I’ve been looking at the Irish annals for references to plagues and I came across a couple of references to cattle plagues. Now these plagues are probably not the same disease causing human deaths in the annals. There is a species barrier for most diseases, but not all. Yersinia pestis is one that can cross the species barrier but I don’t think cattle are frequent plague victims in large numbers. Further, if humans were also victims they would be mentioned more prominently in the entries.
More importantly, cattle plagues cause human famines and protein malnutrition that can last for a decade or more. A massive loss of cattle can’t be replaced in a year or two. You can’t just order up replacement cattle. I was at a talk last year at Kalamazoo where they showed that the cattle plague that preceded the beginning of the Black Death took nearly 20 years for cattle stocks to recover. This caused a full generation of protein malnutrition. I would also add that milk would have also supplied a considerable amount of fat in the diet. We have too many fats in our diet today but in a medieval diet, milk fat (in butter, cheese and whole milk) would have been a significant dietary resource. Where else would a medieval diet have gotten protein or fat? With a short supply of cattle, there would have been little meat available (leaving probably mostly pigs, sheep, and birds for meat). Under normal circumstances milk and eggs would have supplied a significant amount of protein. This would have left people relying very heavily on carbohydrates for all their nutrition. Its hard to get a enough protein from vegetables alone. Eggs would have become a critical protein source.
This all reminds me of Bede’s claims that the Irish monks relied heavily on cattle. On Lindisfarne, they drank only milk and water. He claimed that St Cedd fasted at Lastingham eating only a little bread, a hen’s egg, and watered milk. Likewise St Egbert fasted on only a little piece of bread and skim milk. The Irish could survive quite healthily on just milk and cereals. Milk supplies protein, fat and sugar. Cereals supply carbohydrates. There are your four basic food groups, if not a lot a variety. However, this leaves them highly reliant on one type of animal and a cattle plague/murrain could be disastrous.
The Annals of Ulster record that the cattle murrain starts among the Saxons in 699 and it appeared in Mag Trega in Tethba (Ireland) on the Kalends of February in 700. Mag Trega is Moytra in County Longford, Ireland. It then records also in 700 that “famine and pestilence prevailed in Ireland for three years, so that man ate man.” Obviously this is a retrospective entry for it to list that it occurred for three years. Nevertheless, it illustrates how dependent the Irish were upon their cattle. The Annals of Ulster recorded a mortality of cows again in 701. It wasn’t over yet. Again in 708, another cattle murrain is recorded.
The cattle plague would also seem to suggest that there was some trade in cattle across the Irish Sea. The annalist recorded the cattle deaths beginning among the Saxons, then spreading to Ireland. We also have to keep in mind that cattle were wealth certainly in Ireland, but perhaps also in Britain. We are left to wonder what political ramifications resulted not only from the famine and deaths but from the loss of cattle wealth. Would this have made cattle raiding more fierce over the cattle that were left, or would elites look from something else by which to calibrate their relative wealth? Could this have led in part to an increase in coinage at the turn of the 8th century? What could have replaced cattle (or leather) as a trade good? Remember it can take 10-20 years for cattle stocks to recover have a major cattle plague.
I looked at all the entries from 650 to 730 and these are the only cattle deaths mentioned. The human plague reports and the cattle deaths are distinct. The pestilence recorded that accompanied the famine in c. 700 was probably gastrointestinal since in such a severe famine people would have been eating anything they could find. Scavenging for food coupled with a lowered immune response makes people very vulnerable to food poisoning / intestinal disease. Weakened immune responses could have also led to a variety of infectious diseases striking the population, much as they do in refugee camps. Between the human plagues that struck in the 660s and 680s, and the cattle plague at the turn of the century every generation in the second half of the seventh century would have coped with illness and death en masse.