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| PROJECT No | PROJECT TITLE | RESEARCHER | PHONE | ORGANISATION |
| ADH-1A | Marketing options of deer horn and deer co-products for the Korean and Chinese markets | Mr. David Walker | (03) 5674 5520 | Australian Deer Horn & Co-products Pty Ltd |
| ADH-2A | Microbial Flora of Velvet: A Pilot Study | Dr. Jeff Fyffe | (03) 5442 5455 | Australian Deer Horn and Co-products Ltd |
| DAV-100A | Maintaining year-round production of quality venison: the use of "immunocastration" vaccines to control "rutting" behaviour | Dr. Julie Simons | 03 9217 4200. | Victorian Institute of Animal Science |
Maintaining year round production of quality venison: The use of immunocastration vaccines to control "rutting behaviour.
Objectives
Production of a "year-round" supply of quality venison has been recognised by the Australian deer industry as being vital for expansion in export and domestic markets. Rutting behaviour in stags however has limited the supply of venison during the breeding season due to weight loss, injury decreasing the value of the carcass and aggressive behaviour making the stags very difficult to control, handle or transport. The cause of this aggressive behaviour is the influence of testosterone as the testes become active during the rut. Immunocastration offers a possible alternative. Vaccination against LHRH has been shown to temporarily control testicular function and all related sexual behaviour. This process will allow stags to grow as entires but behave as castrates in the targeted breeding season. The result is easy yarding and transporting due to the lack of aggressive behaviour and that the weight loss associated with stags in the breeding season should be significantly reduced.
Research
The project was defined within four major experiments:
An immunocastration vaccine was developed using a formulation seen as being most optimal for use in deer. This vaccine and another vaccine supplied by a commercial company have been shown to be effective in reducing testicular function in stags in up to 95% of the herd. Whilst antibody titre is high, rut induced weight loss and aggressive behaviour can be reduced.
Implications
In practice however the vaccine is limited in four ways:
RIRDC Project No: DAV-100A
Researcher: Dr. Julie Simons
Organisation: Victorian Institute of Animal Science, 475 Mickleham Rd, ATTWOOD VIC 3049
Contacts: Phone: 03 9217 4200. Fax: 03 9217 4299. E-mail: simonsj@woody.agvic.gov.au
Marketing options of deer horn and co-products in China & Korea.
Objectives
The Australian Deer Industry is relatively young in terms of established farming enterprises, therefore more hard work must go into production and marketing to access and maintain a profitable market share of the sales for the producer. While New Zealand has built a multi million dollar industry from deer farming and its related sectors they had a large feral population to draw from in the early days and importation of quality breeding stock began many years before deer were farmed in Australia. The Asian ethnic community both here and overseas have a long history of deer product usage.
Research
While in China and Korea in January, 1998, I met with many buyer/processors and discussed the problems with identifying the many different grades depicted on our present product information charts. The discovery that many of these people cannot read English has highlighted our biggest drawback to achieving sales into these countries. The product quality is highly praised.
Outcome
Chinese velvet processors are showing interest in setting up drying plants in Australia, particularly in Melbourne. Samples of velvet and velvet extract have been sent to several of these companies in China for testing.
Implications
The success of a concise Australian Reference Handbook in defining production and harvesting specifications must encourage the Asian buyer/processor to purchase our velvet in the first instance, but also our co-products, as that is where the profit lies.
RIRDC Project No: ADH-1A
Researcher: David H Walker
Organisation: Australian Deer Horn & Co Products Pty Ltd., Tarwin Road, INVERLOCH VIC 3996
Contacts: Phone: (03) 5674 5520 Fax: (03) 5674 5577
Microbial Contamination of Velvet - A Pilot Study
Objective
It has been stated that 99% of all velvet is contaminated with bacteria at the cut end. There was also a suggestion that this contamination extends up the shaft. Velvet is a deer product for human consumption that has been used in Eastern medicine for at least 2000 years. The pharmacologically active components are increasingly being recognised as having application in many areas of human medicine. There is no literature available in the world that records the bacterial flora of the cut end and core of velvet. As a consequence, if the assertion that Australian velvet is contaminated, there is great potential for damage to the velvet industry. Thus it is necessary to obtain an understanding of the microbial flora of velvet.
Research
The project required the development of a new technique to obtain, aseptically, samples from the core of the velvet. The project design called for 20 sticks of "B" Grade velvet, carrying NVAS identification tags, to be selected at random and then examined for microbial presence at the cut end, between the brow and bez tyne, the bez and trez tyne and between the trez tyne and the tip. In all 80 swabs were collected and examined.
One stick that was included came from a consignment that was known to have thawed and refrozen in transit; another stick was found to have an unhealed puncture wound at the sampling site between the bez and trez tynes.
In view of the microbial findings on the stick that had thawed and refrozen, a second experiment was conducted which looked at the extent of migration of bacteria up these sticks.
Results
The results show that except in certain circumstances, the core of velvet antler is sterile, while the cut surface has a resident microbial population composed principally of miscellaneous Gram-negative bacilli and Bacillus cereus group species. This is possibly indicative of the conditions under which the velvet was harvested. The circumstances that led to microbial contamination of the core of the velvet were thawing and refreezing and unhealed puncture wounds.
No Salmonella, Yersinia, Listeria or Escherichia coli were isolated from any site, however in the first experiment a pure growth of a Streptococcus was found at the site of the unhealed puncture wound.
In view of the significance of the B cereus group as potential human pathogens, the second study was designed to examine the possibility of bacterial migration into the core of velvet that was known to have thawed and been re-frozen.
This second experiment found a similar result to the first however there was migration of gram-negative bacilli isolated to at least 7.5cm from the cut end. When contamination was light a surprising finding was almost pure growth of Acinetobacter sp. These bacteria have only twice been recorded in the world literature as being the cause of food spoilage. The full significance of this finding is unknown, however it is known that Acinetobacter sp are a major health issue in intensive care units in hospitals.
Implications
All velvet will have a resident population of normal bacteria at the cut surface. This is unavoidable and not of any concern. The only time that a problem will arise is if the velvet is allowed to thaw and re-freeze at any time or if there are full thickness puncture wounds in the skin of the velvet.
Despite having potentially harmful bacteria resident at the cut surface, they do not cause a problem to the Australian velvet industry even under the most adverse conditions.
It is important, from a Quality Assurance point of view, that no velvet with any skin puncture should be allowed "in grade".
Producers must adhere closely to the NVAS protocol and chill velvet immediately after removal from the animal to adhere more closely to the Quality Control of velvet production.
Producers must keep dust levels to a minimum during harvesting and velvet must remain frozen from the time of harvest to the point of sale. This includes the grading table.
Any velvet with an off-odour must be condemned.
The major conclusion drawn from these studies is that provided velvet is harvested in strict accordance with the NVAS protocol, and grading is of the highest standard, then Australian commercial frozen velvet will have low numbers of normal bacterial flora at the cut surface and will be sterile in the core of the stick.
Contingent upon adherence to these conditions, then Australian velvet harvested under the NVAS protocol can be considered to be of the highest possible product for human consumption. This places Australia at the forefront of Quality Assurance as well as Quality Control of deer velvet production, since this project has never been done anywhere else in the world.
Leading from this pilot study, is the requirement to quantify the extent of cut end "contamination" and the origin of this contamination. Further it is necessary to determine the extent of migration of bacteria into the cut end of normal velvet.
RIRDC Project No: ADH-2A
Researcher: Dr. Jeff Fyffe
Organisation: Australian Deer Horn and Co-products Ltd
Contacts: Phone: (03) 5442 5455 Fax: (03) 5441 5360
