European jackal
The European jackal is the largest of the golden jackals, with animals of both sexes measuring 120–125 cm (47–49 in) in total length and 10–13 kg (20–29 lb) in body weight. One adult male in North-Eastern Italy is recorded to have reached 14.9 kg (33 lb). The fur is coarse, and is generally brightly coloured with blackish tones on the back. The thighs, upper legs, ears and forehead are bright reddish chestnut. Jackals in Northern Dalmatia have broader than average skulls, which is thought to result from human induced isolation from other populations, thus resulting in a new morphotype.
Testicle
In seasonal breeders, the weight of the testes often increases during the breeding season. The testicles of a dromedary camel are long, deep and in width. The right testicle is often smaller than the left. The testicles of a male red fox attain their greatest weight in December–February. Spermatogenesis in male golden jackals occurs 10–12 days before the females enter estrus and, during this time, males' testicles triple in weight.