Научная статья на тему 'Productive qualities of broilers at different management systems and amount of floor space per bird'

Productive qualities of broilers at different management systems and amount of floor space per bird Текст научной статьи по специальности «Животноводство и молочное дело»

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Ключевые слова
BROILERS / PRODUCTIVE QUALITIES / AMOUNT OF FLOOR SPACE PER BIRD / POULTRY GROWING TECHNOLOGY

Аннотация научной статьи по животноводству и молочному делу, автор научной работы — Yaskova Е. V., Gaponova A. V., Buyarov V. S.

To define rational amount of floor space per bird and study productive qualities of broilers of cross «Ross-308» depending on the rate of floor space per bird at growing, in cage batteries and on litter the investigations at broilers enterprises of the Orel region were carried out. Broilers were grown in cages KP-8L from the day age and to slaughter (tests 1 and 2) and on litter using floor equipment set of firm «Big Dutchman» (Germany). The number of chickens in the test groups was 90-108 heads. The basic technological parameters of chicken keeping (lighting program, microclimate, feeding program, and mixed feed nutrition) were the same for all groups and corresponded to «Maintenance of «Ross» broilers growing (2009)». At doing research and economic tests the zootechnic factors of broilers growing according to common methods were defined. Statistical analysis of the obtained data was done using personal computer with «Microsoft Excel» (2003) and «Statistica» software. It was proved that according to productive and zootechnic factors complex that rational amount of floor space per bird for broilers of cross «Ross-308» at duration of 38 days fattening to obtain 2,2 2,3 kg live weight is 25 birds/m 2 at growing chickens in cages, or 394,0 sm 2/bird; 20 birds/m 2 at growing chickens on litter. Due to chicken intensive growing in the best test groups feed conversion (1,69-1,75 kg) and European Productivity Index (EPI) (335,73-346,65 units) have improved. Poultry population safety in the groups with optimal amount of floor space per bird was 98,0 98,1%. At selection of amount of floor space per bird of broilers first of all is necessary to consider the implied final poultry weight.

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Текст научной работы на тему «Productive qualities of broilers at different management systems and amount of floor space per bird»

UDC 636.5.033.083.3

PRODUCTIVE QUALITIES OF BROILERS AT DIFFERENT MANAGEMENT SYSTEMS AND AMOUNT OF FLOOR SPACE PER BIRD

Yaskova Е.V., Gaponova A.V., Post Graduate students Buyarov V.S., Doctor of Agricultural Sciences Orel State Agrarian University, Orel City, Russia E-mail: bvc5636@mail.ru

ABSTRACT

To define rational amount of floor space per bird and study productive qualities of broilers of cross «Ross-308» depending on the rate of floor space per bird at growing, in cage batteries and on litter the investigations at broilers enterprises of the Orel region were carried out. Broilers were grown in cages KP-8L from the day age and to slaughter (tests 1 and 2) and on litter using floor equipment set of firm «Big Dutchman» (Germany). The number of chickens in the test groups was 90-108 heads. The basic technological parameters of chicken keeping (lighting program, microclimate, feeding program, and mixed feed nutrition) were the same for all groups and corresponded to «Maintenance of «Ross» broilers growing (2009)». At doing research and economic tests the zootechnic factors of broilers growing according to common methods were defined. Statistical analysis of the obtained data was done using personal computer with «Microsoft Excel» (2003) and «Statistica» software. It was proved that according to productive and zootechnic factors complex that rational amount of floor space per bird for broilers of cross «Ross-308» at duration of 38 days fattening to obtain 2,2 - 2,3 kg live weight is 25 birds/m2 at growing chickens in cages, or 394,0 sm2/bird; 20 birds/m2 at growing chickens on litter. Due to chicken intensive growing in the best test groups feed conversion (1,69-1,75 kg) and European Productivity Index (EPI) (335,73-

346,65 units) have improved. Poultry population safety in the groups with optimal amount of floor space per bird was 98,0 - 98,1%. At selection of amount of floor space per bird of broilers first of all is necessary to consider the implied final poultry weight.

KEY WORDS

Broilers; Productive qualities; Amount of floor space per bird; Poultry growing technology.

At present practical success in broiler industry first of all depends on the degree of production technologies allowance to use the genetic potential of fast growth, and very often this level corresponds to less than 80%. In this connection continuous improvement of technology and development of new resource saving processing technology of growing of advanced broilers crosses acquire great importance. That is why the investigations directed to increase of usage of broilers genetic potential for the sake of development of new technological solutions with regard to the peculiarities of the developed crosses are rather important [1, 4, 5, 6, 9, 12, 18, 19].

The starting point is that the main task of organization of technological process of broilers growing is to obtain maximum commercial yield from poultry house area unit at minimum labor and facilities costs. Being engaged in broilers meat manufacturing every enterprise must optimize not only economic indicators but also technological factors selected according to biological characteristics of growing poultry. It is necessary to find the right combination of such indicators as growing period, final live weight, amount of floor space per bird and meat output from placement area unit and for broilers of definite cross [2, 7, 10, 11,

13, 17, 21, 22].

To a large extent the obtaining of high quality production depends on broilers amount of floor space per bird. Amount of floor space per bird i.e. the broilers number per area unit (or floor space size per 1 broiler), depends on live weight, gender and age of a bird, microclimate and also growing technology, year season. Optimal amount of floor space per bird at broilers fattening is defined by production output from floor space unit, quality of

carcass and meat, feed efficiency, safety of poultry population, live weight to the slaughter period, profit, obtained per one bird, per unit area of production facilities [3, 8, 16, 20].

Researches on determination of amount of floor space per bird influence on broilers efficiency were done in many countries, but in connection with considerable number of factors, that influence the rate of amount of floor space per bird and indicators that define it, one-valued result was not obtained. Thus, amount of floor space per bird is a factor that must be studied constantly. Conclusions and recommendations of different authors on this question do not always coincide.

According to Technological Design Standards of Agro Industrial Complex 1.10.05.00101 amount of floor space per bird at growing on litter (1-8 weeks) is accepted equal to 18 birds/m2, and for large broiler chickens (1 - 10 weeks) - 16 and 14 birds/m2 for female chicks and male chicks correspondingly. Standards of amount of floor space per bird at cage keeping are accepted according to passport data of cage batteries contractor, agreed upon with equipment customer. At the corresponding grounding standards of amount of floor space per bird can be improved by project assignment: in this case at the usage of the produced equipment other than intended it is recommended to use the following data: at broilers growing (1-7 weeks) without gender differentiation- 320 sm2/bird, separately by gender - 300 sm2/bird for female chicks and 350 sm2 for male chicks [14].

In the European Union system amount of floor space per bird of broilers is defined by the regulations of poultry wellbeing during the growing process and corresponds to 33 kg/m2; 39 kg/m2 - at stricter standards or 42 kg/m2 - much stricter standards observed at longer periods. Standards concerned general poultry wellbeing during growing process, contain the requirements for adequate amount of feed and water, observation of comfort conditions of management in poultry house [15].

Investigations were done to study the broilers productive qualities depending on amount of floor space per bird at growing in cage batteries and on litter.

MATERIALS AND RESEARCH METHODS

The work was done according to the plan of research in the frames of target program of department «Poultry development in the Russian Federation for 2010-2012», and also according to Plan of fundamental and prior applied investigations on scientific support of Agro Industrial Complex development of the Russian Federation for 2011-2015, forming the ground of the State assignment and Program of fundamental scientific research of state academies of science for 2008-2012 on problem 07 «Develop resource saving, environmentally friendly technologies of production and processing of poultry production and create new competitive breeds and crosses of agricultural poultry on the ground of improvement of their selection and genetic potential of productive and reproductive qualities». Researches were done at the poultry meat production plant JSC of Agro Industrial Complex «Orlovskaya Niva » and poultry plant LLC «Orlovskye zory».

Chickens-broilers of cross «Ross-308» were research objects. During the tests the broilers productive qualities depending on amount of floor space per bird at growing in cage batteries and on litter were investigated.

Poultry feeding was realized by full ration granular mixed feed with combination of all necessary nutrients according to standards and recommendations of All Russian Science and Research and Technological Institute of Poultry and present recommendations for this cross. Management conditions (except amount of floor space per bird) were equal for all groups and corresponded to «Guidance of «Ross» broilers growing (2009)». Lighting program at broilers growing is presented in Table 1.

At doing research and economic tests the following zootechnic factors: live weight - by individual weighting of broilers of each group at the age of 1 day, at the 21st day of life and at the end of growing; daily average of live weight gain - was calculated by common formula; safety of poultry population during the growing period - by means of accounting withdrawn poultry with definition of withdrawal reasons; feed conversion was calculated by the data of

records of feed and live weight use and consumption. European Productivity Index (EPI) was calculated by formula:

EPI = (M*S / F*T) * 100,

where M - average live weight (kg); S - safety (%); F - feed consumption per 1 kg of gain (kg); T - term of growing (days).

Table 1 - Lighting program at broilers growing

Age, days Lighting intensity, lx Daylight period, h Off period, h

0-7 30-40 23C:1T 24 - 1

8-28 5-10 20C:4T 24 - 4

29-35 5-10 23C:1T 24 - 1

36-38 30-40 24S

The statistical analysis of the obtained experimental data was done using PC and software «Microsoft Excel» (2003) and «Statistica».

Results and their Discussion

The first test was done as a reconnoitering test to find out the influence of amount of floor space per bird on the zootechnic factors of broilers growing in cages to 38 days age and obtaining live weight of 2,2-2,3 kg. In test 1 4 groups of broilers were formed. The 1st group was control group where standard amount of floor space per chicken according to passport data of cage batteries contractor KP-8 L (295,5 sm2/bird) was used.

As the result of the carried out researches the increase of broilers productive qualities at decrease of amount of floor space per bird in cages was observed. Thus, the broilers of the experimental group 3 at the age of 38 days obtained live weight of 2231,4±21,7 g, that is by 4,92% (P<0,01) higher in comparison with the control group. Also it is necessary to stress good results of chicken growing in group 2, their live weight was by 3,15% (P<0,005) higher, than in control. It is proved that the influence of amount of floor space per bird at broilers growing in cages starts to make its effects shown on the factors of their live weight since three week-old age (Table 2).

Table 2 - Broilers productive qualities at different amount of floor space per bird in cage batteries

KP-8L; growing term -38 days (Test 1)

Groups

control 1 experimental 2 experimental 3 experimental

Factors Amount of floor space per bird

34 birds./m2 30 birds./m 29 birds./iT|2 27 birds./m2

(295,5sm2/bird) (328,3 sm2/ bird) (347,6 sm2/ bird) (369,4 sm2/ bird)

Accepted for growing, heads 100 90 102 96

Average live weight, g at the age of, days: - - - -

1 days 42,3±0,10a 42,3±0,11a 42,4±0,09a 42,2±0,10a

21 831,6±14,3a 844,1±12,7a 852,8±15,1a 871,9±13,46a

38 2126,8±23,2a 2169,5±19,8a 2193,8±20,36a 2231,4±21,76

Average daily gain, g 54,9 56,0 56,6 57,6

Feed expenses per 1 kg of live weight gain, kg 1,75 1,74 1,74 1,72

Safety, % 96,0 96,7 97,1 97,9

European Productivity Index, units 307,03 317,29 322,17 334,23

Note: hereinafter similar letters stand for statistically unreliable difference between groups, and different letters stand for statistically reliable difference at P< 0,05-0,001. The order of comparison of the average live weight data between groups: the control group is sequentially compared with experimental groups 1,2,3; then experimental group 1 is compared with groups 2 and 3; experimental group 2 - with group 3. Broilers amount of floor space per

bird (sm2/bird) is calculated based on cage floor area taking into consideration the number of chickens in cage being rounded to integral value).

The higher safety of broilers was in groups 2 and 3. The decrease of amount of floor space per bird of chickens from 34 birds/m2 (295,5 sm2/bird) to 27,0 birds /m2 (369 sm2/bird) was accompanied with some decrease of feed expenses per 1 kg of live weight gain. Maximum index productivity was obtained at growing broilers in experimental group 3 -334,23 units, it is by 27,2 units higher, than in control.

The second test was done for the repeated study of broilers productive qualities depending on amount of floor space per bird at growing chickens in cage batteries KP-8 L to 38-days age and obtaining their live weight 2,2-2,3 kg. In test 2 eight groups were formed: one control group and seven experimental groups (Table 3).

Table 3 - Productive qualities of broilers at different amount of floor space per bird in cage batteries

KP-8L; growing term -38 days (Test 2)

Groups

control 1 2 3 4 5 6 7

Amount of floor space per bird

Factors (D m j!2 E 32 heads/m2 (311,1 sm2/head) 30 heads/m2 (328,3 sm2/head) 29 heads/m2 (347,6 sm2/head) 27 heads/m2 (369,4 sm2/head) 25 heads/m2 (394,0 sm2/head) m2 d) a42 hs 22 heads/m2 (454,6 sm2/head)

Accepted for growing, heads 100 95 108 102 96 105 98 104

Average live weight, at the age of, days.: - - - - - - - -

1 day 44,1± ±0,10a 44,2± ±0,1 0a 44,1± ±0,11a 44,0± ±0,12a 44,1± ±0,11a 44,1± ±0,13a 44,0± ±0,11a 44,1± ±0,1 0a

21 832,9± ±13,5a 841,5± ±12,6a 849,2± ±14,1a 856,3± ±14,5a 876,1± ±11,36a 892,7± ±12,96=1 895,2± ±14,16a 897,8± ±15,66a

38 2131,2± ±23,1a 2153,1 ± ±22,4a 2182,3± ±22,9a 2195,8± ±21,06a 2234,4± ±20,86a 2269,3± ±19,86a 2281,6± ±20,16a 2287,9± ±20,26a

Average daily gain, g 54,9 55,5 56,3 56,6 57,6 58,6 58,9 59,0

Feed expenses per 1 kg of live weight gain, kg 1,76 1,75 1,75 1,74 1,72 1,69 1,71 1,72

Safety, % 96,0 96,8 97,2 98 97,9 98,1 98,0 98,0

European Productivity Index, units 305,91 313,41 318,98 325,45 334,68 346,65 344,10 343,04

Note: hereinafter similar letters stand for statistically unreliable difference between groups, and different letters stand for statistically reliable difference at P< 0,05-0,001. The order of comparison of the average live weight data between groups: the control group is sequentially compared with experimental groups 1 - 7; then experimental group 1 is compared with groups 2-7; experimental group 2 - with groups 3 - 7; experimental group 3 - with groups 4-7; experimental group 4 - with groups 5-7; experimental group 5 - with groups 6-7; groups 6 and 7. Broilers amount of floor space per bird (sm2/bird) is calculated based on cage floor area taking into consideration the number of chickens in cage being rounded to integral value).

Taking into account the results of the first test broilers of the control group were grown at standard amount of floor space per chicken accepted according to passport data of cage batteries contractor KP-8 L (295,5 sm2/bird, or 34 birds/m2). This amount of floor space per bird was maximal in the second test. Broilers of experimental group 7 were grown at minimal amount of floor space per bird - 22 birds/m2 (454,6 sm2/bird). The rest broilers groups according to the rate of amount of floor space per bird occupied intermediate position.

It is proved that by the complex of factors the rational amount of floor space per bird for broilers at fattening duration 38 days is 25 birds/m2 (394,0 sm2/bird). It is proved by the

maximum rate of European Productivity Index of the chickens of experimental group 5 -

346,65 units, exceeding this generalizing production factor in other groups by 2,55-40,74 units.

The most important factor, largely determining productive efficiency of broilers meat, is feed expenditures per production unit. The definite regularities in changes of feed cost value per 1 kg of broilers live weight gain depending on amount of floor space per bird are detected in our investigations. It is our opinion that the influence of amount of floor space per bird on feed payment is explained by the fact that at the undervalued amount of floor space per bird poultry has more vacant space in a cage; its physical activity is increased. It results in increased feed consumption. With increase of amount of floor space per bird and bringing it to rational broilers are kept more compact. It decreases physical activity and feed consumption. Overcompacted amount of floor space per bird results in stress, poultry crowding at feeders, competition for space, hierarchy and social dominance escalate. This results in decrease of feed consumption by broilers, its conversion worsening and at last in productivity decrease.

The third test was done for finding out the influence of amount of floor space per bird on zootechnic factors of broilers growing on litter to 38-days age and obtaining live weight 2,2-2,3 kg. Broilers were grown of using equipment set of firm «Big Dutchman» (Germany). 7 groups of broilers were formed. The 4th group was control, where standard amount of floor space per bird of chickens according to Technological Design Standards of Agro Industrial Complex 1.10.05.001-01 - 19 birds/m2 was used. Groups differed in head number, being placed on 1 m2 floor space of experimental section of poultry house.

As the result of the researches it was proved that according to zootechnic factors complex the optimal amount of floor space per bird at chicken growing duration of 38 days is 20 birds/m2 (group 5). The broilers of this group at 38 days obtain live weight 2278,2± ±20,8 g at safety 98%, feed expenses per production unit 1,75 kg. Productivity index in group 5 was maximum - 335,73 units (Table 4).

Poultry of different crosses reacts differently to compact placing. It defines the necessity of differentiated approach, i.e. amount of floor space per bird and growing term must be defined depending on the method of poultry cross growing.

Table 4 - Results of floor growing of broilers at different amount of floor space per bird;

growing term -38 days (Test 3)

Groups

1 2 3 4 (control) 5 6 7

Factors 16 heads/m2 (625,0 sm2/head) 17 heads/m2 (588,2 sm2/head) 18 heads/m2 (555,6 sm2/head) 19 heads/m2 (526,3 sm2/head) 20 heads/m2 (500,0 sm2/head) 21 heads/m2 (476,2 sm2/head) 22 heads/m2 (454,5 sm2/head)

Accepted for growing, heads 100 100 100 100 100 100 100

Average live weight, at the age of, days - - - - - - -

1 day 42,2± ± 0,10a 42,3± ±0,09a 42,1± ±0,11a 42,2± ±0,1 0a 42,2± ±0,09a 42,1± ±0,11a 42,1± ±0,1 0a

21 851,9± ±13,4a 860,4± ±14,3a 868,9± ±13,8a 880,1± ±12,2a 888,3± ±11,96a 854,4± ±11,7a 849,7± ±12,3a

38 2193,0± ±24,2a 2212,1± ±22,0a 2234,7± ±23,7a 2260,6± ±21,963 ±2 -° So °6m 01 |+ 2192,9± ±22,5a6B 2177,8± ±23,0a6B

Average daily gain, g 56,6 57,1 57,7 58,4 58,8 56,6 56,2

Feed expenses per 1 kg of live weight gain, kg 1,79 1,77 1,76 1,75 1,75 1,76 1,78

Safety, % 98 98 98 98,0 98,0 97,0 96,0

European Productivity Index, units 315,96 322,31 327,45 333,14 335,73 318,05 309,09

Note: hereinafter similar letters stand for statistically unreliable difference between groups, and different letters stand for statistically reliable difference at P< 0,05-0,001. The order of comparison of the average live weight data

between groups: group 1 is sequentially compared with groups 2-7; group 2 - with groups 3 - 7; group 3 - with groups 4-7; group 4 - with groups 5-7; group 5 - with groups 6-7; groups 6 and 7.

Broilers production with different final live weight at rational fattening terms of female chickens and male chickens with meat of good quality, minimal feed expenses is a very important problem and fundamental internal reserve for further development of poultry industry. To solve this problem is necessary to develop and introduce rational technological parameters for broilers growing depending on slaughter period and planned final live weight.

CONCLUSION

Thus, the carried out researches proved that the rational amount of floor space per bird contribute to more complete realization of genetic potential of production of broilers of modern crosses. Due to the intensive chickens growth in the best experimental groups feed conversion and productivity index are improved. At the selection of amount of floor space per bird first of all is necessary to consider the implied final poultry weight. according to productive and zootechnic factors complex that rational amount of floor space per bird for broilers of cross «Ross^^ at duration of 38 days fattening to obtain 2,2 - 2,3 kg live weight is 25 birds/m2 at growing chickens in cages, or 394,0 sm2/bird; 20 birds/m2 at growing chickens on litter.

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