by John Hicks
There were various refinements we used to improve our success rates. Sometimes we injected small but concentrated doses of anaesthetic into the vein to stop the convulsions while the magnesium was run in, and often we diluted the magnesium solution with calcium borogluconate to lessen its impact on the heart. This made sense because hypomagnesaemia and hypocalcaemia often go hand in hand. Sometimes, if the beast was nervy and teetering on the borderline – still standing, but just on the point of going into convulsions – we would run the magnesium slowly under the skin, because just trying to restrain nervy cows in order to insert a needle in the vein was enough to tip them into full-scale threshing-machine mode, whereas if the solution was trickled under the skin with minimum restraint or stress, and the cow was left quietly alone, the magnesium would slowly take effect and calm her down. It was all a matter of clinical judgement based on experience. The emphasis, for the moments of your call-out, was on treatment, and that was where the drama lay; the interest, however, lay in the science.
John Pauli was interested in the magnesium concentrations in the cerebro-spinal fluid (CSF) of these cows. We knew that their blood serum levels were low, but what of the concentrations in the fluid surrounding the brain? How readily did magnesium cross the blood-brain barrier? If magnesium in the blood were slow to cross into the brain fluid perhaps it would explain why treatment responses were so variable.
Unfortunately, it is quite difficult to obtain CSF samples from a cow, even if it is compliant and restrained in a crush. It involves inserting a long, fine needle through the tough skin and ligaments at the back of the neck, advancing it through a gap between the atlas vertebra and the back of the skull, and tapping the fluid from a structure called the cisterna magna. John wanted to obtain samples of CSF from the cows while they were convulsing. He accompanied me on my rounds day and night hoping to see a convulsing cow and get the farmer’s permission to obtain a CSF sample from it. On a few occasions we were there at the right time and, I’ll never know how, he did manage to hit the cisterna magnae of several thrashing cows. As I recollect, for all his efforts, he never obtained sufficient samples for a statistically valid study of the CSF of hypomagnesaemic cows. But he did help me with a larger study of serum magnesium levels.
Some of the call-outs were quite dramatic. Grass staggers was more of a problem in some herds than others. Many of the supposedly “normal” cows in these herds seemed to be particularly touchy. A critical time was when they came in for milking. A farmer would start putting the cups onto a tense and excitable cow. She would lash out with a foot. He would swear at her. The tension in the shed was raised a notch, and she would fall over and start convulsing. Sometimes, in her aimless thrashings, she might drag herself under the bars and tip into the milking pit, totally disrupting the milking session. Tension is transmissible between cows and men, and all hell could break loose as other hypomagnesaemic cows caught the mood. The farmer might end up with a couple of cows upside down flailing their legs in the pit and a couple of others thrashing about on the platform. Pandemonium reigns. Call the vet!
We blood tested the supposedly normal cows on these farms to find out why they were so susceptible to grass staggers. Quite often the results came back within the expected reference range for serum magnesium, a bit on the low side, perhaps, but taken in isolation each cow could be said to be “normal”. However, we noticed that the reference ranges used by the animal health laboratories in New Zealand were considerably lower than those I had been familiar with in Britain. When we found that our samples from several herds were consistently on the low side of “normal” we wondered whether the data used in NZ cows was skewed because New Zealand cows were chronically deficient in magnesium, and if so why? John, Hank and I also had a hunch that hypomagnesaemia was more prevalent in herds using high levels of potash fertilizer. It was known that potassium competes with magnesium for uptake by pasture, so these animals were probably grazing grass low in magnesium. This was difficult to prove directly because the magnesium levels in pasture fluctuate rapidly from day to day. As I went round the herds taking blood samples, it also became apparent that chronic hypomagnesaemia was tied in with other conditions such as “Taranaki anaemia” and an udder affliction the local farmers called “leatherbag” (also “caked udder” or “rubber bag”). To my regret when we published an article about this in the New Zealand Veterinary Journal we were advised to use a more scientific name, so we coined the rather unimaginative term “chronic udder oedema”. These cows had a persistent thick swelling at the base of their udders which, once it had formed, would never go away and could be bad enough to interfere with their ability to release milk. The thickening tended to worsen with each season, and leatherbag cows usually had to be culled prematurely.
Our paper seemed to trigger some interest. The reference ranges the animal health laboratories recommended for serum magnesium levels in cattle were raised, and some veterinary scientists descended on us with blood tubes and sample pottles and co-opted me to take them onto the worst affected farms. The pottles were for urine. There was a new test to measure the concentrations of magnesium in urine. It’s easy enough to suck the blood out of the tail vein of a cow, but how do you make a cow urinate on demand? Once again, the doctors have it over us vets…
It requires some patience, but if you rhythmically rub the skin beneath a cow’s vulva she will generally oblige. It’s not the sort of thing you want to be found doing without good reason. It could be quite time-consuming and there was always the odd cow that wouldn’t release. Invariably we were the butt of ribald comments; farmers never let vets off the hook if they can help it: “If you carry on like that she’ll be doing you for harassment!” Sometimes you had to give up, or try again later and sometimes there were accidents. There I was, stroking away, my mind on some higher plane, when a cow lifted her tail and filled my gumboots… but not with urine. The old farmer gave me a wry smile: “Must have pressed the wrong button there, son.”
By this stage many farmers were finding that if they supplemented their cows with magnesium during spring, their cows were generally less nervy, easier to milk and gave more milk. They also had fewer occurrences of full-blown grass staggers. Over the next few years most New Zealand dairy farmers adopted this practice and, these days, not only are there some very sophisticated automated systems to deliver magnesium supplements to dairy cows, but there is also a far greater understanding of the interactions between minerals in the soil and pasture and the need to be cautious about the timing and rates of application of all fertilizers, but especially potash.
I like to think that John and I contributed a small amount to the understanding of a topic which had such important implications for New Zealand’s dairy industry; for, as Blood and Henderson stated: Tetany associated with depression of serum magnesium levels is a common occurrence in ruminants, but probably in no other disease of domestic animals is there as much confusion in relation to aetiology and pathogenesis as there is in this group of diseases. The position is made even more confusing by the variety of circumstances in which they occur, and by their common association with other metabolic and nutritional deficiency diseases.
My rewarding early experience of trial work encouraged me into further scientific trials on farms later in my career. It was especially enjoyable to work alongside farmers who were willing, often at considerable inconvenience and cost, to provide their animals and time for the greater good and the cause of science. Many of these investigations revealed the worthlessness of supplements peddled unethically to farmers, for whom the real answers usually lay in improved management and better nutrition. Apart from the provision of essential trace elements, where they are known to be deficient, and controlling internal parasites, the three most important things contributing to healthy and productive livestock remain – as we were so strongly advised as students – feeding, feeding and feeding.
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My copy of Blood and Henderson was inscribed by my fiancée: Darling John,
for our engagement… with all my love, Viv. That was the start of her lifelong commitment to my career, as was the case for so many vets’ wives of that and previous generations. My Blood and Henderson was brand new and expensive, the up-dated edition being then too recent for second-hand copies to have yet found their way into the student bookshops. To some it would seem an unromantic gift. But Viv had invested her hard-earned money in my future, in my passion to be a vet. No present could have thrilled me more.
It is strange how the passions that drive us change. Many people retain their passions for their careers, sometimes at the expense of that for their partners. For me it was the other way round. Failed marriages are a hazard for vets as much as anyone else, but the current growing disaffection of vets for their profession is not talked about, nor expected by the general public, who are still mislead by Herriotism. This is a term coined by modern vets to describe the legacy left by the brilliant novels of James Herriot and his romanticised depiction of veterinary practice in the 1930s. Some aspects of Herriotism survive in modern veterinary practice, but social changes have ensured his model of life as a vet has all but vanished. One of the reasons why so many young vets are abandoning their profession early is that the idealised perceptions they harbour as young undergraduates do not match up with the reality they now find behind the farm gate.
I have to confess that I embraced the James Herriot myth for all it was worth. I feel lucky that I was born in an era where I could be that sort of vet – well, some of the time. For the most part of my working life I couldn’t imagine doing anything else or, perhaps more importantly, being anything else. Being a vet was my identity.
But, against the immense satisfaction vetting generally brought me, there were certainly some doubts and darker moments.
Chapter Twenty-five
The Seeds of Doubt
The bond between a man and his profession is similar to that which ties him to his country; it is just as complex, often ambivalent, and in general it is understood completely only when it is broken: by exile or emigration in the case of one's country, by retirement in the case of a trade or profession. – Primo Levi
I looked at the handwritten envelope in front of me. I didn’t recognise the writing. It was early January: a delayed Christmas card? Well, not exactly. It read “I hope you have a lousy New Year”. An attached letter explained that the dog I had recently treated had since died, “thanks to you”. It was signed “yours hatefully, Buddy”. (Not his real name!)
I only had to think back a few days to recall Buddy. I had been called out on Christmas Day to see his Boxer dog, Fritz, who had suffered a sudden bout of vomiting and diarrhoea after eating some fish bait. When I examined him, Fritz had been a bit subdued, as could be expected, and I had treated him for a routine gastro-enteritis, a diagnosis consistent with the history and presenting signs. I always made it a policy not to assume that my patients would automatically recover from my treatments, so I did warn Buddy to get in touch if Fritz didn’t get better or, more importantly, if he deteriorated.
Buddy, a fisherman, had been thrilled that I could see him at such short notice. Both he and I were unable to contact his usual vet. After I had attended to Fritz he had even talked about dropping off some crayfish for me and we parted on warm terms.
Until I received this entirely unexpected and obnoxious card I had obviously been deluded in my assumption that Fritz had made an uneventful recovery. Whereas, the letter continued, when Fritz collapsed the next day Buddy had… taken him straight round to his usual vet [the one he was unable to contact on Christmas Day], who told him that Fritz had kidney failure and that if only he had seen Fritz earlier he would have been able to save him. How could he be so sure?
Apart from the upset of Fritz’s death I felt betrayed by the other vet. He could have had only the vaguest idea of what I had done for Fritz. His throwaway comment may have been purely to promote his own abilities but he was, by implication, denigrating mine. Was he also aware that he had sown hatred in the mind of Fritz’s owner? As a registered vet he should have been aware of his ethical obligations and known that the correct procedure should have been to contact me and find out more about my diagnosis and treatment so that he could tailor his more effectively. It was a blatant case of “supersession”.
The internal workings of the professions are subject to great suspicion by those who regard them as stuffy, protectionist and anti-competitive, but they would be re-assured if they read the Code of Professional Conduct to which vets are supposed to adhere. It is largely concerned with maintaining standards of care and competence:
Veterinarians must take into consideration the risks of treating an animal without first ascertaining from the original veterinarian the initial diagnosis and details of any treatment prescribed. Making such enquiries will normally safeguard the interests of the animal, the legal position of the veterinarians concerned and enable the professional courtesies implicit in this rule to be observed.
If it is discovered during the course of a consultation that the patient has been in the care of another veterinarian for the same reason, then the latter should be notified as soon as possible after the consultation. The welfare of the animal must be the overriding consideration under all circumstances.
The unfairness of Buddy’s accusation certainly upset me and it did result in repercussions for his vet. It wasn’t the first time he had trodden on our toes. I had good records of my clinical work-up for Fritz, and I forwarded them plus my “greetings” card to the New Zealand Veterinary Council. I felt vindicated when the vet concerned was censured for his unethical behaviour.
Ever since the Veterinary Surgeons Act of 1881, veterinary surgeons could, theoretically, be removed from the Register for “disgraceful professional conduct”, but to begin with, the Council of the Royal College of Veterinary Surgeons could not decide what constituted such an offence. They initially jumped on advertising, always a contentious issue for vets. By 1890 there was acute competition between veterinarians. Times were hard and vets were distributing circulars offering cut-price services. The Council then received a complaint about one member who was promoting his services and nostrums by blowing a hunting horn in the local marketplace. It may sound colourful and quaint to our ears, but this was regarded as a flagrant case of unprofessional advertising and in 1894 advertising became the first item listed as “conduct disgraceful in a professional respect”.
These days the Commerce Commission would almost certainly protect the rights of the horn blower against any edicts from his profession, but this is a relatively recent change of opinion. For much of my career advertising was strictly proscribed. It was felt preferable that your abilities be promoted by word of mouth. Most vets were reasonably happy with that, because it freed them to concentrate on providing a good service rather than waste their energy blowing horns. But there has always been the counter argument that the profession needed to lift its profile, promote itself, and inform the public about the wide range of services it offers. Over recent years, veterinary practices have grown bigger and their staff less stable; their clientele is also more mobile, displays less loyalty and shops around for the best deals. If you want to compete you have to advertise. Vets who find the new ethos personally distasteful can always employ others to run their promotions. We have reached the stage where many practices employ CEOs and run advertising budgets. So the Code has been modified and advertising is now sanctioned, a cause lost or won, depending on your point of view; but there are many other pitfalls in the Code for the maverick vet.
Most veterinarians employed in western countries will glance, gloat or shudder through the reviews published by their respective disciplinary bodies. There, paraded as a warning for all to heed, are the misdeeds of those miscreants who have, in the opinion of their peers, stepped over the boundaries. This could be for a variety of offences: drug addiction, supplying false certification, professional negligence or straight incompetence. The worst transgressors are “struck off
” the Register – their means of livelihood removed for varying periods of time.
I felt the most sympathy for a British vet who was severely censured by the Royal College of Veterinary Surgeons for killing a hamster. He picked the unfortunate animal from its cage and – I can imagine his instinctive reaction when the little creature bit him on the thumb – flicked it off, unfortunately killing it in the process. It must have been the way he performed this “highly unprofessional” manoeuvre that resulted in the owner laying a complaint. I can almost hear the profanity exploding from his lips. So many disciplinary cases proceed through lack of communication or empathy. A heartfelt apology by the “hamster thug” at the time may have prevented a lot of anguish and expense, but maybe he was unlucky enough to strike a particularly obdurate owner. I can’t recall if he took up his right of appeal to the Privy Council but, if he had, it would have ended up as an extremely expensive hamster.
The dispensing and sale of dangerous or restricted drugs is another contentious area. What does an assertive farmer or horse owner care for professional ethics? There will always be those who attempt to browbeat vets into supplying inappropriate antibiotics for food producing animals, or anabolic steroids to make a winning horse out of a loser. The vet who takes a firm ethical stand risks condemnation for being officious and losing business for his employer. The lax vet gains friends and attracts business at the risk of alienating his colleagues and facing disciplinary action. Vets’ obligations to the national interest – in matters such as biosecurity, the prevention of drug residues in animal products and to police animal welfare infractions – override any obligation to keep a client happy. Striking a balance between ethics and pragmatism was never easy, but it has become increasingly stressful: especially for young vets at the start of their careers.