EUGENE M. MCCARTHY, PHD GENETICS
And so if, as you recently told me, a lamb with a pig's head was born, then it is because a pig mated with a sheep.*
Dialogues On Prodigies, III, xxvi
Note: This disparate cross requires further confirmation.
The occurrence of pig-sheep hybrids is often alleged in the media. And it’s well documented that sheep and pigs will mate (YouTube videos document both boars mounting ewes and rams mounting sows). It’s a common barnyard occurrence. But can they produce hybrids?
In 2010 stories about woolly sheep-like pigs and sheep-pig hybrids surfaced on the internet because a zoo in the UK (Tropical Wings Zoo, South Woodham Ferrers, Essex) announced that it had imported rare “Mangalitza” pigs (see photos) and that they planned to breed them. Many people thought they were sheep-pig hybrids. As a BBC story reports:
An extremely rare breed of curly coated pig is to be bred for the first time at a zoo in Essex.
The three Mangalitza pigs, which bear a striking resemblance to sheep, arrived at the Tropical Wings Zoo in South Woodham Ferrers, just before Easter as part of a programme to save the breed.
“At first sight people perhaps think they are sheep” said education co-ordinator Denise Cox.
“It’s not until they turn around and you see their faces and snouts that you realise they are in fact pigs.”
The breed is thought to be native to Austria and Hungary.
The BBC makes no claim that these animals are sheep-pig hybrids, only that they are a “rare breed” of pig. But how did these pigs obtain a fleece like a sheep's? It seems it would take some very clever breeding to start with a near naked, bristly pig and somehow select for a dense sheep-like coat of hair. And it seems no genetic study of these “pigs” has been made. And after seeing this story, a Spanish geneticist whose former lab sequenced the genomes of some Mangalitza pigs said that, although the results of the study had been compared to other breeds of pig, he did not think any comparison had been made to sheep. So it really must remain a matter of opinion whether they are hybrids or not, although it’s clear from comments on the various stories around the internet that many people think they are.
Another possibility to consider is that the pictures of these animals have been faked. But if so, it would mean the BBC was duped, because at the time this article was written (Oct. 16, 2014), the photo at the top of this page had been on the BBC's website for more than four years. However, the same Spanish geneticist mentioned in the previous paragraph, an eyewitness who seems to have no reason to lie, confirmed that the picture at the top of this page is not a fake and that it does accurately show the appearance of these animals. He did, however, say there was a good bit of variability among individuals. He also said that he personally did not think they were sheep-pig hybrids, though he admitted no study had been done.
If these bizarre animals do in fact exist, they should certainly hurry to the nearest lab to have their DNA compared with that of a sheep!
A sheep-pig hybrid would be an interfamilial cross, since pigs belong to Family Suidae while sheep belong to Family Bovidae (although both are artiodactyls). Other mammalian interfamilial crosses have been reported, so such a hybrid does not seem entirely out of the question.
Perhaps prompted by the article above, the BBC has recently published two brief stories on “Mangalitza pigs” (and in these new articles, by the way, they are now using the spelling “Mangalica”).
One of these articles, by BBC World Service broadcast journalist Lucy Hooker, is about efforts to save the breed. In that article she comments that “To the uninitiated it is a sheep-pig. In reality it is the Mangalica, a comical but appealing breed that is taking the food industry by storm.” What this comment fails to recognize is that it is well known that many breeds of domestic animals are originally derived from hybrid crosses. I discuss this fact at length, among other places, in my reference work on hybridization in birds (Handbook of Avian Hybrids of the World, Oxford University Press, 2006) and elsewhere on this website. So really, it's entirely possible that these pigs are not only a breed, but also of hybrid origin. The two are by no means mutually exclusive as Ms. Hooker seems to suggest.
Since this is an old breed, which has apparently existed for centuries, its origin seems to be unknown. To determine the nature of that origin, it will be necessary to carry out investigations. One obvious way of gaining information about whether these animals might be sheep-pig hybrids is genetic analysis, as mentioned above. Another is experimental mating to see whether such hybrids can be produced. It is even conceivable that breeding records survive describing how the breed was produced (as is the case with many domestic breeds derived from hybrid crosses). Certainly, there are reports about sheep-pig hybrids being produced in Mexico (see below).
But the BBC's implication that only the uninformed would suppose that these animals might be sheep-pig hybrids (i.e. “To the uninitiated it is a sheep-pig.”) seems premature. I am a geneticist and a leading expert on hybridization, and yet I think they might be hybrids of that sort, though I would never make such a claim without firm evidence to substantiate it. Moreover, I gently object to Ms. Hooker's statement. It treats the unknown as known and therefore tends to dampen the spirit of investigation.
The other article, which is very short, was written by Tim Muffet, a reporter for BBC Breakfast. It's really just a bit of text to accompany a video showing how these pigs are being used to restore heath land. From the standpoint of the sheep-pig question, this video is of interest primarily because it demonstrates beyond doubt that animals, such as the one pictured at the top of this page, do actually exist. Mere pictures can easily be faked. Videos, especially videos from a reliable source like the BBC, cannot.
The video evidence is also relevant because individual variation can be seen in the animals shown, with some looking identical to the very sheep-like animal shown above with its curly white fleece, to animals with sparser straight, black pelts more similar to that of European boars. This is exactly the sort of variation that occurs in a wide variety of hybrid crosses, where some individuals are more similar to one of the two parents that originally crossed to produce them, while others are more similar to the other. Such variation is especially characteristic of later-generation hybrids, the descendants of the first-generation, or F₁, hybrids produced by the original cross.
In the video accompanying Ms. Hooker's article, it can also be seen that these animals have dark red meat like that of a sheep, not the light-colored meat typical of most pigs.
In his book Swine in America: A Textbook for the Breeder, Feeder & Student, Foster Dwight Coburn (1846-1924), a US farmer and government official who served as secretary of the Kansas Department of Agriculture, states the following about an animal known as the cuino, once (and perhaps still?) bred in southern Mexico (Coburn 1916, pp. 63-64):
There exists in some sections of Old Mexico a type of “hog” represented as the product of crossing a ram with a sow, and the term “Cuino” has been applied to this rather violent combination. The ram used as a sire to produce the Cuino is kept with the hogs from the time he is weaned. A resident of Mexico has given the following description of the Cuino: “The sow used to produce the Cuino belongs to any race, but as a rule to the Razor-Back family, which is the more numerous. There is never any difficulty with her accepting the ram when breeding time comes. The progeny is a pig—unmistakably a pig—with the form and all the characteristics of the pig, but he is entirely different from his dam if she is a Razor-Back. He is round-ribbed and blocky, his short legs cannot take him far from his sty, and his snout is too short to root with. His head is not unlike that of the Berkshire. His body is covered with long, thick, curly hair, not soft enough to be called wool, but which nevertheless he takes from his sire. His color is black, white-black, and white-brown and white. He is a good grazer and is mostly fed on grass with one or two ears of corn a day, and on these he fattens quickly. The Cuino reproduces itself, and is often crossed a second and third time with a ram. Be it what it may, the Cuino is the most popular breed of hogs in the state of Oaxaca, and became so on account of their propensity to fatten on little food.”
So could it be, then, that the BBC and UK zoo where the “ancient Mangalitza breed” is being “preserved” (see above) have simply been duped, and these hybrids are being passed of by hucksters as a rare breed? Judging from Coburn’s comments, it does seem that such a possibility should be considered.
Coburn clearly assembled this passage from extracts taken from a longer article, entitled “The Cuino, A Curious Cross,” by Roger de La Débutrie (1863-1924) that appeared in another agricultural publication, the Southern Planter and Farmer (Débutrie 1900, p. 513). Débutrie’s article, which originally appeared in the respected journal The Breeders’ Gazette, reads as follows:
In a recent letter to the Gazette in relation to mule-footed hog, I mentioned the cuino, the product of a cross between a ram and a sow. Requests for particulars as to this animal have been received and I give them with pleasure. The information, however, must be very incomplete, I know, and unsatisfactory on many points, but I beg to be excused on account of the great difficulty of gathering data in this country [Mexico], the inability of most people to give satisfactory explanations from want of knowledge or observation, and the lack of any attempt to experiment in any form.
|Location of Oaxaca|
The cuino (pronounced queeno) is not considered a special race of hogs, but a hog of any race which has been improved, refined, by the introduction of sheep’s blood. I do not know if the cuino is bred in all Mexico, but he is to be met with all over this State, in the mountain districts as in the extensively cultivated valley of Oaxaca.
The ram used for crossing on sows belongs to the ordinary well-known, long-legged, light bodied Mexican sheep. He must be polled, and if not he has to be dehorned for fear he should hurt the sows. No pains are spared in his training, which begins at an early age; in fact, as soon as the lamb is weaned. When able to eat, he is taken away from his mother and the flock, and from that time forth has to live entirely in the company of hogs, never being allowed to see any of his own kind. He is pastured and fed with the drove of pigs and sleeps with them at night. With such an education and training he can not but believe himself a pig as well, and, when the time comes, has no objection to serving the sows. When the sow is in heat, he is shut up with her in a narrow pen and left as long as judged necessary. If he is slow in serving her, he is given an aphrodisiac composed of roast maize and salt, which always settles matters. This roast maize and salt is also used for this purpose in Mexico with other animals like the jack when slow in serving. The sow used to produce the cuino belongs to any race, but, as a rule, to the razor-back, which is the more numerous. There is never any difficulty of her accepting the ram when breeding time comes.
The progeny is a pig—unmistakably a pig; he has the form and all the characteristics of the pig, but he is entirely different from his dam, if she is a razor-Back. The sow in that case is, as you know, long legged, flat-ribbed heavy boned, with an immensely long snout. She runs miles from the ranch, foraging in the bush, where she is too often the prey of the leopard or the puma. She can put away bushels of corn without any appreciable effect on her carcass; in fact, I need not describe her, she is well known in your Southern States. Her pig is entirely different; He is round-ribbed and blocky, his short legs cannot take him far from his sty, and his snout is too short to root. His head is not unlike that of the Berkshire. His body is covered with long thick curly hair, not soft enough to be called wool, but which, nevertheless, he takes from his sire. His color is black, white, black and white or brown and white. He is a good grazer and is mostly fed on grass, with one or two ears of corn a day, and on these he fattens quickly. I have seen the litter of a mule-footed sow bred to a ram; her pigs were either single hoofed or cloven footed, about half of each kind.
The cuino reproduces itself, and is often crossed a second and third time with a ram. One of my neighbors, who breeds cuinos on his ranch, told me that it requires two or three introductions of ovine blood to produce a highly improved race of cuinos. I asked him if by breeding the cuino a number of times over again to a ram the progeny would not have more of the form and characteristics of the ram. He answered tha the progeny would always be hogs. Then I made the objection that, in such a case, he might, after a number of crosses, have a hog practically a pure blood sheep. To that he made no answer, only laughed.
Be it what it may, the cuino is the most popular breed of hogs in this State of Oaxaca, and became so on account of his propensity to fatten on little food.…I do not suppose any of the readers of The Gazette will ever want cuinos, having such excellent breeds of hogs, but they may like to know something about the ways of their Mexican neighbors and the extraordinary cross that produces the cuino.—Roger de la Débutrie, Huautla, Oaxaca, Mexico, in The Breeders Gazette.
A reader subsequently wrote in to the Breeder’s Gazette (1906, vol. 50, p. 836; see also: The American Veterinary Review, 1906, vol. 30, p. 1123) about the cuino. His letter and the Gazette’s response read as follows:
In connection with the information just given, it’s of interest that a book published by the Mexican government on the geography and statistics of Zacatecas (Geografía y estadística del estado de Zacatecas, 1894), a state that borders Oaxaca on the south, lists among the principle animals of the state (“los principales animales que viven en el Estado”) the Cerdo Cuino, giving it the name Sus hybridus, and stating, too, its origin, as follows: “Proviene de la unión del carnero con la puerca” (“Derived from the union of a ram and a sow”).
The following is the translated text of an article that appeared in the Revista ibero-americana de ciencias médicas (1903, vol. 10, pp. 230-231) (Spanish-American Journal of Medical Sciences):
Hybrid between pig and sheep, which is known as the cuino in the Central Plateau [of Mexico], by Dr. Otón Efferd, physician at the Hospital of Mihuatlán, Oaxaca, and former resident physician at Puerto Angelo.
When I arrived in the district of Pochutla, Oaxaca, a few years ago, the inhabitants informed me that certain pigs, which differed externally from ordinary pigs, were the offspring of a ram mated with a sow, and that they were called cuinos.
At first I laughed at the zoological impossibility of this claim, and by my incredulity lost some of my scientific reputation among the inhabitants of this region. But accumulating, little by little, information about the reality of these crosses, I gained the opportunity of verifying the facts of the matter with my own eyes.
These crosses are only produced in regions with a moderate climate, since rams cannot stand climates that are too hot. It's extremely hot in Pochutla. So the closest place to Pochutla where they produce these hybrids is Mihuatlán, which is a three-day journey on horseback.
In March of last year, I asked for leave and traveled to Mihuatlán. Very quickly, I convinced myself there that these crosses are almost certainly real.
The thing that convinced me was the fact that there are many individuals who do business renting their rams to the owners of sows. The Indians are such sage observers of daily life, and so tight with their money, that it is difficult to conceive of one of them paying even a single penny to these ram owners for nothing.
The economic motive for these crosses is that “cuinos” fatten more easily than do conventional pigs.
When I got back to Pochutla I communicated my observations to a dozen laboratories, in both the old and new worlds, inviting them to send a specialist to carry out experiments and research with regard to these revolutionary hybrids. But they all replied that this cross was an absolute zoological impossibility, that I was the dupe of Indian fables and that it wasn't worth the bother of sending a specialist to verify things that cannot exist.
Having lost all hope of convincing a zoologist, I decided to carry out studies of my own. I resigned my positions at Pochutla and Puerto Angel, and moved to Mihuatlán forthwith.
Six weeks ago, my research into “cuinos” began. To conduct these experiments in such a manner as science truly requires would take six months. However, I am curious to know what the comments of my colleagues in the Central Bureau of Mexico might be with regard to these hybrids. People here say that these crosses are made in many parts of the Central Plateau.
If any of the readers of this journal would like to assist me in this research, which will, if the results are positive, certainly revolutionize the theory of evolution, it would be much appreciated. (From the School of Medicine of Mexico) [Translated by E. M. McCarthy. Original Spanish >>].
The following news report about a Mexican sheep-pig hybrid appeared on page 12 of the October 3, 1908 issue of the Los Angeles Herald (source).
The following report about a sheep-pig hybrid that appeared on page 13 of the September 24, 1902, issue of The Minneapolis Journal, a newspaper published in Minneapolis, Minnesota (source).
The following report about a sheep-pig hybrid is of interest because it speaks of a hybrid produced from the reverse cross (ewe x boar). It appeared on page 13 of the September 24, 1902, issue of The Minneapolis Journal, a newspaper published in Minneapolis, Minnesota (source).
The next article also reports the cross in the “wrong” direction. It appeared on the front page, column 6, of the August 7, 1908, issue of the Ripley County Democrat, a newspaper published in Doniphan, Missouri (source). It originally appeared in the Caruthersville Press, a newspaper published in Caruthersville, Missouri.
The following report appeared on page 4 of the January 6, 1888, issue of The Ogdensburg Journal, a newspaper published in Ogdensburg, New York (source). The original report appeared in the Binghamton Republican
The French Renaissance surgeon and anatomist Ambroise Paré (1646, p. 665) mentions that “there has been seen a lamb having the head of a pig, because a boar had covered a ewe.” Translated by E. M. McCarthy. Original French: “Il s’est veu un agneau ayant la teste d’un porc parce qu’un verrat avoit couvert la brebis.” Paré’s comment may refer to an assertion made by Livy (The History of Rome, Book 31, 6), the ancient Roman historian, who says that “at Frusino [modern Frosinone, in central Italy] a lamb was yeaned with a head like a pig.”
A sheep with the head of a pig? A rather apt description of the animal pictured at the top of this page!
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* Translated by E. M. McCarthy. Original Latin: Ac propterea nuper narrasti agnum suillo capite insignem natum, quod verres iniverit ovem.