Fertile goose eggs can be produced by artificial insemination and, if done properly, the level of fertility can be as high or higher than those obtained with natural mating. However, this technique is not usually used for the commercial production of goslings for the following reasons:
the high labour requirement: both semen collection and insemination require two people;
the semen production of ganders varies: on average, a Landes gander gives 0.3ml and 150 million spermatozoa per ejaculate but ganders vary as do different ejaculates from the same gander;
the geese must be inseminated twice a week to maintain an acceptable level of fertility.
However, in cases such as pedigree matings or when there is a shortage of ganders during a breeding season, artificial insemination can be useful.
The technique of artificial insemination begins with the collection of the semen. To maximise the percentage of ganders producing semen and the volume of semen produced, ganders should be housed individually. Pens of approximately 2 m2 have been shown to be satisfactory. To obtain clean semen, the ganders should have their feed removed 12 hours before the semen is to be collected.
Ganders should also be practised once or twice a few days before starting semen collection. The person collecting the semen sits on a stool and holds the gander on his lap as shown in Figure 24. He or she stimulates the gander by stroking his back from the middle towards the tail, while at the same time stroking the abdomen towards the vent with the other hand. After doing this several times, the thumb and the index finger of the right hand massage the pubic bones lightly. This causes the gander to extrude the phallus and, if the bird is producing semen, results in ejaculation. A second person is required to collect the semen with a suitable receptacle. The semen is released at the base of the phallus but it may run along the canal which extends the length of the phallus and be collected anywhere along its length, either through aspiration from the canal, or by collection in a centrifuge tube or other suitable receptacle.
FIGURE 24. Procedure for collecting semen from a gander
(Source: Johnson, 1954)
It should be noted that males in their second or subsequent breeding season are more likely to produce semen than young males in the first breeding season.
When preparing to inseminate the female, it must be noted that the oviduct does not become exposed as it does in the chicken and turkey. To inseminate the female, one person holds the bird by both legs in a horizontal position with its head toward him and under his right arm. The second person inserts the index finger of his left hand into the vent and, by palpation, locates the opening of the oviduct. The syringe, with or without an attachment, containing the semen is inserted into the vent and then into the oviduct by using the finger as a guide, and the semen is deposited.
Geese should be inseminated twice a week with 20 million spermatozoa per insemination. Ganders exhibit a lot of variation in both ejaculate volume and the number of spermatozoa per ejaculate. Average figures however would be a volume of 0.3 ml of semen and a total of 150 million spermatozoa per ejaculate. Therefore a rule of thumb would be to use 0.05 ml of pooled, undiluted semen per insemination (5-10 ganders). However, if equipment is available, it is recommended that the concentration of spermatozoa be determined for each pooled semen sample before insemination. Semen can be collected from ganders 2-3 times per week.
There are no specific diluents for gander semen but it can be readily diluted with a number of poultry semen diluents without any deleterious effect on fertility. One is the Beltsville Poultry Semen Extender as described by Sexton in his 1977 publication. In addition, if required, gander semen can be held up to six hours at 4°C if diluted in a standard poultry semen diluent. Some research has been carried out on freezing gander semen, but the results are not yet good enough to make use of this technique.