In the summer silkworm breeding, many farmers will put the window of the silkworm house on the screen window, in and out of the door of the silkworm house there will also do some protective measures, on the one hand, to prevent mice, cats, etc. from entering the silkworm house to make trouble, on the other hand, to prevent silkworm maggots and flies, because once the silkworm maggot flies enter the silkworm house, it is easy to lay eggs on the silkworm body, and the larvae will parasitize in the silkworm body, so that the silkworm cannot grow normally, and some lesions occur. Sometimes we will find that silkworms normally spit silk as cocoons, but there will be a small hole, in fact, this is the work of fly maggots, silkworms are parasitic by fly maggots after 5 years of age, drilling out from the inside of silkworm pupae, resulting in the death of silkworm pupae, and finally forming maggot hole cocoons, thin skin cocoons and other abnormal situations, this silkworm cocoon utilization value is not large, and it will cause certain losses to farmers.
Fly maggot disease may appear in each silkworm stage, once there is no corresponding preventive measures, resulting in some silkworm body parasitism, then there will be a loss of 10%-15% of the silkworm in the season, like some silkworm areas in southern China, summer and autumn silkworm period often appear hot and humid weather, the probability of silkworm maggot disease is significantly improved. Usually, silkworm maggot flies will go through 4 stages, namely insect eggs, larvae, insect pupae and flies, silkworm maggot flies have a strong ability to reproduce offspring, the higher the temperature, the more offspring they reproduce, like the northeast and north China, which can breed 4-5 generations a year, and East China has 1-2 generations more than the northern region, and South China can reach more than 12 generations, basically a month can breed a generation. Under normal circumstances, a female fly can lay 400-500 eggs, when the female flies lay eggs on the silkworm body, each silkworm will only lay 1-2 eggs, and after laying, it will find other silkworm bodies, so once there are silkworm maggots in the silkworm house, the impact on the benefits of silkworm farming will be more obvious. So what situations will cause maggot disease in the process of silkworm rearing? Personally, I think there are four main aspects.
Under normal circumstances, the doors and windows of the silkworm house need to do some protective measures, such as according to the screen window or curtain, in the summer and autumn, due to mosquitoes, flies, etc., many farmers will do some protection, and in the spring silkworm or late autumn silkworm, because the temperature is not very high, many farmers ignore the protection of the silkworm door and window. Because the silkworm maggot fly adult insect is a flying insect, if the doors and windows of the silkworm house do not do some protective measures, then it is easy to enter the inside of the silkworm house, when the female fly lays eggs on the silkworm body, it is easy to cause fly maggot disease, no matter when the farmer needs to strengthen the management of the silkworm house in and out, ventilation also needs to have certain precautions, more taboo is to directly open the door and window, the outside flying insects can enter and exit the silkworm house at will, which will only induce some silkworm diseases.
According to the breeding mode in most areas, the silkworm sand needs to be replaced frequently in the process of raising silkworms, which can make the silkworm grow in a relatively comfortable environment, but in the actual operation process, some farmers treat the silkworm sand more casually, such as replacing the silkworm plaque, there is no arrangement for specific area operations, and the silkworm sand is stacked at will, which can easily lead to some new problems. Under normal circumstances, the silkworm sand contains the remaining mulberry leaves, mulberry leaf stems, silkworm dung, silkworm urine, etc., but sometimes there are some germs, insect eggs, etc. hidden inside, plus sometimes there are some sick silkworms, and it is easy to have secondary infections when the silkworm sand is piled up at will. Some farmers will pile silkworm sand outside the silkworm house, ready to be used for farm manure, but the silkworm sand will emit some special smell after being exposed to the sun and rain, which is easy to attract silkworm maggots and flies, and once the silkworm maggots are active around the silkworm house, it is easy to fly into the silkworm house if they are not careful.
Silkworms after 5 years of age, you have to observe whether the silkworm has signs of spitting silk as a cocoon, when most of the silkworms begin to spit silk, you have to place clusters, with clusters as an auxiliary, silkworm cocoons will be more smooth, and it is more convenient to pick cocoons in the later stage. However, before placing the cluster, it is necessary to disinfect the cluster, if the cluster is not disinfected or the disinfection is not thorough before use, there are some eggs on it, once used, it may make the silkworm body infected with germs, if the female fly lays eggs on the cluster, the larva is easy to burrow into the silkworm body, and then there is an abnormal cocoon or even no cocoon. Sometimes after the silkworm is parasitized by fly maggots, the body color of the silkworm will turn purple, which is easy to be mistaken for sepsis, which requires farmers to observe more, and if necessary, the place of the lesion can be dissected.
In the countryside when raising silkworms, some places will set up silkworm cocoon acquisition stations, so that it is convenient for farmers to trade cocoons, if there is a local silk reeling factory, usually let the farmers themselves to the silk reeling factory for trading, silkworm cocoon acquisition station looks nothing, but in fact such a place is more complicated, because good cocoons and some abnormal cocoons are concentrated there. In the process of raising silkworms, if there is no silkworm disease, then the quality of the cocoon is relatively good, but if there is a pus silkworm, zombie silkworm, etc. during the period, then the quality of the silkworm cocoon will have a greater change, such an environment will create conditions for the silkworm maggot flies, many silkworm maggots will breed offspring there, and once the eggs are attached to the bag of the silkworm cocoon of the farmer, the farmer will spread after bringing it back.
No matter when to raise silkworms, for farmers, it is certainly not expected to have some silkworm diseases, because once the silkworm disease appears, it is likely that the early payment will be difficult to see the return, like some more contagious silkworm diseases, such as silkworm pus, serious will make the silkworm in the season out of harvest, the blow to the farmers is relatively large. Fly maggot disease is not a contagious silkworm disease, but if the preventive measures are not in place, it will also affect the income of silkworm farming, and when there are more silkworm maggots, it is more normal to reduce production by more than 30%. Of course, fly maggot disease is not so difficult as imagined, only need farmers in the actual breeding process to pay more attention to details, but also can be avoided, if due to negligence caused by fly maggot disease, do not panic too much, timely take corresponding measures, can reduce losses. In the process of sericulture, farmers need to master the following 6 points, which can effectively prevent and control maggot disease.
1. The doors and windows of silkworm doors and windows need to be set up with screens, curtains, etc., and personnel need to be strictly controlled when entering and leaving the silkworm room
Silkworms are more clear, silkworm house is not what anyone can go in, even if it is their own family, they also need to follow the relevant procedures, if they enter and exit at will, then it is easy to bring some problems. Silkworm maggot flies can fly around, especially sensitive to the breath of silkworms, if there are silkworm maggots in the silkworm house, once the female flies lay eggs, then the growth of silkworms will be adversely affected. In order to avoid silkworm flies entering the silkworm house, it is necessary to add some protective measures to the doors and windows of the silkworm house, the window can be installed with screen windows, the selection of holes is relatively small, and when there is a hole found, it is necessary to repair it in time, and there is a door that is more frequent in and out, you can consider installing two layers of door curtains inside and outside, so that there is double protection when people enter and exit, and silkworm maggots are not so easy to enter the silkworm house.
2. The precocious silkworms with lesions need to be isolated and clustered separately
Under normal circumstances, after the 5-year-old silkworm is parasitized by insect eggs, there will be a certain precocious phenomenon, after the silkworm plaque is found, it is necessary to pick it out in time, raise it alone, and it is also necessary to operate separately when it is clustered in the later stage, and it can be smoothly cocooned, and the silkworm cocoon should be picked in time and dried the cocoon, so that the maggot can be avoided from the silkworm pupae, thus forming a maggot hole cocoon. Another thing to note is that for parasitic silkworms, those that fail to make cocoons smoothly should also be properly handled, not discarded at will, and cannot be placed in silkworm plaques all the time, and need to be picked out, soaked in formalin or lime water for 1-2 days, and then buried in a different place. Once a small range of diseased silkworms are found in the silkworm house, the farmer should also observe more and make corresponding treatment in time to avoid greater losses while isolating and feeding.
3. Feed clean mulberry leaves to avoid insect eggs on mulberry leaves
When raising silkworms, whether the mulberry leaves are clean or not, will determine whether the silkworms can grow normally, different silkworm ages need to be fed different mulberry leaves, to ensure that the good mulberry is full, only by making the silkworms full of food, the resistance can be relatively strong, and the quality and yield of the cocoons will be significantly improved. However, in the actual breeding process, due to various reasons, the farmers will be fed unclean mulberry leaves, so easy to induce some silkworm diseases, because the female flies have a strong ability to lay eggs, if there are insect eggs on the mulberry leaves, after feeding the silkworms, the larvae may burrow into the silkworm body, and then there is maggot disease. In order to prevent insect eggs on mulberry leaves, in addition to paying more attention to picking mulberry leaves, farmers must also do a good job in the management of the mulberry garden, and do not provide a place for insect eggs to live, so that silkworms can eat clean mulberry leaves.
4. Silkworm plaques, clusters, etc. need to be thoroughly disinfected before use
Silkworm plaques, cluster tools, etc. are the auxiliary tools needed in the process of raising silkworms, but also more direct contact with silkworms, silkworms from 1 to 5 years old, each stage of time experience is relatively short, resistance is relatively weak, if the middle is infected by germs, or some other abnormal conditions, it is easy to affect the normal growth of silkworms. Silkworm plaques, clusters of tools before use, need to be cleaned, dried, disinfected, etc., especially in the previous season when there are more silkworm diseases, more attention should be paid to hygiene and disinfection, silkworm plaques, clusters can not have obvious insect eggs, only after the silkworm maggot eggs are eliminated in advance, it is possible to avoid fly maggot disease in the later stage.
5. Silkworm sand should be properly handled in a timely manner and should not be stacked at will
When the silkworm house found that part of the silkworm body is parasitic by silkworm fly maggots, in addition to the timely treatment of the sick silkworm, we should also pay attention to the treatment of silkworm sand problems, for farmers in most areas, the silkworm breeding process is necessary to deal with silkworm sand in time, especially in the southern summer sweltering hot and humid weather, silkworm sand if not cleaned up in time, easy to breed bacteria, there are insect eggs inside, will soon develop into adult insects. Once there are silkworm maggots and flies in the silkworm house, there may be insect eggs in the silkworm sand, which requires farmers to clean up regularly and in time, and the replaced silkworm sand cannot be stacked outdoors at will, and cannot be used to feed poultry, of course, it cannot be directly sprinkled in the mulberry garden as farm manure, which needs to be fully fermented and then used.
6. Use silkworm flies for drug control
At present, for fly maggot disease, there are also special drugs for prevention and control, that is, the use of silkworm flies, there are two main ways to use, one is to spray the dilution of silkworm flies on the surface of the silkworm body, the other is sprayed on the mulberry leaves, and then feed the silkworms mulberry leaves. In practice, these two methods can be combined, if it is found that some silkworms are parasitized by fly maggots, they can be sprayed on the silkworm body first, and then the prepared dilution can be sprayed on the mulberry leaves, so that the comprehensive control effect will be better. It should be noted that the silkworm fly dilution needs to be used now, can not be left for the next time to use, the amount of use needs to follow the corresponding operating instructions, if the use of anti-zombie powder or bleaching powder, temporarily can not use the silkworm fly, otherwise it is easy to affect the control effect.
In short, according to years of experience in sericulture, fly maggot disease can be prevented through some measures, in time a small number of silkworm bodies are parasitized by fly maggots, you can also use some drugs for prevention and control, compared with silkworm pus, fly maggot disease has a better place, that is, it will not be widely transmitted. As long as farmers usually pay more attention to detailed management, pay more attention to observation, and cooperate with the above six prevention and control measures, the loss of fly maggot disease to silkworm farming can be minimized.