Husbandry and Genetic Strategies to Improving Hide Quality of Ostriches

Husbandry and Genetic Strategies to Improve Hide Quality of Ostriches RIRDC Publication No. 09/174

RIRDC

Innovation for rural Australia

Husbandry and Genetic Strategies to Improve Hide Quality of Ostriches By Philip Glatz

January 2010 RIRDC Publication No 09/174 RIRDC Project No. PRJ-000563

© 2010 Rural Industries Research and Development Corporation. All rights reserved.

ISBN 1 74151 971 3 ISSN 1440-6845 Husbandry and Genetic Strategies to Improving Hide Quality of Ostriches Publication No. 09/174 Project No. PRJ-000563 The information contained in this publication is intended for general use to assist public knowledge and discussion and to help improve the development of sustainable regions. You must not rely on any information contained in this publication without taking specialist advice relevant to your particular circumstances. While reasonable care has been taken in preparing this publication to ensure that information is true and correct, the Commonwealth of Australia gives no assurance as to the accuracy of any information in this publication. The Commonwealth of Australia, the Rural Industries Research and Development Corporation (RIRDC), the authors or contributors expressly disclaim, to the maximum extent permitted by law, all responsibility and liability to any person, arising directly or indirectly from any act or omission, or for any consequences of any such act or omission, made in reliance on the contents of this publication, whether or not caused by any negligence on the part of the Commonwealth of Australia, RIRDC, the authors or contributors. The Commonwealth of Australia does not necessarily endorse the views in this publication. This publication is copyright. Apart from any use as permitted under the Copyright Act 1968, all other rights are reserved. However, wide dissemination is encouraged. Requests and inquiries concerning reproduction and rights should be addressed to the RIRDC Publications Manager on phone 02 6271 4165. Researcher Contact Details Dr Phil Glatz South Australian Research and Development Institute, PPPI Roseworthy Campus Roseworthy, SA 5371 Phone: (08) 83037786 Fax: (08) 83037689, Email: [email protected] In submitting this report, the researcher has agreed to RIRDC publishing this material in its edited form. RIRDC Contact Details Rural Industries Research and Development Corporation Level 2, 15 National Circuit BARTON ACT 2600 PO Box 4776 KINGSTON ACT 2604 Phone: Fax: Email: Web:

02 6271 4100 02 6271 4199 [email protected]. http://www.rirdc.gov.au

Electronically published by RIRDC in January 2010 Print-on-demand by Union Offset Printing, Canberra at www.rirdc.gov.au or phone 1300 634 313

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Foreword In Australia ostrich hides exhibit varying degrees of skin damage. One reason that was causing the downgrading of hides was the presence of pinholes caused by filoplumes and bristle hairs. The levels of bristle hairs and filoplumes noted in this project were approximately 15% and 5% of the progeny respectively. The incidence of filoplume and bristle hairs indicate the possibility of genetic differences between the Australian strains of ostrich and the imported stains although this was not consistent across all farms. Downgrading of hides also results from the presence of small scars. These are caused mainly by ostrich claws and also abrasions from objects in the environment. In other bird species declawing is practised to minimise skin lesions caused by claws. The behavioural evidence from this project suggests that declawing does not compromise the welfare of yearling ostriches and resulted in a 25% improvement in quality of skins. This report was funded from RIRDC Core Funds provided by the Australian Government. This report, an addition to RIRDC’s diverse range of over 1900 research publications, forms part of our New Animal Products R&D program, which aims to accelerate the development of viable animal industries. Most of RIRDC’s publications are available for viewing, downloading or purchasing online at www.rirdc.gov.au. Purchases can also be made by phoning 1300 634 313.

Peter O’Brien Managing Director Rural Industries Research and Development Corporation

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Acknowledgments Acknowledgment is given to the following colleagues and organisations that provided support, assistance, encouragement and advice during the project. •

Dr. Peter McInnes, Program Manager, New Animal Products Program of the Rural Industry Research and Development Corporation for providing funds to undertake this work and helpful advice

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June Murphy, Program Coordinator, New Animal Products Program of the Rural Industry Research and Development Corporation for administrative support throughout the project

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Dr. Kim Bunter, Animal Breeding and Genetics Unit, University of New England, for advice on data recording for filoplumes

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Dr. Doug Black and Chris Tuckwell for scoring of filoplumes

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Belinda Rodda and Dr Zhihong Miao from the Pig and Poultry Production Institute who provided technical support

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Mark Bradley for undertaking the filming of ostrich behaviour.

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Contents Foreword ............................................................................................................................................... iii Acknowledgments................................................................................................................................. iv Executive Summary ............................................................................................................................ vii 1. Introduction ....................................................................................................................................... 1 2. Objectives ........................................................................................................................................... 3 3. Review ................................................................................................................................................ 4 3.1. Declawing .................................................................................................................................. 4 3.2 Welfare issues ............................................................................................................................. 4 3.3 Filoplumes .................................................................................................................................. 5 3.4 Pinholes ....................................................................................................................................... 6 3.5 Bristle Hairs ................................................................................................................................ 6 3.6 Genetics ...................................................................................................................................... 6 3.7 Economic Implications ............................................................................................................... 7 4. Materials and Methods ..................................................................................................................... 8 4.1 Filoplume and Bristle Hair Study ............................................................................................... 8 4.2 Declawing Study ......................................................................................................................... 9 4.3 Skin Quality of Declawed Birds ............................................................................................... 11 4.4 Statistical Analysis of behaviour and skin grades .................................................................... 12 5. Results and Discussion .................................................................................................................... 13 5.1 Filoplume/Bristle Hair Study.................................................................................................... 13 5.2 Declawing Study ....................................................................................................................... 19 6. Implications...................................................................................................................................... 26 7. Recommendations ........................................................................................................................... 27 8. References ........................................................................................................................................ 28

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Tables Table 1.

Effect of breed and year on filoplume score for farm A................................................... 17

Table 2.

Effect of breed and year on bristle hair score for farm A. ................................................ 17

Table 3.

Effect of breed on filoplume and bristle hair score for farm B measured from progeny over one year ..................................................................................................................... 18

Table 5a.

Effect of declawing on day-old ostrich chick behaviour (bouts) averaged over 1h intervals from 2000h-0800h on day of operation ............................................................. 20

Table 5b.

Effect of declawing on ostrich chick behaviour (bouts) averaged over 1h intervals from 2000h-0800h on the day of the operation ................................................................ 20

Table 6.

Effect of declawing on bouts that ostrich chicks (1-2 weeks-of-age) engaged in inactive, ingestive, grooming, aggressive and locomotor behaviours averaged over 1h intervals for 8h (0800-0400h) in the indoor brooder area and outside run. ................ 23

Table 7.

Effect of declawing on bouts and time (secs) year old ostriches engaged in inactive, ingestive, grooming, aggressive and locomotor behaviours over 30 min......................... 24

Table 8.

Skin Quality of declawed birds......................................................................................... 25

Figures Figure 1:

Characteristics of filoplumes and bristle hairs at various stages of maturity ................... 16

Figure 2.

Percentage of skin grades from declawed ostriches vs. control group (not declawed) .... 25

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Executive Summary What the report is about: In Australia up to one-third of ostrich skins do not achieve an A grade standard because of pinhole defects, which are related to the presence of filoplumes and bristle hairs. This project examined whether there were differences in filoplume scores for birds on 3 farms from various ostrich breeding groups. The progeny from various breeding groups were scored for the incidence of filoplumes and bristle hairs. In addition approximately 1/3 of ostrich skins are downgraded because of the presence of small scars on the hide some of which appear to have been caused by claw abrasions. This damage occurs during the chick brooding and rearing stage. To minimise the incidence of scars that may result from claw injuries during the chick stage, declawing was practiced on two ostrich farms to determine whether declawing affected behaviour of ostrich chicks and year-old ostriches and improved skin grades. Who is the report targeted at? This report is targeted at ostrich farmers. Background: In Australia a number of ostrich hides are downgraded due to defects. One reason for the poorer quality of hides is the presence of both large and small pinholes that are clearly detectable in the hide after tanning. Variations in these indentations may be caused by the degree and size of filoplumes and bristle hairs in the skin of ostriches. Hides are also being downgraded due to the presence of small scars. Fence trauma, barbed wire, thorn bushes, sticks or branches can cause these scars. They can also result from claw abrasions from ostrich chicks as they clamour over each other when being released from the brooding area in the morning. Alternatively they could occur during other chick interactions while they are engaged in feeding, drinking and other activities. The incidence of scars could be reduced substantially by ensuring the birds are properly managed throughout the production cycle. Factors such as stocking rates, feeding and drinking space, type of fencing, yarding, transport, lairage, handling and skinning all influence skin quality. However sorting chicks according to weight and sex has little benefit on skin quality. The husbandry practice of declawing has been suggested as a potential means of reducing some of the small scars observed on hides. A concern, however, is whether declawing may inhibit the gait and walking ability of ostriches because of chronic pain in the toe stump. Aims/objectives: 1. Evaluate the prevalence of filoplumes and bristle hairs. 2. Assess declawing of ostriches as a husbandry strategy to improve hide quality and examine the effects of declawing on walking ability and general behaviour of ostriches. 3. Establish if declawing can be justified as a husbandry practice to prevent its potential abuse. 4. To improve the welfare of farmed ostriches, worker safety and economic returns by declawing ostriches. Methods used: Data for the filoplume study was collected from three ostrich farms in Victoria, Australia. The farmers who provided the data had various combinations of pairs, trios and colony breeders. The data collected identified the breeding group from which the progeny were sourced. These progeny were scored for filoplumes and bristle hairs prior to slaughter.

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The rationale for the declawing study was to examine short and long-term effects of declawing on the behaviour of ostriches. The first observations were made on ostrich chicks over the first 8 h after the operation. The next assessment of birds was at 1-2 weeks-of-age when the declawing wound was healing and the birds had been transferred from the brooder box to the rearing pens. The final assessment of behaviour was made when birds were about 12 months-of-age when any long-term effects of declawing on behaviour and skin quality would be obvious. The assessment of the skin quality of declawed versus control birds were undertaken on a commercial ostrich farm. About 400 birds were declawed on the day of hatch by removing the distal phalangeal joint using a Lyon beak-trimming machine; another group of 300 ostriches were not declawed. Birds were maintained on starter, grower and finisher diets and reared apart throughout the trial. Skin quality of declawed birds was compared to a control group of birds. Birds were transported to an abattoir and graded according to Industry standards. Results/key findings: Filoplumes and bristle hairs High levels of bristle hairs and filoplumes (that is the presence of more than 4 hairs or 4 filoplumes is specific defined body areas) were measured in approximately 15% and 5% of the progeny. The incidence of filoplume and bristle hairs indicate the possibility of genetic differences between the Australian strains of ostrich and the imported stains although this was not consistent across all farms. The black and red ostrich breeding groups had a greater incidence of filoplumes compared to the Australian pure or crossbreeds. A seasonal variation in incidence of filoplumes noted on one farm may be related to one extremely cold winter. The role of the filoplume may be to assist with control of the orientation of the follicles and hence feather position for maintaining thermoregulation. Declawing Approximately one-third of ostrich skins are downgraded because of the presence of small scars on the hide some of which appear to have been caused by claw abrasions. This damage occurs during the chick brooding and rearing stage. To minimise the incidence of scars that may result from claw injuries during the chick stage, declawing is being practised on a number of ostrich farms. Partial amputation of the two toes of ostriches has welfare implications. It may cause the ostriches chronic pain and to become flatfooted and change their gait. On the other hand the change in gait may reduce their ability to deliver effective kicks to humans and other ostriches during aggressive encounters. A study was undertaken at Hazelwood Ostriches to determine if declawing affected behaviour of ostrich chicks and subsequently the behaviour of yearling ostriches. The evidence indicates declawing modifies chick ostrich behaviour and reduces the potential for skin damage in the first two weeks after hatching. In 12 month-old ostriches, however, there was no major significant differences detected between declawed and control ostriches in inactive, ingestive, posture change, grooming, aggressive, stereotype and locomotor behaviours. Control ostriches tended to engage in more bouts of walking (P=0.09) and chasing (P=0.13) other ostriches compared to declawed ostriches. A concern, however, was the significant increase (P=0.02) in the incidence of slipping observed in declawed adult ostriches. Overall, the behavioural evidence indicates declawing does not compromise the welfare of yearling ostriches. Some farms have reported a 25% improvement in the % of A grade skins from declawed ostriches.

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Implications for relevant stakeholders: 1. The filoplume and bristle hair results indicate the possibility of genetic differences between the Australian and imported strains of ostrich. 2. Declawing of ostriches can improve skin quality by 25% Recommendations: 1. Declawing of ostrich chicks should be conducted at day old according to the accreditation procedure developed. 2. Farmers should consider not using breeders which have a high incidence of filoplumes and bristle hairs

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1. Introduction 1.1 Ostrich Hide Quality In Australia ostrich hides exhibit varying degrees of skin damage. One reason that was causing the downgrading of hides was the presence of pinholes caused by filoplumes and bristle hairs that are clearly detectable in the hide after tanning. Variations in these indentations may be caused by the degree and size of filoplumes in the skin of ostriches. Hides are also being downgraded due to the presence of small scars. Fence trauma, barbed wire, thornbushes, sticks or branches can cause these scars. They can also result from claw abrasions from ostrich chicks as they clamour over each other when being released from the brooding area in the morning. Alternatively they could occur during other chick interactions while they are engaged in feeding, drinking and other activities. The incidence of scars could be reduced substantially by ensuring the birds are properly managed throughout the production cycle. Factors such as stocking rates, feeding and drinking space, type of fencing, yarding, transport, lairage, handling and skinning all influence skin quality. However sorting chicks according to weight and sex has little benefit on skin quality (Meyer, 2003). The husbandry practice of declawing has been suggested as a potential means of reducing some of the small scars observed on hides. A concern, however, is whether declawing may inhibit the gait and walking ability of ostriches because of chronic pain in the toe stump.

1.2 Filoplumes A major threat to the viability of the ostrich industry is that returns are not maximised from ostrich hides. Skins account for about 60% of the income from processed ostriches (Meyer, 2003) and farmers are under extra pressure to produce higher quality skins to remain profitable. Skin marketers are applying higher standards during grading. The fluctuation in the world price for skins (Black, 1999b) requires that farmers take advantage of periods when skin prices are high and attempt to maintain profitability when prices drop, by producing good quality skins. Large increases in prices for hides occurred in March 1999, followed by a fall in 2002. Potentially the Australian ostrich industry could receive an additional income AUD$2m/annum for ostrich hides by achieving higher same grading standards. One of the activities in the project was to assess the incidence of filoplumes and bristle hairs in various strains and crosses that are farmed in Australia. This trait may be under some degree of genetic control and potentially related to hide quality, such as rate of development of plumage in poultry or characteristics of the skin or other skin appendages (e.g. wool in sheep). However before implementation of breeding programs in ostriches it is necessary to establish if incidence of filoplumes is significant in the Industry. For ostriches this type of information in not available currently anywhere in the world.

1.3 Declawing The other focus of this project was to examine the influence of declawing on ostrich behaviour and hide quality. The claw is a key weapon of most bird species. In other species (emu and domestic poultry) there has been a demonstrated link between improved welfare and production as a result of declawing. For example, on-farm studies of emus have shown that gait of emus is altered, aggressive behaviours modified and skin quality improved by declawing emus (Glatz, 2001; Lunam and Glatz, 2000; O’Malley, 1999). Similarly welfare of domestic poultry has substantially improved as a result of declawing. There has been a reduction in injuries to birds during mating and overall reduction in

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aggressive behaviours. In ostriches the claw is not as sharp as other bird species and is not considered to cause the same extent of damage to the skin. On occasions, however, ostriches will lash out with their karate-like kicks, large foot and gouging toenail. Declawing might alter the weight balance in ostriches and reduce this kicking ability, decrease bruising and skin damage, and alter aggressive behaviour patterns.

1.4 Welfare Declawing involves partial removal of each toe with a red-hot blade. In other bird species the operation causes acute pain, with possible long-term chronic pain and alteration to gait. This project will establish if declawing is warranted as a husbandry practice in the Ostrich Industry. It is important that the Industry does not adopt declawing as a management strategy before research establishes if the practice does not cause welfare problems to birds. The abuse of de-clawing through use of inappropriate techniques could harm bird welfare, reduce farm profitability and give the public a poor perception of the Industry.

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2. Objectives 1. Evaluate the prevalence of filoplumes and bristle hairs in the ostrich Industry 2. Assess declawing of ostriches as a husbandry strategy to improve hide quality and examine the effects of declawing on walking ability and general behaviour of ostriches 3. Establish if declawing can be justified as a husbandry practice to prevent its potential abuse 4. To improve the welfare of farmed ostriches, worker safety and economic returns by declawing ostriches.

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3. Review 3.1. Declawing The claws of most bird species are one of the most effective defensive structures, causing stress and altering behaviour patterns in other birds of the flock (Ruszler and Quisenberry, 1979). The claws are used as weapons to inflict injury on competitors and used to maintain status in the social hierarchy. In some strains of poultry declawing has been carried out by removing the distal phalangeal joint of the front toes with a red-hot blade (Compton, et al., 1981). In day old chickens the distal phalangeal joint can also be amputated with a sharp pair of scissors angled to retain the ventral aspect of the distal phalanx within the footpad. Declawing has been reported to reduce hysteria in birds and increase production (Hansen, 1969; Ruszler and Kiker, 1975; Hansen, 1976, Ruszler and Quisenberry, 1979; Compton, et al., 1981; Gildersleeve, et al., 1981; Martin, et al., 1981; Vanskike and Adams, 1983 and Goodling, et al., 1984). However, it was reported by Compton, et al. (1981) that declawing decreased the support of the foot on wire, leading to inferior foot condition. In emus, Lunam and Glatz (2000) found that declawed emus were flat-footed and had an altered gait. In Australia, declawing is practiced in the poultry breeder industry to prevent aggressive roosters causing claw damage on hens. Some strains of layer pullets have also been declawed to alleviate the injuries to the skin of other birds caused by aggressive and panic behaviours. Declawing also reduces the risk to handlers, particularly during procedures such as retrimming, vaccination, pullet transport to the farm and spent hen transport. In the emu industry it is routine practice to declaw emus as it reduces conflict between emus, prevents damage and downgrading of hides and improves worker safety.

3.2 Welfare issues Pain Declawing can potentially result in long-term pain. Zimmerman (1986) reports that chronic pain in most species can modify specific walking behaviours, including social behaviour. Chronic pain is observed in orthopaedic disease and in some cases following peripheral injury (Gentle, 1992). Tissue and bone damage resulting from declawing could result in persistent pain with birds undertaking protective guarding behaviour and other pain coping behaviours. In heavy breeds of poultry with arthritic complaints loss of locomotor function is common (Thorp, 1994). Animals with this condition are unwilling to stand or walk and there is evidence of one legged standing, limping and sitting as the bird attempts to cope with the pain. In less painful arthritic conditions animals are observed to change their posture more frequently. Traumatic neuromas in the beak stump after trimming have been implicated as a cause of chronic pain in commercial hens (Breward and Gentle, 1985; Gentle, 1986a). Traumatic neuromas consist of swollen tangled masses of regenerating axon sprouts. These may form as either large masses or may develop as small scattered multiple fascicles of axons to form microneuromas (Devor and Rappaport, 1990). After several weeks the nerve fibres regrow, the excess axon sprouts degenerate and the neuroma regresses. Occasionally, the neuromas pose significant welfare implications as they can spontaneously discharge action potentials resulting in chronic pain. In addition, nerve fibres associated with neuromas have a decreased threshold to noxious stimuli and undergo allodynia, a condition in which normally non-noxious stimuli become painful. Studies by Lunam et al. (1996) showed neuromas were present in all beak stumps at 10 weeks, but neuromas were not found at 70 weeks after moderate trimming at hatch, whereas neuromas persisted in the adult hen after severe trimming. As neuromas were not observed in adult hens that had been moderately

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beak trimmed, the results indicate that they develop and persist for at least 10 weeks, before resolving. This would explain why neuromas were seen in beak stumps between 15 days and 10 weeks after trimming one-third of the upper beak of hens by other workers (Breward and Gentle, 1985; Gentle, 1986). In adult emus, Lunam and Glatz (2000) did not observe any traumatic neuromas in toe stumps, although some focal microneuromas were observed in declawed emus.

Behaviour Gentle (1992) suggests that chronic pain can result in pain guarding behaviours and declawing might be expected to modify walking behaviour. Studies by Lunam and Glatz (2000) however showed that despite emus becoming flatfooted, there was no behavioural evidence to indicate loss of locomotor ability of declawed emus or to suggest declawed emus were suffering from severe chronic pain because most of the neuromas had resolved by 28 weeks of age. In addition declawed emus engaged in significantly more bouts and time of searching, less stereotype pacing and pecking indicating the declawed birds were under less stress and not as frustrated as control birds which were more aggressive (Glatz, 2001). The behavioural and neurological evidence for emus indicate that declawing does not compromise the locomotor ability of emus, despite the altered gait, and has the benefit of improving the social structure in the groups by reducing stereotype behaviour and aggression. Meyer (2003) observed that ostrich chicks were able to walk and run soon after declawing.

Production Meyer (2003) compared 20 week-old declawed ostriches with a control group. The declawed group had fewer scratch and kick marks and produced twice the number of first grade skins. Declawing did not affect locomotor ability and improved liveweight and skin area. Mortality was higher in the declawed group presumably due to removal of excessive amount of claw or incomplete cauterisation.

3.3 Filoplumes Filoplumes are hair-like feathers that are considered to be normal in most orders of birds . There are very few references on the incidence of filoplumes in ostriches. One common anatomy text states “filoplumes are absent in ostriches, emus and cassowaries and are said to be absent in pelicans and anhingas” (Lucas and Stettenheim, 1972). However, there is a significant incidence of filoplumes in ostriches in Australia. This is of particular economic significance to the ostrich industry because filoplumes (and possibly bristle hairs) cause a “pinhole” defect in tanned ostrich hides corresponding to the follicles from which the filoplumes originated. If significant, the affected hide will be considerably devalued and, in some instances, may make the hide worthless.

Morphology In most birds, filoplumes generally occur in association with other feathers – mainly contour feathers – over the body and rarely on bare apteria. A filoplume arises from the skin of a feather follicle or close by. The general description of an avian filoplume is that of a feather that has a slender rachis arising from the edge of its superior umbilicus. The greatest thickness of the rachis is at the tip where a tuft of barbs persists. Barbs are generally absent from the remainder of the rachis (Lucas and Stettenheim, 1972). The function of filoplumes is not fully known but they are believed to serve a proprioceptive function through their location in close proximity to avian lamellar corpuscles (Herbst corpuscles). Filoplumes moult, as do other feathers of the body; the time of which closely parallels that of the feathers with which they are associated (Lucas and Stettenheim, 1972). The most common pattern of filoplume distribution in ostriches is 6-8 filoplumes found in an arc around each main follicle in the crown (back) area of the hide. In severe cases, filoplumes are also found between follicles over the entire quill area. It is not unusual to also find filoplumes in the

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unfeathered (apteric) centre-line of the skin, but filoplumes in this area are not generally detrimental to hide value. Also filoplumes are very common on the skin of the follicle itself, but again this does not lead to a reduction of value of the tanned hide.

Incidence of filoplumes The incidence of filoplumes and reported defects due to pinholes is known to vary between flocks and countries. Estimates of the incidence of filoplumes in ostriches in South Africa are approximately 35% of processed birds (B. Rayner, pers comm.). The incidence of filoplumes in ostriches in Australia, particularly in earlier years has been much higher. Prior to breeder selection efforts of the last 2-3 years, the incidence of filoplumes in Australian breeding birds was variable according to the genetic make-up of the breeding flock. Filoplumes appear to be especially common in ostriches derived from original Australian bloodlines. The incidence of filoplumes has been as high as 40% in predominantly Australian bird flocks or down to less than 5% in flocks derived from predominantly non-Australian bloodlines. As a result of recent culling of filoplume affected breeders, current levels are low and comparable in magnitude to the incidence of filoplumes in South African flocks. Consequently, the contribution of pinhole defects to downgrading of Australian hides has also significantly reduced. It is important to be careful in assessing filoplumes in ostriches less than 12 months of age, as some filoplumes are naturally lost as the bird matures.

3.4 Pinholes “Pinholes” have also been seen in sheep and cattle hides and, in lambskins, the prevalence of these defects is thought to be under a moderate level of genetic control. Pinholes in lambskins are thought to be due to primary and secondary follicles coming out as a “plug” during the fell mongering process (Campbell et al. 1997). True “pinhole” defects in ostriches have been confused with other similar, less uniform defects in ostrich hides (Cooper 2001). Damage due to bacterial degradation or ectoparasite infestation is usually superficial, irregular and rough and not necessarily located in close proximity to a follicle. Filoplume-induced pinholes appear as regular, individual, round, focal indentations usually intimately associated with feather follicles and often in consistent numbers in a crescent pattern around those follicles. Nevertheless, an understanding of the determinants of all ostrich hide defects is desirable ultimately for long term control of hide quality.

3.5 Bristle Hairs Bristle hairs are characterised by a stiff, tapered rachis, thick at the base and tapering to a point. Bristle hairs have no barbs, except at the base during development. They are usually only found around the mouth, nares, ears and eyes of most birds that have bristle hairs (Lucas and Stettenheim, 1972). Like filoplumes, some feathers observed in Australia on ostriches could be classified as bristle hairs. These have not only been found around the eyes and ears of ostriches, but also on the feathered areas of the body. Bristle hairs can have a protective function (to keep foreign bodies out of nostrils and ears) or a tactile function.

3.6 Genetics Over recent years there has been an increasing amount of research into genetic selection and heritability of certain traits in ostriches (Bunter, 2002 and Cloete et al., 1998ab). However, the heritability of filoplumes has not been reported for ostriches. The significant reduction in pinhole affected hides after recent heavy culling of filoplume-affected breeder birds in the Australian population provides preliminary anecdotal support for a genetic relationship to exist. It has also been observed that certain bloodlines of ostriches in South Africa have a predilection for filoplumes (Burger, pers comm.). Filoplumes and bristle hairs do, in fact, occur in ostriches and are considered an

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undesirable trait leading to a defect in tanned ostrich hides referred to as “pinholes”. This defect has enormous commercial significance as pinhole affected hides are worth considerably less value than hides without this defect. The problem has had major economic significance for the Australian ostrich industry, in particular, in the period 2000-2005.

3.7 Economic Implications A study by van Zyl (1998) in South Africa demonstrated that the following four factors had the greatest affect on profitability; 1) income/slaughtered bird (10% increase results in a 55% increase in profit); 2) mortality (10% increase in mortality results in a 35% reduction in profit); 3) eggs/hen and hatchability (10% increase results in a 31% increase in profit) and 4) feed cost (10% increase results in a 27% reduction in profit). In this study, other factors such as the costs of labour and drugs/vaccines/parasiticides had significantly less impact on profitability compared to the four factors listed above. The magnitude and ranking of these factors vary from farm to farm and from country to country. However, it is clear that factors such as the income/slaughter bird can have a major impact on profitability. Currently, in Australia, the income per slaughtered bird is almost entirely based on the returns from saleable meat yield and hide. Although, there is a significant potential additional value in feathers, fat and offal, this value is yet to be realised in Australia. More than 60% of potential return to ostrich producers from processing is from the hide. Although good returns are potentially available for high quality grade A and B hides, returns on

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4. Materials and Methods 4.1 Filoplume and Bristle Hair Study Farms Data for the filoplume study was collected from three ostrich farms (identified as A, B and C) in Victoria, Australia.

Scoring of filoplumes and bristle hairs The farmers who provided the data had various combinations of pairs, trios and colony breeders. The data collected identified the breeding group of the individual progeny but full details on the identity of dams and sires within the pair, trio or colony group could not be obtained. The progeny which hatched from the various breeding groups were scored for filoplumes and bristle hairs prior to slaughter.

Filoplumes and Bristle Hair Score Guide On farm A, progeny were scored for filoplumes and/or bristle hairs on the raised skin attached directly to the feather shaft at the wing site over 3 breeding seasons. The number of birds assessed over each breeding season for which valid data could be assessed was about 300. The breeding groups assessed on farm A were a pure Black strain, 3 Blue x Black crossbreed strains, a Black x Blue crossbreed and a multiple backcross to both Black and Blue strains. For the other 2 farms (B&C) filoplumes and/or bristle hairs were scored at both the wing and hip site for only one breeding season. The number of birds assessed on farm B&C was about 200. The breeding groups on farm B were a pure bred Australian strain, Black x Australian cross, pure bred Black strain, a Black x Blue cross, a Blue x Red cross, a Red x Black cross and a pure bred Red strain. The breeding groups on farm C were a pure bred Australian stain, Australian x Red x Black cross, a pure black cross breed, a Black x Red x Australian cross and a Red x Black cross. On farms B&C scoring consisted of visually assessing the extent of filoplumes and/or bristle hairs for three separate skin areas around the feather shafts. These 3 areas were as follows; 1. The raised skin attached directly to the feather shaft. 2. The area immediately around the feather shaft. This area is approximately 1-2 cm diameter around the base of each feather depending on bird age. 3. The flat area between adjacent feathers. Filoplumes and hairs were scored according to a 4-point scale. Scoring took into account an overall assessment of the immediate surface of the bird near the wing (20 cm x 20 cm) and a similar area on the side of bird over the hip area for all farms except farm A. Scoring was aimed to give a representative score at that site on the bird.

Scoring for filoplumes was as follows; Score 0 Score 1

absence of filoplumes presence of 1 filoplume

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Score 2 Score 3

presence of 2-4 filoplumes presence of more than 4 filoplumes

Scoring for Hairs was as follows; Score 0 Score 1 Score 2 Score 3

absence of hair presence of 1 hair presence of 2-4 hairs presence of more than 4 hairs

Statistical Analyses The analysis of the filoplume and bristle hair data for the progeny of various breeds were assessed with ANOVA in Systat software (Wilkinson, 1996). Bonferroni’s post hoc was used to separate means only if significant main effects were detected by analysis of variance. Bonferroni’s post hoc test is a multiple comparison test based on Student’s t statistic and adjusts the observed significance level when multiple comparisons are made. For farm A the analysis consisted of ANOVA which examined breed, season and the interaction between breed and season.

4.2 Declawing Study Animal Ethics The animal ethics committees of the Department of Primary Industries, South Australia and the University of Adelaide gave approvals for these studies.

Rationale The rationale for the declawing study was to examine short and long-term effects of declawing on the behaviour of ostriches. The first observations were made on ostrich chicks over the first 8 h after the operation. The next assessment of birds was at 1-2 weeks-of-age when the declawing wound was healing and the birds had been transferred from the brooder box to the rearing pens. The final assessment of behaviour was made when birds were about 12 months-of-age when any long-term effects of declawing on behaviour and skin quality would be obvious.

Location The declawing study was carried out at Hazelwood Ostriches; a commercial ostrich farm situated 10 km west of the township of Morwell, which is 100 km south east of Melbourne in Victoria, Australia.

Ostriches One group of ostriches was declawed on the day of hatch in November 2001, by removing the distal phalangeal joint using a Lyon beak-trimming machine (O’Malley, 1997; Glatz, 2001). Another group of ostriches were not declawed. Birds were brooded and reared apart during the trial.

Day old chicks At hatch 50 chicks were declawed while 50 chicks were retained as a control group (not declawed). The chicks were placed in brooder boxes. Behaviour of 10 ostrich declawed chicks in one brooder box and 10 control chicks (not declawed) in another was recorded on videotape for 12h (2000h-0800) after the operation. A camera was suspended above the brooder boxes. An infrared heat lamp over the brooder boxes (l x b x w = 1.5 x 0.75 x 0.4 m) maintained temperature for birds at 28-300C. Each bird was monitored for bouts (engaged in activity for 5 seconds or more) of walking, sitting, standing,

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stepping on other birds, being stepped on by other birds, eating, drinking, self preening, preening other birds and incidence of pecking at the environment, pecking other birds, being pecked by other birds, kantelling and threatening other birds. A bout was recorded when the ostrich chick sustained the activity for 5 seconds or more.

One-two week old chicks At 7 days-of-age the chicks were transferred from the brooder boxes to rearing pens located in a rearing shed. There were ten rearing pens each comprising a brooding area (length x breadth = 1.2 x 5 m) indoors and an outdoor run (1.2 m x 6 m). The brooder area had a concrete floor, covered by a gabba turf mat with an overhead heating lamp. Birds were fed daily in the morning and confined inside for the first 2-3 days and then allowed daytime access to the outside run. Behaviour of week old chicks was recorded on video tape for 8h (0900-1700h) both within the shed and in the outdoor run for each of 5 replicates of 10 birds. Five birds were monitored in each pen using the focal animal methodology described by Lehner (1996).

Year-old birds At 6 months of age 20 declawed birds were allocated to a paddock 100m x 60m, while the control group (not declawed) was placed in an adjoining paddock of the same dimensions. The birds had access to a grass pasture in the paddocks in addition to being provided commercial pelleted feed. Both groups of birds had visual contact with each other. Physical contact between the groups was limited by a 2 m passage between the paddocks. No shelter was available. The birds were provided with a commercial feed usually between 08:00 and 10:00. Approximately 2 kg of food was available to each bird from one feeder. Drinking water was also available from a single drinker in each paddock. Prior to the filming of the yearling birds a four wheel drive vehicle with a canvas canopy installed on the roof rack was set up in an adjacent paddock to provide a good vantage point to film the ostriches in both paddocks. Ostriches were given 3 days to adjust to the presence of the four-wheel drive and presence of the film crew. A camera were mounted on the scaffold and linked to video recorders. The camera operator stood on roof rack and tracked an individual ostrich during each filming session. Thirty minute video records of 20 individual ostriches were made for each treatment. An individual declawed bird was filmed in one paddock. When completed a control bird was tracked in the other paddock as the comparison.

Behaviours For each ostrich, behaviours were monitored from the videotapes. A bout was recorded when the bird engaged in the activity for 5 seconds or more. The following inactive, ingestive, posture changes, grooming, aggressive and locomotory behaviours were recorded on each ostrich. Inactive Sit down: Sitting with legs folded under the body Stand: Standing with head raised Ingestive Forage: Pecking at the ground and vegetation while standing, walking, sitting up or sitting down. The head may be raised for less than 5 seconds. Eat: Eating diets as supplied in food bins or immediate area where the diet was scattered. The head may be raised for less than 5 seconds. Drink: Drinking from water trough. The head may be raised for less than 5 seconds.

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Eliminate: Excretion of faecal and urinary waste 4.2.8.3 Change Position Step: Any change in position taking less than 5 seconds that occurred while the bird was standing. Shift sit: A shift in position while sitting in either position. Stand up: Standing up from either sitting position. 4.2.8.4 Grooming and other behaviours Preen: Using the beak to preen feathers on any part of its body. Preen others: Using the beak to preen feathers of other birds Head scratch: Using one of its feet to scratch its head. Headshake: Shaking its head while walking, standing or in either sitting position. Stretch: Stretching the body and neck, usually followed by a body shake. Excludes defensive or offensive stretching. Exhibition: Walking or standing with neck feathers flared out. Fence Peck: Pecking at the fence wire or post. Head through fence: Poking the head through the fence while standing or pacing. Kantelling: Twirling and rocking from side to side 4.2.8.5 Aggressive behaviours Run chase: Running at another bird. Run away: Running from another bird. Give thrusts: Any action that threatens another bird, including run chase. Receive thrusts: Any threatening action that the bird receives, including those that make it run away. Peck: When the bird pecks at another bird. Pecked: When another bird pecks the bird. Step push: Any change in position from a standing position resulting from a push by another bird. Threats: When the bird stands erect with feathers raised and wings held away from the body.

Locomotory Search: Walking through paddock (other than area within 1.5 m of the fence) with head lowered. Search pace: Walking parallel to, and within 1.5 m of the fence with head lowered. Walk: Walking through enclosure (other than area within 1.5 m of the fence) with head raised. Pace: Walking parallel to, and within 1.5 m of the fence with head raised. Run: Running through enclosure (other than area within 1.5 m of the fence). Run pace: Running parallel to, and within 1.5 m of the fence. Slip: Bird slipping on ground and falling over Bumping: Birds running into each other accidentally

4.3 Skin Quality of Declawed Birds Location The assessment of the skin quality of declawed versus control birds were undertaken on a commercial ostrich farm located near Winchelsea in Victoria, Australia.

Declawing 400 birds were declawed on the day of hatch by removing the distal phalangeal joint using a Lyon beak-trimming machine (O’Malley, 1997; Glatz, 2001). Another group of 300 ostriches were not declawed.

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Birds Birds were maintained on starter, grower and finisher diets and reared apart throughout the trial. The birds were initially maintained in groups of 100 up to six weeks of age and thereafter maintained in groups of 50 birds in feed lot paddocks (30 m x 70 m) with 7 m high fences. The paddocks contained no forage. Water was available ad libitum.

Transport A commercial ostrich transport company transported the birds to Mytrleford abattoir.

Minimum grading standard of ostrich skins Skin quality of declawed birds were compared to a control group of birds and graded according to Industry standards. A defect can be a hole, a scratch, a loose scab, a healed wound or bacterial damage. The crown is the area with quills, except in the neck, down to wing fold and also the stomach quill area. For grading purposes the crown is divided into four quarters. The lines dividing the crown area into the 4 quarters are 25 mm wide. The vertical line stretches from the base of neck to the bottom of crown and the horizontal line stretches between the widest quills on either side of crown area. First grade A defect in one of the quarters as long as it is not larger than approximately 40 mm x 40 mm. At least three quarters must be free from defects. Defects on the cutting lines do not affect the grade. A few less visible scars are allowed as long as they are outside the crown area. Second grade A skin with defects affecting two quarters. At least half the skin must be free from defects. Visible defects outside the crown area are allowed and will not affect the grading. Third grade At least one quarter of the skin must be free from defects. Visible defects outside the crown area are allowed. Fourth grade At least one quarter of the skin must be free from defects. Extensive visible defects outside the crown area are allowed and will not affect grading.

4.4 Statistical Analysis of behaviour and skin grades Base SAS software (SAS Institute, 1988) was used to analyse the behavioural data. Analysis of variance by GLM procedure was used to determine the significance of the main effects (declawing, stress and temperature) and interactions on locomotor, exploratory, inactive, social, ingestive and aggressive behaviours. Duncan’s multiple range tests was used to separate means when significant main effects were detected by the analysis of variance.

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5. Results and Discussion 5.1 Filoplume/Bristle Hair Study Incidence of filoplumes There was a range in incidence of bristle hairs (across farms) from 20-80% and 40-52% for filoplumes. High levels (score of 3) of bristle hairs and filoplumes were noted in approximately 15% and 5% of the progeny respectively. Farm A On farm A there was no significant (P>0.05) differences noted for the various breeding groups over the 3 seasons for filoplume score and bristle hair score (Tables 1 & 2). In addition there no significant interaction between breeding groups and season. However a differences between the breeding groups for year approached significance (P=0.06) on farm A for filoplume score. The results in Table 1 show that the filoplume scores for year 2 were higher for most of the breeding groups compared to years 1 and 3. With this result being close to significance it is worth considering some of the reasons why this may be occurring. The function of filoplumes is not fully known but they are believed to have a proprioceptive function through their location in close proximity to avian lamellar corpuscles (Herbst corpuscles). The role of the filoplume may be to assist with control of the orientation of the follicles and hence feather position. This may be important for maintaining thermoregulation. In second year of the trial on farm A a colder winter was experienced. The increase in filoplumes may have been due to a greater need in the bird to control feather position for maintaining thermal control. Alternatively genetic variability may have resulted in changes in the incidence of filoplumes in year 2. Farm B On farm B where a more comprehensive scoring assessment was used, there was a significant difference noted between the breeding groups for filoplumes on both the wing and the hip and for bristle hairs on the hip (Table 3). In addition the incidence of filoplumes between the breeding groups was significantly (P