Online Version ISSN: 1314-412Xolume , Number

September 2012V 4 3

2012

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Editor-inChief

Tsanko YablanskiFaculty of AgricultureTrakia University, Stara ZagoraBulgaria

Co-Editor-in- Chief

Radoslav SlavovFaculty of AgricultureTrakia University, Stara ZagoraBulgaria

Editors and Sections

Genetics and Breading

Atanas Atanasov (Bulgaria)Ihsan Soysal (Turkey)Max Rothschild (USA)Stoicho Metodiev (Bulgaria)

Nutrition and Physiology

Nikolai Todorov (Bulgaria)Peter Surai (UK)Zervas Georgios (Greece)Ivan Varlyakov (Bulgaria)

Production Systems

Dimitar Pavlov (Bulgaria)Dimitar Panaiotov (Bulgaria)Banko Banev (Bulgaria)Georgy Zhelyazkov (Bulgaria)

Agriculture and Environment

Georgi Petkov (Bulgaria)Ramesh Kanwar (USA)

Product Quality and Safety

Marin Kabakchiev (Bulgaria)Stefan Denev (Bulgaria)Vasil Atanasov (Bulgaria)

English Editor

Yanka Ivanova (Bulgaria)

2012

Volume 4, Number 3September 2012

Online Version ISSN: 1314-412X

Production Systems

Performance of three commercial hybrid layers housed in conventional and enriched cage systems

1 2H. Lukanov *, D. Alexieva

1Bulgarian Association of Poultry Breeders, 5000 Veliko Tarnovo, Bulgaria2 Department of Animal Science, Faculty of Agriculture, Trakia University,6000 Stara Zagora, Bulgaria

Abstract. A study was performed on 6 groups of 12,000 commercial hybrid layers – Isa Brown, Lohmann Brown and Lohmann LSL Classic, housed in conventional and enriched cage systems in a poultry farm at the village of Polikraishte. It was established that Lohmann LSL Classic hybrid layers housed in enriched cages exhibited higher egg production than those kept in conventional cages. For the Isa Brown and Lohmann Brown hybrids, the production system used did not have an influence on egg production. The eggs' weight in the three studied hybrids – Isa Brown, Lohmann Brown and Lohmann LSL Classic was not affected by the rearing technology. The housing in enriched cages resulted in higher feed consumption in the Isa Brown and Lohmann Brown hybrids compared to housing in conventional cages. The mortality rate for the three hybrids housed in enriched cages was lower, yet feed conversion was higher compared to conventional cages. The plumage condition of the three hybrids was worse at the end of the egg-laying period in conventional cage systems.

Keywords: layer hens, egg performance, enriched cages

AGRICULTURAL SCIENCE AND TECHNOLOGY, VOL. 4, No 3, pp 246 - 249, 2012

Pohle and Cheng, (2009) and Becker et al. (2011) reported a higher Introductionegg production rate in layers reared in enriched (furnished) cages than in those housed in conventional battery cages. Until recently, housing in battery cages was considered the

The weight of eggs is highly influenced by both production most intense, most effective and most appropriate production technology and stress, so it is difficult to determine the precise effect technology for layer hens, due to a number of advantages. They of the production system on this parameter (Holt et al., 2011). included most efficient usage of facility area, the option for full Guesdon and Faure (2004) did not establish any differences in the automation of the processes, more reliable veterinary control, lower size of eggs laid by hens reared in either conventional or enriched feed consumption, no need for bedding, lower electricity cages. Layer hens reared in traditional battery cages (NFU, 2003) consumption, limiting adverse phenomena such as cannibalism, exhibited a higher daily feed consumption (114.97 g) compared to broodiness, etc. Since its advent, this technology has had its those reared in enriched cages (113.82 g). In another study, (Jendral opponents, who criticised it mainly because it was not environment-et al., 2002) a higher feed consumption is reported for hens reared in friendly. Animal rights movements and organisations have tried to enriched cages compared to the conventional system. Croxall and force producers to cease its application, yet the use of battery cages Elson (2003) did not report any difference in feed conversion and the remained a widely used method until the approval of Council mortality rate in layers related to conventional or enriched cage Directive 1999/74 (Council Directive 1999/74/EC) laying down systems. minimum standards for protection of layer hens. It also banned

Many researchers (Fleming et al., 1994; Newberry, 1995; housing layer hens in conventional battery cages effective from 1 Leyendecker et al., 2005; Vits et al., 2005) believe that enriched January 2012.cages provided better conditions with regard to poultry welfare, The only option of preserving caged rearing in some form were reduced the episodes of fear, aggression, pterophagia and have a enriched cages, also known as comfortable or furnished cages, beneficial overall effect on birds' survival and plumage condition. On which provide more space for the birds and satisfy their biological the contrary, Jendral et al. (2002) reported a better plumage needs by including perches, nests, pecking and digging material, condition in layers housed in conventional vs enriched cage and dust bathing (Appleby et al., 1993; Appleby and Hugles, 1995; systems. The brief overview of the literature reveals that although in Abrahamsson et Tauson, 1995; Appleby, 1998; Appleby et al., 2002).most cases the production of layers in enriched cages seemed as Farm Animal Welfare Council (2007) divides enriched cages good as that of birds reared in batteries, there are several unclear into several categories: small – for up to 15 layer hens, medium – for issues related to feed consumption and conversion, the plumage 15-30 layer hens and large – for more than 30 layer hens. There are condition and the genotype/production system interaction. numerous studies comparing the performance of layer hens bred in

The goal of the present study was to evaluate the performance enriched or conventional cages. Some of them highlight the profile of three hybrid layers – Isa Brown, Lohmann Brown and advantages, while others – the disadvantages of enriched cages. Lohmann LSL Classic, housed in conventional and enriched cages. Leyendecker et al. (2002), Zoons (2004, cited by EFSA, 2005),

* e-mail: dr_lukanov@abv.bg

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Table 1. Controlled parameters of the three egg laying hybrids in conventional and enriched cages.

Parameters

Laying intensity (%)

Average egg weight, g

Average daily feedconsumption, g

Feed conversion ratio,g per 1 egg*

Feed conversion ratio,g per kg egg weight*

Livability, %

a85.41 ± 2.01

61.75 0.67 ±

115.27 0.87 ±

b130.97 1.74 ±

2075.24 37.71 ±

94.38

83.03 2.39 ±

62.66 0.74 ±

a117.92 1.04 ±

137.40 2.11 ±

2157.57 ± 28.08

93.98

83.67 3.18 ±

62.98 0.62 ±

a117.42 1.06 ±

135.12 2.57 ±

2226.2 ± 33.88

95.69

a79.61 ± 1.76

61.50 0.76 ±

113.10 0.83 ±

ab139.61 1.49 ±

2256.91 32.06 ±

93.50

81.21 ± 2.31

62.58 0.70 ±

113.93 0.94 ±

137.40 2.52 ±

2123.93 51.18 ±

91.43

81.60 ± 2.60

62.89 0.59 ±

113.25 1.00 ±

a133.24 2.04 ±

2070.62 61.52 ±

90.55

Conventional cages Enriched cages

Isa Brown Isa BrownLohmann Brown Lohmann BrownLohmann LSL

ClassicLohmann LSL

Classic

* Refers to the period 22 – 76 weeksMeans within a row with the same superscripts are significantly different (a-a – p ≤ 0.05, b – b – p ≤ 0.01)

247

greatest average egg production (85.45%), whereas the Lohmann Material and methodsBrown hybrid the lowest (77.96%). The difference between the two hybrids is considerable (7.49%). The Isa Brown hybrid assumes a The experiment was carried out with three hybrid layers – Isa medium position (82.88%). These data on laying intensity can be Brown, Lohmann Brown and Lohmann LSL Classic, housed in considered prognostic.conventional and enriched cages in the poultry farm in the village of

In general, for the entire experimental period, the three hybrids' Polikraishte. For this purpose, 6 groups of 12,000 birds each were laying performance was similar when housed in conventional cages formed. (Table 1). The difference between them in terms of egg production Conventional three-level battery cages manufactured by the was not significant. The Lohmann LSL Classic hybrid did not exhibit Parvi Mai factory in Polski Trambesh were used, as they provided an advantage, and even could not reach the expected laying automated feeding and water supply, manual egg collection and an

2 performance. When housed in enriched cages, however, the area of 450 cm per bird. The enriched cages were produced by the Lohmann LSL Classic hybrid exhibited significantly higher egg German company Big Dutchman – model EV 625A-EU, 3-level, production, compared to the conventional cage system (р≤0.05) with individual ventilation for each cage, manure drying, and four and fully achieved its prognostic laying capacity. The worse results chambers (cages) per compartment. A section contains two parallel registered under the conditions of conventional cages could be compartments, with 40 hens kept in each section (2 x 20), with 750

2 th th explained with higher stress sensitivity of the white hybrids. The data cm area per bird. The experiment took place from the 18 to 76 indicate that both brown hybrids had better egg production when week of age. The layers from all groups were fed compound feed, housed in enriched cages than in conventional ones, yet the prepared at the farm in accordance with the requirements for this differences were not significant. In both brown hybrids, Lohmann category of birds. During the experiment, the following parameters Brown and Isa Brown, the intensity of laying in enriched cages was were controlled: egg laying performance (%), egg weight (g), feed higher than the data reported in their technical specifications. The consumption per egg and per egg mass (g), feed conversion, results of our study confirmed the findings of other authors liveability (%) and plumage condition.(Leyendecker et al., 2002; Zoons, 2004; Pohle and Cheng, 2009; Egg production (%) was measured weekly via daily control of Becker et al., 2011), who also proved that the egg performance of the number of laid eggs and the number of birds. Egg weight was layer hens was higher when they were housed in enriched cages measured weekly via daily weighing, with accuracy of up to 0.5 g, of than in conventional ones.representative samples of laid eggs. The livability was recorded

The data on the eggs' weight in the birds from the three hybrid monthly by counting dead birds. The feed consumption per hen layers reared in conventional and enriched cages are presented in housed was calculated based on the weekly feed consumption and Table 1 and Figure 1. According to the hybrids' performance data, the number of birds. Feed consumption per egg was calculated provided by the producers, the Lohmann Brown hybrid has the weekly based on the amount of consumed feed and the number of greatest average egg weight (63.76 g), whereas Lohmann LSL laid eggs for the same period. The plumage condition was assessed Classic the lowest average egg weight – (62.33 g). These two at 26, 56 and 76 weeks of age on a scale from 1 to 4 (with 4 being hybrids, housed both in conventional and enriched cages, did not very good, 3 – good, 2 – bad, and 1 – very bad). The results were reach the prognostic egg weight. The differences from the standard, statistically processed.however, were not statistically significant. The average egg weight was insignificantly higher when the birds were housed in enriched cages, compared to the egg weight in birds in conventional cages. Results and discussionThis was more pronounced in the Lohmann LSL Classic hybrid. The differences in the egg weight, between the two evaluated systems, According to the characteristics of the hybrids, provided by the as well as among the three hybrids, however, were not significant. genetic material producers, the hybrid Lohmann LSL Classic has the

248

With the Isa Brown hybrid, for both technologies, the egg weight feed consumption per egg in conventional cages, as evidenced by reached the desired values earlier than the other two hybrids, as the data for the feed conversion per kg egg mass. The production visible from Figure 1. Our results did not confirm the reported technology did not have any practical effect regarding the feed findings (Laywel, 2004), about higher egg weight with traditional consumption per egg in both brown hybrids. These results were not battery cages. unexpected because brown hybrids are considerably less sensitive

According to the hybrids' production data provided by the to stress than the white ones. The data on feed conversion genetic material producers, the Lohmann Brown hybrid has the correspond to the data on the three hybrids' egg laying performance highest daily feed consumption (113 g), whereas Lohmann Classic for both technologies, the reason for that being the highly beneficial has the lowest (106.9 g). The Isa Brown hybrid assumes a medium correlation between laying performance and feed consumption per position (111 g). These data on the average daily feed consumption egg.by a layer hen can be used as basic reference. When housed in According to the hybrids' technical specifications provided by conventional cages, the three hybrids' average daily feed the genetic material producers, all three hybrids exhibited high consumption was similar without significant differences (Table 1). A livability – 95% for Lohmann Brown and Lohmann Classic, and lower average daily feed consumption was not observed for the 93.3% for Isa Brown. These livability data can be considered as Lohmann Classic hybrid, as was expected according to its reference. In all three hybrids, for both tested production systems, performance data. In enriched cages, the daily feed consumption the birds' livability was lower than that claimed by the genetic was higher by 2.95% on average, compared to that in conventional material producers (Table 1) . Breeding in enriched cages had a cages. For the Isa Brown and Lohmann Brown hybrids, the beneficial effect on the birds' livability, which was higher with this

technology. This was more visibly exhibited in the Isa Brown hybrid. established differences in this parameter were significant (Р≤The difference in the birds' liveability percentages in favour of the 0.05). Our results confirmed the higher consumption of feed by hens enriched cages could be explained with the maintenance of better housed in enriched cages, found by Jendral et al. (2002). Table 1 zoohygienic parameters, the lower effect of stress factors and the also presents the data on feed conversion for the three hybrids for improved comfort.Our findings did not confirm the results of other both tested production systems. With housing in conventional studies, which had not detected a difference in the birds' mortality cages, the feed consumption per egg and per 1 kg egg mass was the rates for both breeding technologies (Croxall and Elson, 2003) or lowest in the Isa Brown hybrid, while the highest for Lohmann LSL predicted higher risk in enriched cages (Laywel, 2006).Classic. The difference between the two hybrids for feed

Table 2 presents data on the birds' plumage condition for both consumption per egg was significant (Р≤ 0.05). With housing in tested technologies. The data showed that when the three hybrids enriched cages, the feed consumption per egg in the Lohmann LSL were housed in conventional cages, the plumage condition at the Classic hybrid decreased significantly (Р≤0.01) compared to the

Figure 1. Average egg weight, g (Conventional cages, CC; Enriched cages, EC)

g

70

65

60

55

50

45

40

week

Isa brown CC

Lohmann Brown EC

Isa Brown EC

Lohmann LSL CC

Lohmann Brown CC

Lohmann LSL EC

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58

Table 2. Plumage condition

*CC – Conventional cages, **EC – Enriched cages

Age

(weeks)

26

56

76

4

3

2

4

3

2

4

3

2

4

3

3

4

3

3

4

3

3

Isa Brown

CC* CC* CC*EC** EC** EC**

Lohmann Brown Lohmann LSL Classic

249

end of the production period was bad, whereas in enriched cages it Communities, L 203, 53–57.remained in good condition over the entire period. Our results did not EFSA, 2005. Welfare aspects of various systems for keeping laying confirm the better condition of the hens' plumage kept in hens (Scientific report EFSA-Q-2003-92. The EFSA Journal 2005, conventional cages, established by Jendral et al. (2002). 1-23. http://www.efsa.europa.eu/en/efsajournal/doc/197.pdf (10

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Section A, Animal Science, 45, 191-203.defined housing system for laying hens, and detailing the overall

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Preparation of papersPapers shall be submitted at the editorial office typed on standard typing pages (A4, 30 lines per page, 62 characters per line). The editors recommend up to 15 pages for full research paper ( including abstract references, tables, figures and other appendices)

The manuscript should be structured as follows: Title, Names of authors and affiliation address, Abstract, List of keywords, Introduction, Material and methods,Results, Discussion, Conclusion, Acknowledgements (if any), References, Tables, Figures.The title needs to be as concise and informative about the nature of research. It should be written with small letter /bold, 14/ without any abbreviations. Names and affiliation of authorsThe names of the authors should be presented from the initials of first names followed by the family names. The complete address and name of the institution should be stated next. The affiliation of authors are designated by different signs. For the author who is going to be corresponding by the editorial board and readers, an E-mail address and telephone number should be presented as footnote on the first page. Corresponding author is indicated with *. Abstract should be not more than 350 words. It should be clearly stated what new findings have been made in the course of research. Abbreviations and references to authors are inadmissible in the summary. It should be understandable without having read the paper and should be in one paragraph. Keywords: Up to maximum of 5 keywords should be selected not repeating the title but giving the essence of study. The introduction must answer the following questions: What is known and what is new on the studied issue? What necessitated the research problem, described in the paper? What is your hypothesis and goal ?Material and methods: The objects of research, organization of experiments, chemical analyses, statistical and other methods and conditions applied for the experiments should be described in detail. A criterion of sufficient information is to be

possible for others to repeat the experi-ment in order to verify results.Results are presented in understandable tables and figures, accompanied by the statistical parameters needed for the evaluation. Data from tables and figures should not be repeated in the text.Tables should be as simple and as few as possible. Each table should have its own explanatory title and to be typed on a separate page. They should be outside the main body of the text and an indication should be given where it should be inserted.Figures should be sharp with good contrast and rendition. Graphic materials should be preferred. Photographs to be appropriate for printing. Illustrations are supplied in colour as an exception after special agreement with the editorial board and possible payment of extra costs. The figures are to be each in a single file and their location should be given within the text. Discussion: The objective of this section is to indicate the scientific significance of the study. By comparing the results and conclusions of other scientists the contribution of the study for expanding or modifying existing knowledge is pointed out clearly and convincingly to the reader.Conclusion: The most important conse- quences for the science and practice resulting from the conducted research should be summarized in a few sentences. The conclusions shouldn't be numbered and no new paragraphs be used. Contributions are the core of conclusions. References:In the text, references should be cited as follows: single author: Sandberg (2002); two authors: Andersson and Georges (2004); more than two authors: Andersson et al.(2003). When several references are cited simultaneously, they should be ranked by chronological order e.g.: (Sandberg, 2002; Andersson et al., 2003; Andersson and Georges, 2004).References are arranged alphabetically by the name of the first author. If an author is cited more than once, first his individual publications are given ranked by year, then come publications with one co-author, two co-authors, etc. The names of authors, article and journal titles in the Cyrillic or alphabet different from Latin, should be transliterated into Latin and article titles should be translated into English. The original language of articles and books translated into English is indicated in

parenthesis after the bibliographic reference (Bulgarian = Bg, Russian = Ru, Serbian = Sr, if in the Cyrillic, Mongolian = Мо, Greek = Gr, Georgian = Geor., Japanese = Jа, Chinese = Ch, Arabic = Аr, etc.)The following order in the reference list is recommended:Journal articles: Author(s) surname and initials, year. Title. Full title of the journal, volume, pages. Example:Simm G, Lewis RM, Grundy B and Dingwall WS, 2002. Responses to selection for lean growth in sheep. Animal Science, 74, 39-50Books: Author(s) surname and initials, year. Title. Edition, name of publisher, place of publication. Example: Oldenbroek JK, 1999. Genebanks and the conservation of farm animal genetic resources, Second edition. DLO Institute for Animal Science and Heal th, Netherlands.Book chapter or conference proceedings: Author(s) surname and initials, year. Title. In: Title of the book or of the proceedings followed by the editor(s), volume, pages. Name of publisher, place of publication. Example: Mauff G, Pulverer G, Operkuch W, Hummel K and Hidden C, 1995. C3-variants and diverse phenotypes of unconverted and converted C3. In: Provides of the Biological Fluids (ed. H. Peters), vol. 22, 143-165, Pergamon Press. Oxford, UK.Todorov N and Mitev J, 1995. Effect of level of feeding during dry period, and body condition score on reproductive perfor-

thmance in dairy cows,IX International Conference on Production Diseases in Farm Animals, Sept.11 – 14, Berlin, Germany, p. 302 (Abstr.).Thesis:Penkov D, 2008. Estimation of metabolic energy and true digestibility of amino acids of some feeds in experiments with muscus duck (Carina moshata, L). Thesis for DSc. Agrarian University, Plovdiv, 314 pp.

The Editorial Board of the Journal is not responsible for incorrect quotes of reference sources and the relevant violations of copyrights.

Volume 4, Number 3September 2012