that you sampled the uterus instead of the colon, though. I’ll just tell him it’s nothing to worry about and that you were a tiny bit enthusiastic with your diagnosis. He’ll be so relieved to know it’s not swine dysentery he probably won’t ask too many more questions.’

‘That’s good of you, Adrian, thank you,’ I said, the relief flooding through me. ‘And once again, I’m so sorry …’

‘Honestly, there’s no harm done, and you’ve given us all something to laugh about. These things happen … Not that, to the best of my recollection, I’ve ever confused the reproductive tract for gut, but we all make mistakes, so don’t stress it. It’ll be a good story for the Christmas party.’

I groaned. The practice’s Christmas party was only a few weeks away, and with the staff from all the different branches attending, with wives, husbands and partners in tow, there’d be over a hundred guests. Hopefully he’d have forgotten all about it by then.

In fact, he didn’t, and at the end of the Christmas meal, and after a few awards had been handed out to various people, Adrian took enormous pleasure in reading out loud the full IDEXX pathology report to the assembled throng, before presenting me with a step-by-step guide entitled ‘Five Easy Ways to Distinguish between the Gastrointestinal Tract and the Reproductive Tract’.

Pigs: fast facts

Sus domesticus: The domestic pig

Distribution: Considered a sub-species of the wild boar which is originally native to much of Eurasia, North Africa and the Greater Sunda Islands, it is now distributed more globally.

Names: A male is called a ‘boar’, a castrated male a ‘barrow’, an adult female a ‘sow’, a female under a year that has not bred a ‘gilt’, and the young a ‘piglet’. A group of pigs is called a ‘sounder’.

Life span: About 15–20 years.

Habitat: The wild boar’s natural habitat is a deciduous forest, but the domestic pig tends to either live in concrete sties or muddy paddocks.

Diet: Pigs are omnivores, which means they consume both plants and animals. In the wild they are foragers, eating leaves, roots, fruits, flowers, insects and fish. As livestock they are fed predominantly on corn and soybean meal.

Gestation: 116 days, giving birth to up to 15 piglets.

Weight: About 1.3 kg at birth, reaching 140–300 kg as adults.

Growth: A piglet would naturally wean at about 8 weeks as the sow’s milk production declines. Commercially, a piglet will be weaned at about 3 weeks when it reaches a weight of around 6.5 kg. They reach sexual maturity between 3 and 12 months, but are not fully grown till 2–3 years of age. A gilt will be bred at about 6 months, and a boar used from 8 months. Pigs will be slaughtered for meat anywhere between 4 and 12 months.

Body temperature: 38.6–39.2 °C.

Interesting facts: Pigs have very few sweat glands and thus regulate their body temperature by wallowing in mud and using it as a sunscreen. Their most developed sense is that of smell, which is why they have been trained to locate truffles underground.

Conservation: It is estimated that there about 2 billion pigs in the world, over half of them in China. There are 17 different species within the genus Sus and several hundred different breeds of domestic pig. One of the biggest welfare concerns surrounding pigs is the use of farrowing crates that are designed to prevent a sow accidentally squashing her piglets. A metal cage on a bare concrete floor, these crates are often so narrow that a sow struggles to stand up and lie down and is unable to turn around. In many systems where farrowing crates are used, sows are kept in them for most of their lives, unable to express such normal behaviour as foraging, exercising and socializing. Charities such as World Animal Protection work tirelessly with one simple goal: to create a world where animals are free of suffering. See: www.worldanimalprotection.org.uk.