Effects of Tetracycline on Sperm and Fertility - Page 1

My Stud was just put on 21 days of Tetracycline for a bacterial infection. I was planning on breeding my bitch this cycle which is due to start in 2 weeks. Does anyone have an information that says the antibotics will effect his sperm? Thanks.

http://www.drugs.com/pro/tetracycline.html

ANIMAL PHARMACOLOGY AND ANIMAL TOXICOLOGY

Hyperpigmentation of the thyroid has been produced by members of the Tetracycline class in the following species: in rats by oxyTetracycline, doxycycline, minocycline, Tetracycline PO4 and methacycline; in minipigs by doxycycline, minocycline, Tetracycline PO4 and methacycline; in dogs by doxycycline and minocycline; in monkeys by minocycline.

Minocycline, Tetracycline PO4, methacycline, doxycycline, Tetracycline base, oxyTetracycline HCI and Tetracycline HCI were goitrogenic in rats fed a low iodine diet. This goitrogenic effect was accomplished by high radioactive iodine uptake. Administration of minocycline also produced a large goiter with high radioiodine uptake in rats fed a relatively high iodine diet.

Treatment of various animal species with this class of drugs has also resulted in the induction of thyroid hyperplasia in the following: in rats and dogs (minocycline), in chickens (chlorTetracycline) and in rats and mice (oxyTetracycline). Adrenal gland hyperplasia has been observed in goats and rats treated with oxyTetracycline.

TEVA PHARMACEUTICALS USA

http://www.drugs.com/pro/tetracycline.html

What is or are the bacteria?..try Ciprofloxacin,usually in a couple of days ,sperm is back,but still need to do full cycle...it all depends in the bacteria he has..good luck

According the Plumb's Veterinary Drug Handbook, the only reproductive warning is in regard to pregnant females--because it can retard fetal skeletal development as well as cause discoloration to deciduous teeth, tetracycline should only be given during the last half of the pregnancy, and only if the benefits and necessity of treatment outweighs the risks.  That said, the tetracyclines do travel fairly thoroughly throughout the body, including the prostate, and it has been documented that tetracycline can be toxic to mature sperm when there's direct contact.  From the book, Drug-Induced Infertility and Sexual Dysfunction, by  By Robert Forman, Robert G. Forman, Susanna K. Gilmour-White, Nathalie H. Forman:

"Tetracyclines do not appear to affect spermatogenesis, but some forms may have a direct toxic effect on mature sperm. Chlortetracycline has deleterous effects on human sperm at concentrations of 100mg/l and minocycline has been found to be toxic to bull sperm."

The text does go on to caution that the few published studies that identified sperm toxicity from tetracyclines were done prior to 1975, and no evidence of tetracycline-induced toxic effects on sperm has been demonstrated in studies done in more recent years. 

From the International Programme on Chemical Safety's website  http://www.inchem.org/documents/jecfa/jecmono/v36je06.htm :

" Groups of male dogs (4 mongrel dogs and 4 beagle dogs) were fed diets containing 0.1, 0.3 or 1% TC hydrochloride for 24 months (equivalent to 25, 75 or 250 mg/kg bw/day, respectively). An interimsacrifice of 1 beagle and 1 mongrel dog of each group was performed at 12 months for microscopic examination. No effects were observed onclinical signs, mortality, body weight, food consumption, haematology ALP, bromosulfophtalein clearance, urea nitrogen determinations,testes and epididymides weight, macroscopy, concentration and motility of the spermatozoa, or appearance of semen. The bony structures of all dosed dogs showed a yellowish coloration. The intensity of the colour was related to the dose fed. A brownish-black pigmentation with a dose-related intensity was observed in the thyroid glands of the dogs of all groups. Microscopic examination of the thyroids revealed intracytoplasmic granules in the follicular epithelial cells of most of the treated dogs. This effect might be caused by deposits of TC or its metabolites. Histopathological changes were not observed (Deichmann et al., 1964).


All that said, any reported toxicity to sperm appears to be correlated to dosage and length of treatment.  As he's just been started on the drug, within the next two weeks I'd expect the concentration of tetracycline in the prostate to be of potential concern...so you might want to consider lining up another stud that's acceptable AND easily accessible to you, and have your dog's sperm quality checked in about 14 days to see if it's viable and confirm the sperm are normal.  That way, if things don't look good for using your dog in this upcoming cycle in your bitch, you won't be trying to figure out who you can use at the last minute should you still want to breed her on this heat.