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- Alm, Malin, et al.
(författare)
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Short term deprivation of the litter area after transfer to the layer facility - effects on welfare and production in pullets
- 2013
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Ingår i: World's Poultry Science Journal. - 0043-9339. ; , s. 38-38
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- In order to enable hens to find feed and water and to reduce the number of floor-laid eggs in floor systems, producers sometimes exclude pullets from the litter area for some time when they are moved into the production system. This could have negative consequences since litter is an important resource for layers and the procedure is not allowed in Sweden. The aim of the present study was to investigate how bird welfare and production are affected by deprivation of access to litter and space at introduction of pullets to the laying facility. The study comprised 600 floor reared Bovans Robust layers obtained at 16 weeks of age (wks) and housed in 6 groups of 100 in a single-tier floor laying system. Three groups had full access to the litter area during the whole study (OPEN) and three groups were excluded from the litter during the first two weeks (CLOSED) and then received full access throughout the rest of the study. The experiment will run a full production cycle (75 wks) and figures presented below show the results obtained until 51 wks as it is still in progress. Feather cover (6-24 points), pecking wounds, cleanliness, foot condition and keel bone deviations (all 1-4 points) were assessed by integument scoring at 40 wks. Fearfulness was assessed by testing novel object (NO) and tonic immobility (TI). Based on group means, the data were analyzed by analysis of variance (ANOVA) using the MIXED procedure of the statistical system (SAS 9.2). The feather cover score was higher in treatment CLOSED (17.9 points) compared to OPEN (12.3 points) (P=0.019). No difference was found between treatments in any of the other integument score parameters. Fearfulness was higher in groups in the OPEN treatment as compared to CLOSED, indicated by less approaches in the NO test (21.5 vs 48.0) (P<0.001) and longer duration of TI (11.3 min vs 6.4 min) (P=0.018). Rate of lay, number of mislaid eggs, proportion of cracked or dirty eggs and mortality were recorded regularly but no significant differences between treatments were shown. Thus, excluding hens from the litter area during the first two weeks in this type of production system did not decrease the number of floor laid eggs, but had a positive impact on feather cover and resulted in less fearful birds. Additional welfare parameters will be analyzed later on which may explain these results further.
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| 2. |
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| 3. |
- Berg, Lotta, et al.
(författare)
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Optimal stocking density for broilers – optimal for whom?
- 2012
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Ingår i: World's Poultry Science Journal. - 0043-9339. ; 68, s. 1-6
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Tidskriftsartikel (refereegranskat)abstract
- Stocking density is not the sole crucial factor for broiler (Gallus gallus domesticus) welfare; management and environmental factors are certainly also very important. When talking about optimal stocking density it is vital to realize that the birds have no choice in this, as in practice economical factors play the most important role in the producer's decision making process. We must acknowledge that from the producer's perspective the ethical reasoning behind these choices are based on a view that animals may be used by humans for our purposes as long as they are properly cared for, i.e. fed, given water and are kept in good health. For the general public, good animal welfare for may be defined as ‘animals kept happy and healthy'. Ethical decisions are complex and ethical arguments may weigh differently for different stakeholders, leading them to very different conclusions regarding optimal stocking density and broiler welfare.
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| 4. |
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| 5. |
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| 6. |
- Blokhuis, Harry
(författare)
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Welfare Quality®
- 2012
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Ingår i: World's Poultry Science Journal. - 0043-9339. ; 68, s. 1-7
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Tidskriftsartikel (refereegranskat)
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| 7. |
- Elwinger, Klas
(författare)
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A brief history of poultry nutrition over the last hundred years
- 2016
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Ingår i: World's Poultry Science Journal. - 0043-9339. ; 72, s. 701-720
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Forskningsöversikt (refereegranskat)abstract
- The science and practice of poultry nutrition has changed greatly over the last hundred years, moving from a backyard enterprise to the modern computer-controlled production of whole diets formulated to specific nutrient compositions. This has become possible as a result of the identification of individual nutrients and their metabolic roles. Although the word 'protein' was first used in 1834, it was not until the 1950s that the avalanche of research on protein and amino acid requirements of poultry started. Energy content of feeds did not become a consideration until the 1940s when the concept of metabolisable energy was introduced. The term 'vitamin' was first proposed in 1912 to describe the essentiality of thiamine. The term was later extended to cover other essential compounds needed in small quantities. By the 1940s all the remaining 12 vitamins had been identified, and in the 1970s the importance of the vitamin D metabolites was discovered. The importance of calcium and phosphorus for both growing and laying birds was identified in the early stages of poultry keeping and requirements and dietary ratios were established. More recently, the introduction of feed phytase has allowed lowering of both phosphorus and calcium concentrations. Carbohydrase enzymes have also been development for addition to feeds. The importance of sodium, phosphorus and chloride in maintaining electrolyte balance was identified. Trace minerals were usually supplemented in diets as inorganic salts but organic chelates or proteinates have been found in recent years to be absorbed more efficiently. Antibiotics were widely used as growth promoters but their banning, especially in Europe, has led to the search for alternative additives with growth or health benefits. Poultry nutrition is now a scientifically mature subject but changes in industrial practice can be expected to continue, though probably at a slower pace than in recent years.
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