Bucks with Bags!
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Yes, you read that right! Bucks can have udders — and some even produce milk!
While it may seem unsettling — even freakish — it isn’t new or even rare. Anecdotal stories go back for decades. The condition is called gynecomastia, and it happens in many mammals. Not much research has been done on goats, and the information is limited — unless you talk to goat owners, particularly high-production dairy breeders.
Many react to their first glimpse of a buck udder with alarm, as Suzanne Devine’s husband did, seeing their Nubian buck, Goggles, standing up against the gate at Freedom Hollow Farm in Tennessee. “He is such a freak; look at his teats! What is wrong with him?” Suzanne had no idea, so she called their vet, who was also puzzled. Interestingly, while the condition appears in herds worldwide, a search for gynecomastia in the Merck Veterinary Manual returns no results. Suzanne reached out to her breeder, who confirmed that she had seen it many times. It was strange, yes, but nothing serious.
Annabelle Pattison of Veteran’s Ranch in Arizona began raising goats 12 years ago. One of her original bucks developed an unusually large teat, but she wasn’t surprised. While many aspects of goat raising were new to her, this wasn’t. She had seen it before in a friend’s herd. It is widely believed that bucks with udders come from the milkiest lines. And there is a genetic component. Her friend owned Galaxy Noel’s Comet, whose dam has been a five-time ADGA Top Ten doe. Comet’s daughters — full sisters from the same litter — were three times in the Top Ten. Comet is still in the top five individual bucks on the USDA Elite Sire list, and he has been gone for four years! Annabelle has several bucks with large teats in her Nubian herd and one with a “ginormous udder:” Crow’s Dairy Little Richard, son of Comet. Few bucks are kept to the age of three or older in the dairy world to know the exact genetic prevalence of the trait, but Annabelle knows of at least three sons with udders. Breeders can confirm with pedigrees that it runs in lines.
You may hear that, if a buck has a pendulous or split scrotum, it spells disaster for his female offspring’s udder. Looking at Little Richard, we can see that the scrotum and scrotal attachments’ anatomy is entirely different from that of the udder since he has both. To determine the heritability of udder traits, look at the buck’s udder, and if he doesn’t have a fully developed udder, look at the dams in his line.
Do the bucks produce milk?
Yes! Some do. Cobie Woods of Milk House Goats, Kamloops, BC, Canada, can testify. They had isolated a buck, Haldibrook Kroosader, and had some recently weaned bucklings that were separated from their dams. The bucklings were trying to steal from other dams when they happened upon her buck and found an udder! The buck stood, the kids nursed, and their little tails were wagging and lips smacking — signs of satisfaction. She was curious if it was actually milk, so she squeezed his teats and both secreted milk easily, no different from a doe. “I smelled it, and it seemed just like milk; white, thin, no smell, no chunks or stringiness. I was never brave enough to taste it.” She has also seen a genetic component as his maternal sire, and a son, both produced milk.
Most owners do not milk their bucks as milking encourages production. It is rumored that Thrill, a LaMancha buck from Lucky Star Farms in Washington, was put on test, completing all 305 days and producing 3,261 lbs. I wanted it to be true! A quick fact-check with the owners dispelled the rumor. He did produce milk but was never put on test.
What brings a buck into milk?
Just as others report, Kroosader’s teats began to swell the summer he was two years old. They subsided a bit but then got more prominent in his third summer and remained full. They follow a cycle, getting larger and tighter in the spring/summer months on pasture. Many breeders notice their buck’s udder getting fuller in rut, but oddly enough, it doesn’t interfere with breeding.
Can bucks develop mastitis?
They can. Any udder can develop an infection, and milking udders run the highest risk. Dawn Kirby and her family own Lucky Run Farm in Maine. Their milking buck, Fox’s Pride NASC Corona, has not had problems, but she considers the possibility and checks him regularly. Bucks that develop bags do not seem to dry up as thoroughly as does do, and some not at all, so their owners remain vigilant. Bucks can, and have, died of undetected mastitis infections.
Are bucks with bags fertile?
Many are; some are not. There is concern that the warm udder against the testicles would raise the temperature and result in sterility. Dawn assures us that her buck is very fertile. He has settled every doe he’s bred on the first cycle. None of the breeders interviewed reported any issues. These bucks have all lived up to the reputation of bucks with bags: producing exceptionally milky offspring — male and female! If you are considering purchasing a milking buck as a herd sire, breeding soundness examinations are recommended.
What does science say?
Gynecomastia is defined as the enlargement of male breast tissue. It can be benign, such as that reported with strong milking lines, or symptomatic of larger syndromes, such as hormonal and endocrine imbalances. Some males have no libido and show areas of calcification in the testes. (1) In other studies, the bucks had evidence of sex chromosome abnormalities resulting in infertility. (2,3)
Nubians are not the only breed that develops gynecomastia. There are documented cases in Saanens, Alpines, and LaManchas, though it could be found in any dairy breed. While no formal genetic studies are available in goats, many believe it is a direct result of genetic selection for high production. It does follow lines. Eliminating the trait in bucks would have the same result in does, as the evidence demonstrates that it does not follow gender.
As long as we continue to select for these traits, bucks with udders will become less of an oddity. Selection has consequences. Welcome to the new normal.
Studies related to gynecomastia in goats:
- Lambacher, Bianca & Melcher, Y. & Podstatzky, Leopold & Wittek, Thomas. (2013). Gynaecomastia in a billy goat – A case report. Wiener tierärztliche Monatsschrift. 100. 321-325.
- Panchadevi S.M., Pandit R.V. Milking males—two case studies. Indian Vet J. 1979;56:590-592.
- Rieck G.W., et al. Gynakomastie bei einem Ziegenbock. II. Zytogeneticsche Befunde: XO/XY. Mosaik mit variablen Deletionen des Y-Chromosoms. Zuchthyg. 1975;10:159-168.
- Wooldridge A., et al. Gynecomastic and mammary gland adenocarcinoma in a Nubian buck. Can Vet J. 1999;40:663-665.
Originally published in the May/June 2021 issue of Goat Journal and regularly vetted for accuracy.