Lighting facility with radiation in UV- and visible spectral ranges for poultry
The main technical requirements specified for irradiation lighting facility (ILF) and parameters used in calculations are determined by the intended purpose of facility. Further, it is necessary to take into account the following:
• Characteristics of detector of optical radiation (spectral and integrated sensitivity of detector, time dependence of detector response on radiation);
• Requirements to productivity (quantitative and qualitative characteristics of finished product per unit of power);
• Operational conditions (climatic conditions, environmental characteristics);
• Requirements to technical and economical characteristics (amount of capital expenditures, operational costs, payback period).
In accordance with the specification, ILF is intended for the irradiation of poultry. The main characteristics of radiation detector included the spectral sensitivity of poultry skin and vision organs. ILF was developed on the basis of radiation sources in UV and visible spectral ranges (Fig. 1).
The facility (irradiator) contains: frame 1, reflector 2, four loops 3 for irradiator suspension. The top part of irradiator 2 consists of rectangular opening 4. The lower base of frame 1 has flanged edge 5. Around the perimeter of output of the frame 1 the reflectors 6, light windows of which are oriented downwards, are secured on flanged edge 5. Two erythemal lamps 7 are installed in the focal plane of every reflector 6. Two bactericidal lamps 8 are placed on the top base of frame 1 in intracavity. For the purpose of connection to supply network every couple of lamps (7, 8) is equipped with the standard electric fixtures and chokes (drivers) 9 fastened on metal section 10. The module 11 is installed on metal section 10 with blue and green light emitting diodes 12 located on it and equipped with electric fixtures and drivers 9. Developed facility and principle of its operation are described in details in the paper .
The prototype of facility was made, and the measurements of its basic parameters were performed. Measurements of curves of radiation intensity from the lamps of all groups and light emitting diodes were performed on photometer bench using the detectors of UV and visible radiation by standard methods.
The sources of ultraviolet radiation of the area C (UVC) of DBM-15 type were used in the irradiator in capacity of bactericidal lamps; the sources of ultraviolet radiation of the areas B and C (UVB, UVC) of LEB-15 type were used in the capacity of erythemal lamps. The lamps of LEB-15 with higher efficiency differed from the standard lamps of LE-15 type by the presence of certain portion of UVC radiation, except for UVB radiation, with the ratio of energy flow FUVC : FUVB = 1 :4.2 [2, 3].
In order to carry out the tests in the premises for poultry breeding, the calculations of irradiance were performed using the special developed program with algorithms for simultaneous use of optical radiation sources of four types .
Calculations were based on the determination of spectral irradiances brought to the same measurement units, at the points of operating surface separately for every closely-spaced source. Formula for the calculations of spectral irradiance from the ith irradiation device (ID) at the points of operating surface has the following form:
where Fi(λ) – spectral radiation flux from ith source, W; η, К3 – coefficients of use and reserve; h – height of suspension above the operational surface, m; аi – distance from ID to reference point in projection to horizontal plane, m.
Spectrums from every source were summed up by wavelengths; the integral values of irradiance were determined.
Algorithm implementation was performed in Delphi medium. In the window 1 the calculation of total irradiance at any point of operational surface is performed with the indication of its coordinates by mouse click after the arrow cursor is set on it (Fig. 2a). In the window 2 of the program the spectral distribution of irradiance is displayed in W/m 2 due to the action of four radiation sources (Fig. 2b).
Calculation of ILF with experimental irradiators for the purpose of radiation in the areas UVB and UVC was performed using the program [5, 6]. As a result of calculation, it was established that at the suspension height of 1.8 m the average irradiance of UVB area at the level of backs of illuminated birds was 24.20 mer/m 2 (maximum – 52.4 mer/m 2); average irradiance of UVC area at the level of backs of illuminated birds was 12.34 mW/m 2 (maximum – 23.1 mW/m 2). It order to convert the efficient erythemal irradiance from mer/m 2 into mW/m 2 for the lamps of LE 15, LEB 15 type in accordance with the spectrum of erythemal efficiency given in GOST MEK 60335-2-27-2009 it is required to use the factor 1.25.
The radiation spectrum obtained with the help of developed facility and facility with illumination luminescent lamps of LB 40 type corresponded to the spectral erythemal efficiency and spectral sensitivity of poultry vision organs, and it is the necessary condition for the enhancement of efficiency of lighting facilities .
When evaluating the efficiency of developed ILF under industrial conditions, the following parameters were studied: body weight gain, safety of livestock, egg yield per laying bird, and the calculation of economic efficiency was performed. The uniformity of stock is one of the major parameters of productivity; it is characterized by the stock uniformity by body weight. Uniformity is one of the most efficient technological methods of improvement of poultry productivity; it allows regulating the physiological development of birds at early age in accordance with developed standards, which are significantly lower than the genetic potential of birds; it allows estimating the reproductive functions of cockerels and egg production of laying hens and influences on the safety of birds. Uniformity can be calculated using the variation coefficient, which is determined on the basis of division of standard deviation in body weight by average body weight.
In order to estimate the influence of spectral structure of ILF with ultraviolet lamps and blue-green light emitting diode cluster on young birds, the experiment was carried out under industrial conditions. In every test using the analog method, 2 groups were formed (control (basic) and experimental groups) from day old replacement pullets and cockerels of commercial stock of Ross 308 cross. Microclimate conditions of poultry house were optimal. 2–3 days prior to the arrival of day old chicks into poultry house the premises were heated up, the floor temperature was maintained at the level not lower than the temperature in premises in order to avoid the supercooling of chicks. Temperature control was performed by registration of thermometers. Good mobility, active feed eating were observed in young birds; the stock distributed evenly around the area of premises; the bird noise was absent, and all these facts prove the normal temperature of poultry house. During the first 2–3 weeks the humidity was maintained at the level of 70%, on the fourth week it was 60%. The level of relative humidity was regulated with the help of heating system and ventilation. In poultry house for the purpose of supply of required quantity of fresh air and in order to decrease the level of respiratory diseases, the ventilation was used. Conditions for maintenance of birds from control and experimental groups were identical and provided in accordance with the guidance . Birds were grown in close-type poultry house for the optimal control of puberty. In darkness the illumination intensity did not exceed 0.5 lux. In control (basic) variant the luminescent lamps of LB 40 type were used for general illumination, and in experimental variant developed facility with ultraviolet lamps and blue-green clusters was used in addition to luminescent lighting. For experimental groups, at the expense of use of local illumination the value of illuminating intensity was by 7 lux higher at the average. Selection of illumination conditions was also based on recommendations of the firm – producer of poultry. Irradiation conditions: erythemal lamps were turned on once a day at 8:30 am for 15 minutes until 14-days age; two times a day at 8:30 am and 1:00 pm for 15 minutes starting from the age of 14 days; bactericidal lamps were turned on 2 times a day at 8:30 am and 1:00 pm for 1.5 hours until 14-days age, and starting from the age of 14 days the period of one irradiation was increased from 1.5 to 2 hours. Upon local illumination by light emitting diodes the following conditions were used: 1st day – 24 hours; 2nd day – 23 hours; 4th–10th day – 20 hours; 11th day and further – 8 hours.
The following parameters were taken into account and determined in studies: input parameters – irradiation dose and time, output parameters – uniformity of stock, safety of stock, egg production per average laying bird, yield of eggs, body weight of birds.
In order to obtain the specified parameters in future, the bird weight during the early development period should be not lower and even higher than the target value of weight. During this period the formation of skeleton, which afterwards remains practically for the whole period of life, takes place, and the basis of future stock productivity is generated. Stress, which can occur due to a number of factors such as cannibalism (picking of each other by birds), confinement of large groups, has the negative influence on poultry weight. Productive potential of poultry in general is formed during growing and therefore this period is extremely important but the curve of body weight increase preceding this moment and bird conditions at this age also play significant role. The task of growing consists in allowing the birds to develop in accurate accordance with the plan and it grants the opportunity to control hormonal functions. In turn, hormonal functions are determined not only on the basis of body weight at the end of growing but on the basis of dynamics of body weight increase, to a greater degree. Therefore, one of the tasks consisted in the obtainment of the weight, which is higher than the target weight, during the first weeks of life.
The birds were weighed once every week, and the stock uniformity was determined in analogous manner for both groups. Target weight and curve of body weight increase were developed together with the employees of poultry farm.
Experiment 1. Day old laying hens of replacement young stock of Ross 308 cross were the study object. Ross crosses are distinguished by fast growth, efficient feed consumption and excellent viability. Energy value of hen egg is quite high. 100 g of yolk of hen egg contain 1600 kJ of energy, 100 g of white – only 214 kJ.
During the first week the birds were fed in abundance because in case of large amount of feed the competition is practically absent, and birds have practically identical body weight increases.
In the experiment, as opposed to control, the curve of growth was smooth as much as possible, the abrupt and rapid variations of body weight were avoided. When laying hens reached the age of 105 days they were transferred to another section, and experiment was continued up until the age of 210 days. The level of egg production of birds was determined on the basis of quantity and quality of eggs laid during the first productive period. Evaluation of laying ability per average laying bird (in foreign literature, productivity index) was performed on the basis of ratio of number of the eggs laid by the stock during reference period to the average stock of laying birds for the same period. Results of uniformity, safety, egg laying ability per initial and average laying bird, egg yield for both groups are specified in Table 1 .
Having performed the comparative analysis, the conclusion can be drawn that developed method of illumination and irradiation allows enhancing the uniformity of commercial stock from replacement young stock by 9% and bird safety by 4%. Experimental group also had good appetite; there was no picking. Both groups had correct feathering.
The conclusion can be drawn that the illumination in accordance with suggested scheme has positive influence on productive and physiological qualities of replacement young laying hens. Negative effects of insufficient weight were avoided in both groups because in both groups the weight has reached the target value, however, in control group the weight was higher than target weight and it caused higher percentage of double-yolk eggs, higher need in feed, reduction of total number of eggs.
Experiment 2. Day old cockerels from replacement young stock of Ross 308 cross were the study object. The special attention was paid to the control of body weight of cocks because they are inclined to fast weight gain. Physiological and reproductive qualities of cockerels depend on weight. Experiment results showed that for the whole period of growing 100% safety of young stock was observed only in experimental group; during all age periods the body weight of birds in experimental group reached the target value as opposed to the experimental group and it has significant value for the cockerels from parent stock. The study results are given in Table 2.
The annual average economic effect per 300 animals is 722 700 rubles. Calculations demonstrate that stock safety and uniformity allowed reducing the cost of production .
Thus, upon the use of the system of general illumination with standard luminescent lamps and local illumination and irradiation from blue-green light emitting diode clusters and ultraviolet lamps in developed lighting facility, the improvement of light and color environment in poultry house is provided, and this fact enhances the poultry productivity parameters and economical efficiency of use of lighting facilities.