What are the methods for selective breeding of superior varieties in gecko farming?
Once breeding stock is available, an excellent breeding population should be gradually established, so adult geckos and eggs should be further selected, with superior individuals forming the population, continuously increasing the body weight and egg production of breeding geckos, thereby improving the economic benefits of gecko farming.
1. Selection standards Generally, adult geckos have a body length from snout to cloacal opening of 12-16 cm, a tail length of 10-14.5 cm, and a body weight of 60-80 g, with the heaviest reaching over 100 g. Breeding geckos kept for selection should have a body length above 15 cm and a body weight above 70 g; those failing to meet these standards should be kept in a separate group and treated as commercial stock. In terms of reproduction, a female adult gecko generally lays 2 eggs per year, but under artificial rearing conditions, due to adequate feed and rich nutrition, some individuals can lay eggs twice a year, with 2-4 eggs each time. Based on this, among individuals meeting the body weight and body length standards, select those that lay eggs twice a year or lay more than 2 eggs at a time. Through generation after generation of selective breeding, a superior population with large body size and strong reproductive capacity can be developed in 5-8 years.
2. Selection methods
1) Adult selection
2) Egg selection Generally, large female geckos lay large eggs, and female geckos in good physical condition also lay large eggs, so eggs for breeding should be those above 6.5 g, incubated separately. Young geckos hatched from large eggs are also large and can be raised as breeding geckos. Young geckos hatched from eggs below 6.4 g can be raised as commercial geckos.
3) Selection of young geckos The natural incubation period of gecko eggs in the same year averages 105 days; under artificial incubation conditions, the incubation period is about 70 days. Select eggs above 6.5 g; under artificial incubation conditions, young geckos that hatch within 70 days and have a hatch weight above 4.5 g can be raised as breeding geckos, while those with an incubation period exceeding 70 days or a hatch weight below 4.5 g should be placed in the commercial group for rearing. This is because individuals that hatch early are robust, and those with a heavy hatch weight grow fast and are large.
Through the above three selection methods, generally after three generations, the quality of gecko breeding stock can be greatly improved.
3. Female-to-male ratio and breeding egg selection The ratio of adult females to males should be appropriate, so that the egg fertilization rate is high. Experiments show that with a female-to-male ratio of (3-5):1 under free mating, the egg fertilization rate is relatively high, so under artificial rearing conditions, the female-to-male ratio of breeding geckos is best at 5:1. Before incubation, gecko eggs should be selected. Normally developing eggs are white when just laid, and after about 20 days turn pale flesh-colored or flesh-colored; if opened at this time, a large number of white threads can be seen distributed in a network on the yolk. After about 1 month they turn lead-gray, and after about 2 months the eggs turn pale gray-black, until after 3 months the young break out of the shell, at which time the eggshell is blood-red. During embryonic development, the eggs feel heavy when held in the hand, and no matter when they are weighed, the weight loss does not exceed 1/5; such eggs are normal eggs. If the weight loss rate exceeds 1/5, it is very likely a dead embryo. Geckos sometimes also lay soft-shelled eggs; because bacteria can easily enter soft-shelled eggs and their surface is prone to mold, they cannot be put into incubation. Unfertilized eggs have white shells, and there are also some especially small eggs, which are deformed eggs and cannot be incubated.