Mycoplasma gallisepticum Outbreak in a Smallholder Broiler Flock By Kate Backel The Importance of Prevention, Recognition and Treatment of Disease in Backyard Poultry Ernest Goh @ www.ernestgoh.com Going to talk about MG in a small holder broiler flock – then use that as an example to illustrate the importance of disease recognition, prevention and treatment in backyard poultry. – 1 Small broilers farm: Cornish Crosses Recently expanded production from a few 100 to 3000 Ages: 4, 6, 8 weeks Plan: 3 age groups always on farm Group always available for slaughter/shipment Youngest birds kept enclosed, moved to mobile pasture pens between 5-8 weeks of age On-site slaughter Shipped to farmers markets and high end restaurants for value added as free range poultry HISTORY: 1 week of increased mortality and respiratory signs The case: So the flock we are dealing with consists of: approximately 3000 Cornish cross broilers, at 4, 6 and 8 weeks of age The farm had recently expanded production from a few hundred up to several thousand The youngest birds were kept enclosed in the barn and were then moved to mobile pasture pens between 5-8 weeks of age Birds were slaughtered on site and shipped to farmers markets and high end restaurants for value added as free range poultry 2 Pastured broilers Housed next to open layer aviary Ducks, pigeons, sheep and goats that were all kept in close proximity Open facilities. Many free-ranging animals. Called AHDC poultry extension services after a week of noticing swollen eyes, Gurgley/raspy breathing and increased mortality History and The Farm Photo credit: Dr. Jarra Jagne We went out to the farm to take a look In the back of the photo, is where the broilers were kept. This set up is typical for pastured poultry and is made up of a fenced in area that contains a covered shelter to protect the birds from the elements. Many other animals kept on the farm including: Pigeons, Ducks, Cows and goats (that are not in this picture) 3 Photo credit: Dr. Jarra Jagne Additionally, this farm raised laying hens that were housed in a large outdoor aviary that was located only about 400 yards from the broiler flocks As you can see, the fencing did a poor job preventing the layers from escaping and they were often wandering around the farm. 4 This is the youngest group of the affected broilers: Looking around this photo, you may notice that many birds appear lethargic, some are hunched in corners with ruffled feathers On close inspection the bedding is wet and soiled and the feed and water dishes are full of that same soiled material Additionally, what you can’t see is the other side of this picture is actually open to the farm, allowing the free chickens and other farm animals access to this area. In fact – in the back there is one of the laying hens just hanging around in here 5 Underweight Periocular swelling – manual expression of caseous exudate from infraorbital sinus Stertorous respiratory noise and occasional coughing Physical examination: Photo credit: Dr. Jarra Jagne Physical examination revealed: 6 Severe acute fibrinosuppurative sinusitis, bronchitis, airsacculitis Moderate acute fibrinosuppurative peritonitis, perihepatitis Field Necropsy: Photo credit: Dr. Jarra Jagne Following the physical examination we also performed a field necropsy on several of the ill birds … - Picture here shows the trachea and bronchi on cut section and there is a large amount of white caseous material in the main stem bronchi 7 BROILERS: Increase mortality Lethargy Decreased weight gain Sinusitis Conjunctivitis , eyelid edema Increased respiratory effort Necropsy: Airsacculitis and peritonitis Problem list: FARM: Poorly constructed indoor housing Lack of separation between different age groups Access of other animals to the broilers Close proximity to the processing facility Poor sanitation Lack of a clean water source Our problem list consists of: We also identified some general farm problems including: 8 Mycoplasma gallisepticum Fowl Cholera (Pasteurella multocida) Infectious Coryza (Avibacterium paragallinarum) Newcastle Disease Avian Influenza Mycoplasma synoviae Infectious Bronchitis Aspergillosis Chlamydiosis Differentials: Our main differentials were ….. three bacterial infections that can produce similar clinical signs including conjuctival, sinus and pharyngeal inflammation. It is also important to rule out are avian influenza and exotic Newcastle Disease which are reportable disease and have important public health implications 9 Diagnostics: Mycoplasma gallisepticum agglutination: All broiler and layer samples positive Tissue Mycoplasma culture Aerobic culture Lung Many Pasteurella gallinarum, Escherichia coli Eye Many Pasteurella gallinarum Air Sacs Many No growth To differentiate between the possible bacterial diseases, samples of tissue collected during necropsy were submitted for mycoplasma and aerobic bacterial culture. The results were positive across the board for mycoplasma. Additionally samples were found to be positive for opportunistic bacteria. Mycoplasma agglutination was also submitted on blood drawn from the broilers, as well as the layers and all samples came back with positive results. 10 Mycoplasma gallisepticum Secondary Escherichia coli and Pasteurella gallinarum Diagnosis: Prognosis: Severe disease in turkeys and young broilers Worse in cases complicated by secondary infections Up to 30% mortality Losses from decreased weight gain, downgrading of carcasses and carcass condemnation Layers: mild disease and decreased egg production Thus, we confirmed this flock was affected by MG, in addition to secondary bacterial infections… MG can produce severe disease in turkeys and young broilers… It is likely that the broilers as well as the layers were affected on this farm, but the relatively mild signs in the layers went unnoticed. 11 Slaughter and process 6 and 8 week old chickens immediately Treat 4 week olds with 3 days of Tylosin added to drinking water (Withdrawal: 1 day meat, 0 days eggs) Farmer was advised to improve housing infrastructure for birds before scaling up production Case lost to follow up. Treatment Plan & Outcome: Our treatment plan for this flock was to attempt to salvage the remaining chickens by sending the oldest to slaughter and treating the youngest. 12 Cost: Test Cost per test Total Mycoplasma culture $27.00 X4 $108.00 Aerobic bacterial culture $38.00 X4 $152.00 MG Agglutination $3.75 x20 $75.00 TOTAL: $335.00 13 Backyard poultry: www.poultryone.com/raisingchickens ** Before I segue into talking about backyard flocks, I just want you to keep in mind the problems identified on this particular farm, and how they reflect a lack of biosecurity planning and poor preventative health measures in the face of a recent increase in flock size 14 Mainly chickens, fewer turkeys, waterfowl and other poultry Families, small business owners, co-ops Urban, suburban and rural neighborhoods 90% of the backyard flocks surveyed (defined as less than 1000 birds) had fewer than 100 birds Urban Flocks the smallest Denver, Los Angeles and Miami averaged 5, 11, and 19 respectively Who/What/Where: https://notionscapital.wordpress.com/category/poultry/ Backyard poultry most commonly consists of chickens but people may also choose to keep turkeys, waterfowl or other species such as guinea fowl Flocks are owned by families, small business owners, or often co-ops in urban areas They may be found anywhere including cities, residential neighborhoods or rural areas Most flocks are small – one study showed that 90% of flocks surveyed had less than 100 birds With Urban flocks typically being the smallest. For the purpose of presentation, I defined backyard flocks to include chickens kept solely as pets to small enterprise flocks with up to 3,000 birds. The definition was kept broad to include amateur poultry farmers whose goals were to sell free-ranging poultry in support of the local food movement. Often these small businesses develop from owners who may have started out with just a few dozen birds and began to expand as the demand for free-range chicken grew. 15 Local food movement: source of eggs & meat Enjoyment, human-animal bond Community involvement Economic benefits (from product sales) Food security Improved nutrition Environmental health Other: fertilizer, pest control Backyard poultry; why? http://sierraclub.typepad.com/greenlife/2008/10/ready-for-an-ev.html So why do people choose to keep poultry? I’ve listed a bunch of reasons here, but the top three listed here are probably the most important reasons .. First of all, many people are keeping chickens for household consumption of eggs and meat. As the commercial poultry sector moves to larger and larger farms more removed from the public eye, consumers are interested in regaining their personal control of food choices and often own chickens in support of the local food movement Second, many people are choosing to keep chickens for their own enjoyment – they serve as companions, entertainment and educational tools for children Lastly, an important reason to promote poultry ownership is because it encourages community involvement. Various studies have shown that urban agriculture can improve social connections, civil engagement and help build a sense of community - The other reasons listed here are motives for people to be interested in poultry, but are not as well substantiated 16 Food borne illness Disease emergence Others: Lowered property values Noise Odor Increased pest Humane treatment Risks: http://homegrown.org/ Unfortunately, there are some risks involved with keeping back yard chickens –I will discuss the first two more in depth… the other risks listed here practical concerns linked to urban poultry and can be mitigated through city codes such as imposing a maximum chicken limit and not allowing roosters, etc… 17 Nontyphoidal Salmonella Campylobacter jejuni Escherichia coli Listeria monocytogenes Risks: Food Borne Illness Disease prevention in commercial flocks : USDA: Poultry Products Inspection Act and Egg Products Inspection Act Regulate sale, transport and slaughter of chickens and egg products Backyard flocks exempt from same federal regulations Processing/handling of backyard poultry products not well regulated. The first risk to consider is that of food-borne illness. Some of the most common foodborne bacterial diseases (listed in the box here) are closely linked to poultry products. And as mentioned previously, many people are choosing to keep backyard poultry as sources of eggs and meat for either household consumption or local sale. Unfortunately, many people are not aware of the risk of foodborne illness. Commercial facilities are federally regulated through the Poultry Products Inspection Act and Egg Products Inspection Act. Facilities processing over 20,000 birds are year are required by the USDA to have continuous bird-by-bird inspection and operate under up-to-date HACCP plans. Conversely, backyard flocks are exempt from these stringent regulations and do not always have the resources to invest in these plans, or take appropriate steps to reduce food safety risks. 18 “A microbiological comparison of poultry products obtained from farmers’ markets and supermarkets in Pennsylvania” 2013. Risks: Food Borne Illness Farm type Salmonella Campylobacter Farmers market 28% (28/100) 90% (90/100) Conventional 8.0% (4/50) 52% (26/50) Organic 20% (10/50) 28% (14/50) To support the hypothesis that meat products from backyard flocks might carry a higher contaminant load than those from conventional flocks, a study out of Pennsylvania in 2013 examined the difference in bacterial loads on farmers market meat vs. supermarket meat. All farmers market meat was from vendors who sold poultry that were either raised or processed by the vendor or other noncommercial poultry farmer. What they found was a significantly higher proportion of farmers market meat cultured positive for Salmonella and Campylobacter than conventional meat. Additionally, the amount of campylobacter on positive products was considerably higher than the supermarket meat. The results from this study demonstrate there is a risk associated with backyard chicken products and underlines the need to develop food safety training for small enterprise farmers 19 Backyard flock reports: 10 laboratories – 623 and 1066 diagnosed submissions in 2012 and 2013 respectively Results: Bacterial diseases most common (notably E. coli and Mycoplasma gallisepticum) Internal Parasites Viral disease: Marek’s disease USDA: APHIS NAHMS 2004 poultry survey: 13.4 % of respondents experienced disease in the previous 12 months 2.4 % of respondents sought veterinary attention 2.8 % vaccinated Risks: Disease emergence/spread The second important risk to discuss is the potential for disease emergence from backyard flocks and the possible threats it might pose to the commercial poultry industry and public health. To get a handle on the types of disease being seen in backyard poultry, in 2012 and 2013 10 laboratories from different states put together a list of the most commonly diagnosed diseases in privately owner poultry that was submitted to the labs. They found…… *Importantly, many of these diseases are controlled in the commercial industry through biosecurity and appropriate management, other diseases such as Marek’s disease which have been more of less eliminated from our commercial flocks due to the use of vaccines are popping back up in backyard flocks. To make these statistics more impactful, a 2004 USDA: APHIS survey, reported while over 13 percent of responded experienced disease in their flocks, only 2.4 percent sought veterinary attention. So it is likely that these results do not represent the true prevalence of disease in backyard flocks. 20 Mycoplasma gallisepticum: Decreased significantly in commercial industry due to NPIP Identified in Finches and Songbirds in 1994 Documented to spread from finches to chickens in 1998 Finch strain identified in commercial turkey flock in 2003 2/3’s of backyard flocks reported contact with wild birds Risks: Disease emergence/spread Thepoultrysite.com Poultryone.com http://columbusoh.wbu.com/ One example of disease emergence and spread is that of MG (as see in the broiler flock described in the case). For the past 50 years, MG has been controlled in the commercial sector by elimination of the disease in primary breeder flocks (and preventing vertical transmission) However, in 1994 an outbreak of MG was identified in wild bird populations and now, the disease now seems to be re-appearing in backyard flocks. Because many backyard flocks are constantly exposed to wild birds; backyard poultry are both susceptible and may serve as source of infection for commercial flocks. 21 High Pathogenic Avian Influenza (HPAI) – H5N1 Parts of Asia, Africa, Middle East and Europe Since 2004 has caused 429 deaths out of 784 cases Economic losses estimated in the billions Risks: Disease emergence/spread Another example that we can’t ignore, is the potential for an outbreak of Avian Influenza. The emergence H5N1 High pathogenic avian influenza in Asia, Africa, Middle East and Europe have resulted in the deaths of 429 out of 784 infected people since 2004 and economic losses are estimated to be run into the billions. These outbreaks been linked to exposure of urban and outdoor flocks to wild birds (especially waterfowl) that are known to carry the disease. Additionally, it is important to point out that illness in humans has only occurred in those in close contact with sick or dead birds. 22 1997-2005: 16 outbreaks of LPAI and 1 of HPAI Recent outbreaks in the United States of H5N2, H5N8 and H5N1(new) Identified first in wild birds in November in B.C. following Pacific, Central, and Mississippi flyways HPAI in the United States: So far: 6 commercial premises depopulated (372,450 birds) 9 backyard flocks http://www.aphis.usda.gov/wps/portal/aphis/ourfocus/animalhealth Up until very recently the United States had experienced only very few outbreaks of Avian Influenza. Between 1997 and 2005, there were 16 outbreaks of low pathogenic avian influenza A viruses (H5 and H7 subtype) and one outbreak of highly pathogenic avian influenza A (H5N2) in poultry. However, this past December marked the beginning of a stream of cases in the Western and Midwestern US. New mixed-origin viruses (H5N2, H5N8 and H5N1) have been identified in many wild birds, backyard and commercial flocks. This image shows the distribution of cases in the United States since December. Current epidemiologic evidence suggests outbreaks have been due point-source introductions from movements of wild birds along migratory paths. 23 1997-2005: 16 outbreaks of LPAI and 1 of HPAI Recent outbreaks in the United States of H5N2, H5N8 and H5N1(new) Identified first in wild birds in November in B.C. following Pacific, Central, and Mississippi flyways HPAI in the United States: So far: 6 commercial premises depopulated (372,450 birds) 9 backyard flocks http://www.pacificflyway.gov/About.asp If you compare this map of the Flyways in the United States to the last map of distribution of cases, you can see they follow a very similar pattern. 24 High pathogenic avian influenza outbreak since December Recent outbreaks of HPAI in the U.S. http://www.aphis.usda.gov/wps/portal/aphis/ourfocus/animalhealth Here is the most recently updated table listing the confirmed outbreaks in backyard and commercial poultry since December 19th, with the most recent confirmed only 4 days ago. Many of these have been in backyard flocks. As highlighted by the red boxes To control the spread, state officials are working closely with the USDA to identify and depopulate infected flocks through incineration/burial. Much of this is dependent on identification and reporting of disease events. The USDA relies on backyard enthusiasts to continue to practice good biosecurity, prevent contact between their birds and wild birds, and to report sick birds or unusual deaths to State/Federal officials. So far 6 commercial premises and 9 backyard flocks have depopulated. 25 Supporting backyard poultry; Ameliorating risk Cooperation of public health officials, health care providers, veterinarians, and backyard flock owners Open channels communication with chicken owners Improve regulations Food safety education Provide information about poultry health and disease   Keep your distance Keep it clean Don't haul disease home Don't borrow disease from your neighbor Know the warning signs of infectious bird diseases Report sick birds: Despite the risks that were identified; disease recognition, prevention and control can help ameliorate or eliminate these risks. The recent cases of Avian influenza provide a good example of a disease that threatens both the commercial and backyard poultry sector. Additionally, these instances highlight the importance for cooperation of backyard poultry owners in helping to identify disease. By continuing to work together, there is a greater likelihood that we will be able to control these outbreaks and ensure the safety of our poultry. Instead of polarizing backyard flocks owners and commercial industries, these groups need to work together to identify and eliminate disease risks. Educating the backyard audience will help ensure the continued success backyard flocks and the safety of poultry products. Ways that we can do this is through the cooperation… Recently, the USDA came out with a campaign to encourage backyard flock owners to improve biosecurity measures for their birds. The website provides simple guidelines poultry owners can follow to help protect their birds. * Additionally the website also provide a number of resources for flock owners about appropriate care and management of poultry. . 26 Play an active role Get to know your basic poultry diseases Know what you can and cannot prescribe (legally) Be familiar with the nearest diagnostic lab/poultry veterinarian *Seek advice Know where to direct clients for appropriate resources Supporting backyard poultry; The veterinarians role www.cdc.gov Lastly, it is important that veterinarians get involved. As the backyard poultry movement continues to grow, there is a greater and greater chance that you will see a chicken or a duck in your small animal practice. With that in mind, as the veterinarian, you should play an active role… BY working together we can help ensure the continued survival and success of backyard flocks and guarantee that the public is able to continue experiencing the joys of owning chickens and other poultry. Important resources: Biosecurity for birds – USDA website State poultry veterinarian Local university extension offices Good websites – PennState extension For local codes/permitting: contact state regulatory body/local governing body – NY department of Ag Publications: Storey's Guide to Raising Chickens and the Chicken Health Handbook by Gail Damerow Backyardchickens.com *be careful because there are a lot of amateurs on this site, so may need to refer to elsewhere 27 Jagne J. and Lichtenwalner A. Backyard & Small Commercial Flocks Disease Report. 2012 and 2013. Report of the Committee on Transmissible Diseases of Poultry and other Avian Species. Preprint. L. Garber, G. Hill, J. Rodriguez, G. Gregory, L. Voelker. 2007. Non-commercial poultry industries: surveys of backyard and gamefowl breeder flocks in the United States. Prev. Vet. Med., 80:120–128. Beam A., Garber L., Sakugawa J., and Kopral C. 2013. Salmonella awareness and related management practices in U.S. urban backyard chicken flocks. Prev. Vet. Med., 110(3-4):481-8 Garber L., Forde-Folle K., Beam A. and Hill G. 2009. Survey of small-enterprise chicken operations in the United States. Prev. Vet. Med., 90:204–210. Reference of Health and Management of Backyard/Small Production Flocks and Gamefowl Breeder Flocks in the United States. 2004. USDA:APHIS:VS,CEAH, National Animal Health Monitoring System, Fort Collins, CO Grunkemeyer V. 2011. Zoonoses, Public Health, and the Backyard Poultry Flock. Vet Clin North Am Exot Anim Prac. 14(3):477-90. Scheinberg J., Doores S. and Cutter CN. 2013. A microbiological comparison of poultry products obtained from farmers’ markets and supermarkets in Pennsylvania. J Food Saf. 33:259–264. Bouvier, JM. 2012. Illegal Fowl: A Survey of Municipal Laws Relating to Backyard Poultry and a Model Ordinance for Regulating City Chickens. Environmental Law Reporter: News & Analysis. 42 (9). Selected references: Dr. Jarra Jagne Thank you Dr. Beth Buckles My Advisors: Special thanks to: Dr. Alex Travis Dr. Beth Bunting Jennifer Peaslee My parents My boyfriend And the class of 2015 Ernest Goh @ www.ernestgoh.com Influenza – influenza A virus – many different serotypes based on presence of surface glycoproteins neuraminidase or hemagglutinin. There are 9 neuraminidase proteins and 16 hemagglutinin Rapid antigenic shifts due to segmented genome – when replicating in the presence of another flu virus can easily reassort Also have large amount of antigenic drift due to absence of proof-reading enzymes Low path vs. high path is determined by ability to produce severe disease in chickens Questions: Have there been any confirmed human cases? – no, CDC currently considers the risk to be low. Avoid contact with sick or dead wild birds. If contact occurs, make sure to wash hands and change clothes Has there been any spread of the disease from flock to flock? – no current thinking is only point source introduction (carried by asymptomatic wildbird), no horizontal spread/propagating. The USDA and state agencies are doing a good job containing the outbreaks Economic impacts – 20% of US meat production is exported -valued at 6.4 billion in 2014 Trade restrictions have been placed on the USA by 11 countries have suspended imports of all US origin poultry and poultry products 35 countries have regionalized the US – only allowing imports for un-affected areas Outbreaks have been: H5N2, H5N8 and H5N1(new) – ALL HIGH PATH – fatal form, known to spread rapidly between flocks H5N8 from Asia – through pacific flyway and mixed with north American versions H5N2 virus and new H5N1 virus also identified. H5N1 – is NOT the same virus that caused human illness Typically waterfowl known to carry less infectious strains of the disease Low path strains are capable of mutating to high path under field conditions Recommend to poultry owners: always wash hands after handling chickens, keep chickens out of the house, be extra cautious with young children or elderly. To decrease risk of food borne illness – always handle poultry products properly: Maintain work areas clean of raw chicken and scraps, Poultry should be cooked to an internal temperature of 165 ˚F kills bacteria and viruses VACCINATIONS for backyard flocks? – You can buy large quantities – typically fairly inexpensive for “pet” owners – (for Mareks disease - 1000 dose vial for $20) – only good for 2 hours after opening, some are difficult to keep in flock owners homes (require liquid nitrogen) Control of internal parasites: good management – good sanitation, rotate ranges, avoid mixing ages/species. Piperazine, levamisole, thiabendazole (Withdrawal period usually about 1 week) *coccidiosis – (eimeria) – management, drugs (amprolium – no withdrawal, sulfas- 5 days or 10 days withdrawal), sanitation Control of external parasites: lice – powdered insecticide (repeat in 7 days), pyrethrum, ivermectin (can be toxic) Resources: Biosecurity for birds – USDA website, State poultry veterinarians, Local university extension offices (Good websites – PennState extension) For local codes/permitting: contact state regulatory body/local governing body – NY department of Ag Publications: Storey's Guide to Raising Chickens and the Chicken Health Handbook by Gail Damerow. Cheryl B. Greenacre, Teresa Y. Morishita - Backyard Poultry Medicine And Surgery For Vets *THEPOULTRYSITE disease guide Backyardchickens.com *be careful because there are a lot of amateurs on this site, so may need to refer to elsewhere 29