Introduction
Artificial insemination (AI) has been the most powerful tool for livestock improvement ever available to the breeder; however, this technique has not been well developed as a routine method for breeding camelids compared with its fast and universal application in other farm animals. This review will summarize our current understanding of semen characters and AI in the Bactrian camel [1-6].
Semen Collection
During the breeding season all anticipated semen donors for AI programs are examined to ensure they are in good condition. Sexual behavior such as libido and the number of females each male mounts is recorded daily, as well as their acceptance of different kinds of artificial vaginas (AV) and dummies. Some incidental irregularities of semen characteristics may be explained by deviations from normal mating behavior of a donor bull. Only males with excellent reproductive performance that produce high quality semen and have good production potential should be selected for AI. Attempts to collect semen can then be carried out on alternate days, or if necessary daily, but with at least one rest day each week. Semen can be collected reasonably easily using an AV similar to that used for bulls with an inner rubber lining.
The male Bactrian camel is not very sensitive to temperature, pressure and lubrication inside the AV, but since copulation can be a lengthy process, taking anything from 3 - 25 minutes, and since the temperature during the winter rutting-season in China is low (as low as -20oC), the temperature inside the AV should be 40 - 41oC. The water-jacketed semen collection flask should also be kept warm at 37oC to avoid cold shock for the sperm. When collecting semen, the male should tease a receptive female in order to establish olfactory contact. The female is then restrained in a recumbent position, so that she cannot stand up when mounted, and the male is lead up from behind. When the male sits down on the female and makes a few thrusts, the operator grasps the male's sheath and directs his penis into the AV. and holds it there by manual pressure at the base of scrotum (Fig. 1). The male will make several thrusts, interspersed by periods of rest, until ejaculation is completed and the whole process of semen collection, from intromission of the penis into the AV to the completion of ejaculation, can take an average of 4.95 + 1.32 minutes although it may occasionally take a lot longer (20 - 25 min).