COMPOSTING POULTRY MORTALITIES FROM AN AVIAN INFLUENZA OUTBREAK WESTERN CAPE, SOUTH AFRICA Dr Melanie Jones BVSc

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1 COMPOSTING POULTRY MORTALITIES FROM AN AVIAN INFLUENZA OUTBREAK WESTERN CAPE, SOUTH AFRICA 2017 Dr Melanie Jones BVSc

2 Composting of animal mortalities since 2012 in Cape Town, South Africa dogs and cats from animal welfares, seals, pigs, horses and penguins. Permission granted by Environmental Affairs as a Veterinarian Surgeon composter was overseeing the composting process to ensure sterilisation temperatures in compost heaps. Approached by Department of Agriculture, State Veterinarian to assist with handling carcasses from an outbreak of highly pathogenic avian influenza.

Highly Pathogenic Avian Influenza Outbreak Appeared in Asia in 2014 and spread across Asia and Europe arriving in Egypt in Nov 2016, Zimbabwe in May 2017 and South Africa on 21 June 2017 (first

3 Highly Pathogenic Avian Influenza Outbreak Appeared in Asia in 2014 and spread across Asia and Europe arriving in Egypt in Nov 2016, Zimbabwe in May 2017 and South Africa on 21 June 2017 (first commercial poultry farm in South Africa) 21 August 2017 Ostriches in Western Cape 23 August 2017 first commercial poultry farm in Western Cape Symptoms, Nasal discharge, swollen wattle and comb, haemorrhage and rapid death in poultry and wild birds.

4 Locations of first confirmed cases

5 Western Cape location of poultry and ostrich farms

6 Outbreak in Ostriches First birds in the Western Cape to test positive for avian influenza was in commercial ostriches All positive farms placed under quarantine and export bans implemented No mortalities, ostriches not susceptible to virus

7 Timeline of events 1 August Western Cape state veterinarians call a meeting to discuss how to handle a potential outbreak, inviting commercial poultry farmers, veterinarians and two composters. Department of environmental affairs is also at the meeting and states that no landfilling, burial or composting of infected birds will be allowed without permits (2 year process) but concedes that may be allowed under emergency conditions. 23 August first positive test result and mortalities in commercial layer chickens in Western Cape announced and meeting arranged by state veterinarians Evening of 23 August verbal permission for emergency composting given by Director of Waste: Environmental Affairs Western Cape 24 August 2017 first layer house of chicken carcasses placed in windrows

8 Farm 1 Caged layer farm creating base layer Had to rapidly identify sources of carbon to compost chickens Choose a location for the heaps as could not compost indoors ie. Down wind from any houses, at least 60 m from water sources or boreholes, access for vehicles. Method that chickens would be placed in heaps eg. trucks, tractors etc.

Chickens placed one bale width from edge of base to ensure correct

9 Placing chickens onto heaps Chicken carcasses brought to composting area in tipper trucks, too heavy to tip so had to be done by hand. Chickens placed one bale width from edge of base to ensure correct coverage due to concern over scavenging from other birds which could spread the virus.

10 Changed to side tipper truck as volumes of carcasses were too large

11 Layering the heaps Three layers of chickens placed in each heap Ensure that no carcasses were left exposed and each layer was made of a single chicken carcass. Not always possible.

Capped with compost and agricultural plastic to

12 Completing the heaps Each layer of carcasses covered with partially composted garden waste. Capped with compost and agricultural plastic to prevent scavenging and excess leachate production in case of rain.

the heap by Department of Agriculture technicians.

13 Monitoring Once completed each heap numbered. Temperatures taken daily from three locations in the heap by Department of Agriculture technicians. Target of >55 degrees C for 3 days for virus inactivation.

14 Department of Agriculture Heap Monitoring

15 28 September 2017 opening heaps

16 Partial decomposition no flesh, but feathers and bones still very visible Heaps then turned and piled onto one another

17 17 October 2017 Material removed from poultry farm for further composting at commercial composting facility where temperatures were continued to be monitored Poultry farmers wanted the composting material removed as soon as possible as they wanted to have the quarantine lifted as soon as possible so they could operate their feed businesses and restock the farm Actually took months to achieve negative viral environment tests taken from inside poultry houses

18 Challenges Straw not biologically active and only small amount of partially composted garden waste was available. Cost was a factor. Moisture content were too low, no water available for watering heaps Only one turning was done and heaps became too small to maintain sterilisation temperatures 55 degrees Celsius for 3 days No chicken manure was added to heaps due to the fact that farm was a caged layer farm and manure was too wet to add to heaps so farmer decided to rather trench it could have been valuable in activating compost heaps Expectations of farmers that composting would happen swiftly and all material would magically disappear without any active management

19 Positive outcomes No visible leachate produced No scavenging by wild birds crows, sacred ibis, seagulls. No odour, no complaints from neighbour Virus inactivation temperatures reached after turning Large reduction in volume Commercial composter close by to complete composting process

20 Guidelines used First phase of composting given as 14 days not always possible under variable conditions Strict monitoring of temperatures 55 degrees C for 3 days for virus inactivation In-house or outside composting Composting advisor required to supervise process

21 Legislation Requirements Department of Environmental Affairs and Development Planning gave permission for emergency composting. Farms using composting need to submit request forms with details of how and where composting would take place. Department of Agriculture was responsible to temperature the compost heaps and sign off that sterilisation temperatures had been reached prior to material being removed from farms for further composting at commercial composting facilities

25 Farm 2 caged layer farm Trench being dug Finished compost heaps

26 Compost heaps between chicken houses prevailing wind not taken into account when choosing location neighbour complaints

27 Farm 3 Caged layer farm

29 Farm 4 Duck farm - composting in houses Deep litter system with concrete floors and water system in houses

manure and not in carcass layer Poor compliance from owner with respect to turning and watering

30 Very thick layers of ducks placed in heaps without carbon or manure in between so flesh still visible after 1 month of composting Very good temperatures reached in heaps, temperatures taken in manure and not in carcass layer Poor compliance from owner with respect to turning and watering heaps Eventually was convinced to get outside contractor to bring skid steers to turn and remove compost

31 Farm 5 High rise layer farm

immediately Farmer refused as wanted to start high pressure washing immediately so all material had to be

32 High Rise Chicken Houses No bedding (carbon) Purely chicken carcasses and chicken manure under cages, very high nitrogen Suggested to bring in carbon to create mixed heaps to reduce time and get composting started immediately Farmer refused as wanted to start high pressure washing immediately so all material had to be removed and composted outside Delay in emptying houses resulted in carcasses rotting fly and odour problems

33 Machinery used to remove carcasses and manure from houses

34 Carcass, manure and shredded garden waste heaps

35 Heaps laid between houses

36 First choice for most farmers bury it Trench already dug at first visit. Probably would not have been able to accommodate all material Leaching into ground water and no inactivation of virus

37 Chicken manure slurry in trenches lined with plastic sheeting. Guidelines given by Department of Environmental Affairs for burial.

38 Farm 6 Carcasses, manure and garden waste actively turned and watered

39 Impact of the Virus Outbreak Western Cape August May 2018 Total of 2,76 million layer chickens died or culled broiler breeder chickens (3 farms) ducks (2 farms) 17 backyard properties cape gannets, swift terns and 40 African penguins (suspected cases)

40 Achievements for Composting The Department of Environmental Affairs was prepared to consider composting as an effective process to handle infected animal carcasses in preference to landfilling and burial. The Department of Agriculture accepted thermophilic composting as a sterilisation technique for Highly Pathogenic Avian Influenza and took responsibility to monitor and manage farms composting their mortalities. Farmers bought into the fact that through composting it was possible, at very short notice, to handle large numbers of poultry carcasses on their farms while protecting the environment and reducing the viral load. Over 2 million birds, tons of manure and thousands of eggs were turned into compost and didn t end up in a landfill, polluting the ground water and producing methane.

41 Conclusion Never waste a crisis to be able to promote composting as the solution to a serious problem Thank you, any questions?

Avian Influenza 2003 A six months experience 21 October Ben Dellaert

Avian Influenza 2003 A six months experience 21 October 2008 Ben Dellaert Avian Influenza Virus Subtypes H1 t/m H15 N 1 t/m N9 poultry susceptible to all subtypes Low pathogenic / high pathogenic Clinical