Why is aspirin toxic to cats? One animal’s cure can be another animal’s poison. Take aspirin – it’s one of the most popular drugs on the market and we readily use it as a painkiller. But cats are extremely sensitive to aspirin, and even a single extra- strength pill can trigger a fatal overdose. Vets will sometimes prescribe aspirin to cats but only under very controlled doses. But these fountains of youth. DIET & FEEDING (Bodmer & Gubista 1988) (Bodmer & Rabb 1992) (Crissey et al 2001) (Hart 1992) (Hart & Hart 1988) Highly selective feeder on leaves, fruits, seeds. Home > Marine Invertebrates > Invertebrates for Beginners: Invertebrates for Beginners These are marine invertebrates proven to be hardy, undemanding, and well-suited. Whether you're looking to train a new puppy, find the best toy for your cat or set up a tropical aquarium, eHow has answers to all of your pet-related questions. We think of them as slovenly, gluttonous creatures who are content to roll around in their own. If you’ve ever been duped by a phishing scam, you can feel a little less stupid about it today, because you’ve been joined in that sad club by Google and Facebook. The problem is that cats can’t break down the drug effectively. They take a long time to clear it from their bodies, so it’s easy for them to build up harmful concentrations. This defect is unusual – humans clearly don’t suffer from it, and neither do dogs. All cats, however, seem to share the same problem, from house tabbies to African lions. Now, Binu Shrestha from the Tufts University School of Medicine has found that cats may have developed their strange sensitivity because of their lifestyle as specialist hunters. Their penchant for meat could have ultimately turned aspirin into their kryptonite. Our livers break down aspirin using a protein called UGT1. A6, encoded by a gene of the same name. In 1. 99. 7, Michael Court, who led Shrestha’s study, showed that the cat version of this protein is barely produced in the liver. Three years later, he found out why – the cat genome has a broken version of UGT1. A6. The gene has been riddled with crippling mutations that prevent it from producing a working protein, like a recipe with missing and garbled steps. In technical terms, it’s a “pseudogene”. This is an old problem. Shrestha looked at the gene in 1. Several lineages had accumulated more. The common ancestor of all modern cats must have been just as sensitive to aspirin (or more realistically, similar natural compounds) than our house cats. But this problem isn’t limited to cats. Shrestha checked the state of UGT1. A6 in other carnivores, and found two other species – the brown hyena and the northern elephant seal – that also had busted versions. Also, what is wrong with you?)The gene was active and serviceable in other groups of meat- eaters, including the other three hyenas, dogs, bears, mongooses and racoons. What sets the cats, the seal and the brown hyena apart? Shrestha thinks it’s their diets. Whether or not a turtle is a carnivore, a herbivore, or an omnivore really depends on the particular species. For instance, tortoises are almost always exclusively. The telescope, in Kuntunse near Accra, is the first of an array of such instruments expected to be built across Africa over the next five years, and forms part of. The ImmunoStar serotonin antiserum was quality control tested using standard immunohistochemical methods. The antiserum demonstrates strongly positive labeling of rat. Also, what is wrong with you? Why must I be tarred with the epithet “Loony” just because. These species are all “hypercarnivores”, meaning that meat makes up more than 7. By comparison, bears and dogs are “mesocarnivores”, meaning that they eat some plant food too. Like many other “detoxifying” proteins, UGT1. A6 evolved to help animals cope with the thousands of dangerous chemicals in the plants they eat. For animals that eat plants, even on an irregular basis, these genes are a boon. Individuals with broken copies would be forced into narrower diets and lose out to those with working copies. But if an animal’s menu consists largely of meat, it has little use for these anti- plant defences. The genes are dispensable. Individuals with broken versions can survive just as well as those with working ones, so the broken genes spread through the population. In this way, the ancestral cats gradually built up mutations that disabled their UGT1. A6 gene. Evolution is merciless that way – it works on a “use it or lose it” basis. UGT1. A6 isn’t the only gene that’s gone through this fate. Cats also have low levels of amylase in their saliva, and enzyme that starts breaking down carbohydrates. And unlike many other mammals, they don’t have a sweet tooth because their copy of Tas. Both events might also have been the result of their move away from plant foods. That’s not the whole story. Other hyenas, mongooses and weasels also count as hypercarnivores, and their copies of UGT1. A6 work just fine. This means that a meat- heavy diet might predispose animals to inactivating their copies of UGT1. A6, but it isn’t the only factor behind the gene’s downfall. And Shrestha has an idea what that might be. Modern cat families evolved from a common ancestor around 1. Before then, there’s a bizarre lack of cat fossils – a so- called “cat gap” that lasted from 2. It’s possible that during that time, cats passed through a “genetic bottleneck”. Their populations were small and any mutations within the surviving few were passed on to their descendants, including the faulty version of UGT1. A6. It’s probably no coincidence that the northern elephant seal has also recently gone through a similar bottleneck. Reference: Shrestha, B., Reed, J., Starks, P., Kaufman, G., Goldstone, J., Roelke, M., O’Brien, S., Koepfli, K., Frank, L., & Court, M. Evolution of a Major Drug Metabolizing Enzyme Defect in the Domestic Cat and Other Felidae: Phylogenetic Timing and the Role of Hypercarnivory PLo. S ONE, 6 (3) DOI: 1.
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