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FiguresFIGURE 1: APPROPRIATE RESTRAINT OF FREE RANGE LAYER HEN FOR WING VEIN BLOOD SAMPLING. ...................... 9FIGURE 2: THE NEEDLE IS INSERTED INTO THE WING VEIN TOWARDS THE BODY OF THE HEN AND BLOODWITHDRAWN. .................................................................................................................................................. 9FIGURE 3: COLLECTION OF FAECAL SAMPLES FOR DETERMINATION OF PARASITE BURDEN. ................................... 10FIGURE 4: EXAMPLE OF INDIVIDUAL PLASTIC NEST BOXES IN A FREE RANGE SHED. ............................................... 15FIGURE 5: HYLINE LAYERS, PERCHES, FEED AND WATERING SYSTEMS IN A FREE RANGE SHED............................... 16FIGURE 6: BOND BLACK LAYERS ON A FREE RANGE FARM. ..................................................................................... 16FIGURE 7: CHRONIC PERITONITIS: PERITONEUM COVERED WITH CONSIDERABLE FIBRINOUS MATERIAL AND YOLK 23FIGURE 8: FOLLICLES ARE DEGENERATIVE AND DISCOLOURED (OOPHORITIS) CAUSED BY OPPORTUNISTICINFECTION. .................................................................................................................................................... 23FIGURE 9: FOLLICLES ARE MISSHAPEN, DISCOLOURED OR HAEMORRHAGIC ( OOPHORITIS) .................................... 23FIGURE 10: CASE OF SALPINGOPERITONITIS: OVIDUCT BLOCKED WITH CASEOUS MATERIAL. ................................. 24FIGURE 12: ENCLOSED YOLKS CONTAINING CASEOUS MATERIAL IN A THICKENED CAPSULE .................................. 24FIGURE 13: PECKING AROUND THE VENT ASSOCIATED WITH CANNIBALISM. .......................................................... 25FIGURE 14: VENT COMPLETELY PECKED OUT AND OVIDUCT AND INTESTINES EATEN LEADING TO DEATH. ............ 25FIGURE 15: THIS BIRD HAS BEEN VENT PECKED. AFTER THE OVIDUCT AND LARGE INTESTINE WERE EATEN THEREST OF THE SMALL INTESTINE FILLED WITH BLOOD. .................................................................................... 25FIGURE 16: INTESTINE FILLED WITH PARASITE. ...................................................................................................... 26FIGURE 17: INTESTINE FILLED WITH ASCARIDIA GALLI (ROUNDWORMS)................................................................ 26FIGURE 18: ASCARIDIA GALLI FROM INTESTINE. ..................................................................................................... 26FIGURE 19: HEAD INJURIES ASSOCIATED WITH AN ATTACK BY PREDATORS. .......................................................... 27FIGURE 20: OVARY AND OVIDUCT HYPOPLASIA ASSOCIATED WITH STRESS AND CACHEXIA. .................................. 27FIGURE 21: HAEMORRHAGE IN THE ABDOMEN CAUSED BY MECHANICAL TRAUMA. ............................................... 27viii
IntroductionIndustry ProfileFree-range is the poultry housing system most actively supported by welfare groups. Birds in freerangesystems are housed in sheds and have access to an outdoor range (Model Code of Practice forthe Welfare of Animals: Domestic <strong>Poultry</strong> 4 th Ed). This is a traditional system for egg productionwhich still today provides a vision of „farm fresh eggs‟ associated with it, where hens can wander atwill over green pastures with no environmental restrictions (Kilgour and Dalton, 1984).Irrespective of a likely gradual increase in demand for free range eggs to eventually become asignificant part of the Australian egg market, free range is nevertheless an important sector as it allowsconsumers the opportunity to exercise their buying preferences; this provision of adequate choice islikely to be an important factor in managing the industry welfare debate. Currently there are 1.69million free range hens in Australia (11% of total laying hens in Australia) with an estimated grocerymarket share of 14.5%. Free range eggs are worth 23% of the value of the Australian egg industry,which is more than $71 million a year.Margins are slim due to higher production costs, and mortality in free-range systems can be high (21%Kjaer and Sorensen, 2002, 32% Sommer and Vasicek, 2000, and 15-20% Kristensen, 1998) which isunacceptable to the producer, industry and public where negative impacts can be monetary, ethicaland/or environmental. Egg production is lower and feed intake is higher under current free rangeconditions than in cage systems for a number of reasons, including different environmental challenges,energy requirements, strains and husbandry. Large-scale free range production may also beenvironmentally unfriendly.There is limited scientifically sound information on causes of mortality in free-range flocks inAustralia.Causes of mortalityFeather pecking and/or cannibalismFeather pecking is one of the most serious behavioural problems in commercial laying hens,particularly in loose-housing systems where many hens can be affected by only a few hens that engagein feather pecking (McAdie and Keeling, 2000, and Pötzsch et al., 2001). There are four types of birdto-birdpecking. 1. Aggressive pecking is directed by dominant birds at subordinates, and its objectiveis to establish and maintain dominance and can lead to severe injury or death if the recipient cannotescape. 2. Feather pecking without removal of feathers causes little or no damage and is sometimesdirected at particles of litter or food lying on the plumage or around the beak. 3. Feather pullingleading to feather loss is much more forceful pecking. The feather is grasped and firmly pulled, andthis may cause the recipient to squawk and withdraw. Hens can become almost completely denuded asa result of this pecking (McAdie and Keeling, 2000). 4. Forceful pecking is often persistently directedat exposed skin and this can lead to haemorrhage. The removal of feathers by feather pecking canresult in bleeding from the skin and follicles (especially with immature feathers), which maypredispose hens to cannibalism (McAdie and Keeling, 2000). In the flock, feather pecking may resultin increased mortality, decreased egg production and increased food consumption (Appleby andHughes, 1991, Bilčík and Keeling, 1999 and Pötzsch et al., 2001). <strong>Hub</strong>er-Eicher and Audige (1999)investigated the potential risk factors for the occurrence of feather pecking in laying hens raised undercommercial conditions on a Swiss farm with more than 500 rearing places. The factors examinedconsidered the most important as being likely to influence feather pecking included stocking density,light intensity, intensity of care, access to elevated perches, access to a roofed and littered outdoorarea, time of access to feeding facilities of the housing system, stocking density in the restricted area atthe beginning of the rearing period and air quality. The study identified two risk factors and concludedthat chicks should be reared at low density and with access to elevated perches.1
Page 1 and 2: AUSTRALIAN POULTRY CRCFINAL REPORTP
Page 3 and 4: Executive SummaryFree-range is the
Page 5 and 6: Table of ContentsEXECUTIVE SUMMARY
Page 7: TablesTABLE 1: DISTRIBUTION OF NATI
Page 11 and 12: Avian influenzaIn domestic poultry,
Page 13 and 14: ManagementThis includes factors suc
Page 15 and 16: ObjectivesThe objective of this pro
Page 17 and 18: Figure 1: Appropriate restraint of
Page 19 and 20: ResultsNationwide SurveyGeneralFour
Page 21 and 22: Table 5: Measures taken in between
Page 23 and 24: The similar symptoms shown by both
Page 25 and 26: inactivated vaccination should be l
Page 27 and 28: Initial Final Initial Final Initial
Page 29 and 30: Start Finish Start Finish Start Fin
Page 31 and 32: Figure 7: Chronic peritonitis: peri
Page 33 and 34: Figure 13: Pecking around the vent
Page 35 and 36: Figure 19: Head injuries associated
Page 37 and 38: act as mechanical vectors of other
Page 39 and 40: Appendix AFree-range layer mortalit
Page 41 and 42: 4. MANAGEMENTa) Are birds beak trim
Page 43 and 44: Appendix BPublicity LetterThe Austr
Page 45 and 46: Appendix DPublicity flyer (P.I.X.)M
Page 47 and 48: Appendix FSurvey reminder letterDea
Page 49 and 50: 2. HOUSING OF SURVEY FLOCKa) Shed t
Page 51 and 52: Appendix HExample of mortality reco
Page 53 and 54: 3. Further recordsa. Sample collect
Page 55 and 56: 15 Found dead. Liver white foci and
Page 57 and 58: Repro organs atrophied; intestinesm
Page 59 and 60:
ReferencesAllen, J. and Perry, G.C.
Page 61 and 62:
Sommer, F. and Vasicek, L. 2000. Ma
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