— How to choose the right drugs to reduce microbial contamination of premises?
— First of all, we must take into account the direction of the production cycle of a given premises. A lot depends on whether this premises is a livestock breeding, poultry farming, or a premises where poultry is slaughtered, where poultry is butchered, or where cooling occurs, or something else, or whether it is a hatchery, everything - this will influence the choice of drug.
If there are animals in the room, and we carry out disinfection in the presence of animals, then, accordingly, we must select such drugs and the concentration of drugs that will be safe for them.
If a livestock building is being prepared, in which the initial disinfection was carried out, the so-called “mud” - when everything is processed before washing and cleaning, and then, when the surface is clean and dry, treatment is carried out either with the same disinfectant or with a different disinfectant, but here The manufacturability of the drug itself plays a role, namely which drug will be most acceptable in the technological cycle of the room. There are also detergents and disinfectants that can be used.
It is necessary to take into account the harmlessness factor, that is, harmlessness in relation to people and actually harmlessness in relation to livestock facilities and harmlessness in relation to equipment. The drug must have the quality of neutrality to surfaces - the equipment must be protected. We cannot use corrosive products where we have metal equipment because it will not last long, or we must use concentrations that will not be corrosive to the equipment. As for harmlessness to people, the position is clear: everything is processed by people and we must take care of our staff and use disinfectants that are harmless to people.
A significant nuance is the manufacturability and versatility of application methods. Manufacturability is the ability to use it using any sprayers or applying it to surfaces using technological devices. The versatility of the methods of application is the ability to either soak some equipment in it, or simply wash it with a rag, apply it with irrigation, or use it as an aerosol.
When choosing a disinfectant, we must take into account the degree of microbial contamination; it may also depend on the season of the year. The degree of its activity in relation to a wide range of pathogenic microflora - here I also mean fungi, viruses, and microorganisms, that is, in relation to all microflora, because there are quite resistant microorganisms, for example, Pseudomonas or Aspergillus, they are very resistant to external environment, and not all disinfectants act equally well on them. Despite the fact that the drug may say that it affects a given microflora, unfortunately, in industrial conditions everything is not always so simple.
If there is a certain contaminant that is typical for your enterprise, then it is for this that you need to select a drug that will work effectively. To do this, you can isolate it and determine its sensitivity to the disinfectants intended for use.
The issue of price cannot be ignored . The important thing here is that you don’t always need to look at the cost of a liter or kilogram of disinfectant. The choice is still determined by the cost of treating a square meter of room - how much this disinfectant will cost already in diluted form, in the required concentration to treat a square meter of room. This is how the costs of the drug are calculated.
— How does the quality of all disinfection treatment affect the prognosis of infectious pathologies?
— It has a direct effect, because if disinfection is carried out with insufficient quality, then we can assume that practically no disinfection was carried out, and the microflora remains. Moreover, it is the pathogenic microflora that tends to remain to a greater extent. Although we usually do tests on intestinal microflora - we take swabs for E.Coli and evaluate the quality of surface treatment after disinfection. Here you also need to understand that there must also be a preliminary forecast - that is, the accumulated history of the enterprise: what contaminants are present, that is, is Salmonella present, for example, or is there Pasteurella, Pseudomonas aeruginosa, coccal microflora, aspergillus.
All this will influence the further forecast and the development of measures to prepare the premises, which will include not only washing and disinfection of the premises, but also the so-called “clean period” - a certain time that must pass after the final disinfection before the birds are boarded, that is, called biological rest of the room.
This is a very important process that is often not followed in enterprises, resulting in less effective disinfection efforts . Even if a very high-quality disinfectant is used in the required dosage, but due to the fact that you have not done biological rest of the room, some part of the microflora in this room will still not have time to die. Thus, when the room is opened, ventilated, and a day-old chick is placed, the chick will be contaminated with either viral, fungal, or bacterial microflora. Accordingly, the farm owner will receive as a result a decrease in productive qualities and an increase in waste - that is, a negative forecast for the epizootic situation.
And this situation is very common; they often talk about broiler farms, because they tend to reduce preparation time due to the fact that they want to get more MEAT per square meter during the year. Accelerating the growth of a broiler is quite problematic if the farm has already reached high growth rates, and then either they violate such an indicator as stocking density, plant more birds, which in turn again worsens productivity, or what the producer does more often is reduction time frame for preparing the premises. Of course, this is very tempting for the owner, because it makes it possible to get more meat and increase profits, but in this way there is a very rapid accumulation of microflora in the room due to the fact that biological rest does not occur.
There is a transfer of microflora, including pathogenic ones, which, when traveling on the bird, increase their virulence and pathogenicity. Thus, at the beginning the indicators were excellent, there was no colibacillosis, but after 6-12 months colibacillosis appears, which did not exist. The question arises: what is the reason? It seems like disinfection is carried out efficiently, washes are taken and the results are good. But the fact is that the washes are taken immediately after disinfection, and if we take them after 2-3 days, then it is quite possible that there will already be growth there. This is due to the fact that the colony is protected from external influences, that is, on the surface of the colony from above it secretes biologically active substances that protect it from the effects of disinfectants and not all disinfectants are capable of destroying this biological film.
By the way, regarding the question of choosing a disinfectant, we must also take into account this point, because often, when we read the instructions for the drug, it says that in a certain concentration it can be used to treat such and such a surface. But the manufacturer does not always test the drug under all conditions: tests are carried out on a dry surface, a disinfectant is applied and, accordingly, it works, but if we are talking about a watering system, or a feeding system, especially in the risk zone, the feeding pipes in which the auger goes are inside A fairly large array of biological plaque is formed, such as microflora, algae, fatty films in the feeding pipes, because there is oil in the feed , and accordingly fatty oil films accumulate. A large number of microflora multiply in this nutrient medium, and already recommended concentrations of the drug may often not work as effectively with such contaminants. And we have to somehow approach it differently, that is, individually in each case, use several disinfectants, etc.
— If the qualitative microbial composition of the air environment and the design of poultry houses varies by season, will the means of disinfection change and will their dosage change?
- Yes, this may change depending on seasonality or depending on the risks of the arrival of some contaminants, that is, for example, if an egg comes from an infected bird, for example, with enterococci - and we assume that this will be bacterial contamination of the egg , then, Accordingly, it will be necessary to change disinfectants in order to minimize contamination of the hatchery with this egg.
When seasonal temperature fluctuations occur, some of the premises are not heated, for example, in an industrial laying hen, accordingly it will be necessary to select disinfectants depending on the temperature conditions in the room. Many disinfectants work at fairly high temperatures, above at least 16 degrees.
And there are practically no disinfectants that work at subzero temperatures. If you take formalin, then it works at temperatures above 20 degrees, and it is better that the temperature in the room is from 28 degrees. At low temperatures it will not work, that is, below 16 it generally loses its effectiveness very quickly, and if the temperature is close to zero, then accordingly the effectiveness of formalin will also tend to zero.
— How is the duration of a preventive break determined? Only according to the production schedule?
- There are 2 points here. On the one hand, we depend on production, on the other hand, we depend on the epizootic situation within the farm. Often, an epizootic situation, namely its deterioration, can dictate to us completely different cycles for preparing the premises, when we need, for example, the premises to stand for at least 10 days. The total preparation period is 14 days, of which 4 days are cleaning, washing, disinfection, and 10 days the room is clean, dry, disinfected, no one goes there, it is prepared for poultry landing.
Sometimes it even happens that during this period it is possible to do additional disinfection, for example, aerosol, in order to remove some kind of contaminant that cannot be removed by technological means - by introducing any drugs into the feed: antibiotics , coccidiostats, and so on. But often there are contaminants that cannot be treated with therapeutic methods, and the only method that can correct the situation is to increase the service gap, namely biological rest.
For example, with adenovirus infection, with reovirus infection, with malabsorption syndrome, and so on, we often cannot influence the bird in any way, because infection occurs very early, almost in the first days of life, and for this period there are still no means of influence, economically justified, so the only way is to increase the gap so that the pathogenic microflora is killed in a clean room.
Sometimes it happens that during an outbreak of an acute infectious pathology we have to make a big gap; for example, with bird flu, we have a 4-month sanitary gap. There is a technological cycle, and if we change something in it, then this is, as a rule, a forced measure, which is dictated by a change in the state of the poultry population.