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Characterization of Small-Scale Antibiotic-Free Broiler Production in Minnesota

J. P. Jacob^*,1, J. P. Griggs^* and J. B. Bender

^* Department of Animal Science, and Veterinary Population Medicine, University of Minnesota, 1354 Eckles Ave., St. Paul 55108

¹ Corresponding author: jacquie.jacob{at}uky.edu

	SUMMARY

TOP SUMMARY DESCRIPTION OF PROBLEM MATERIALS AND METHODS RESULTS AND DISCUSSION CONCLUSIONS AND APPLICATIONS REFERENCES AND NOTES

 
The purpose of this study was to characterize the production practices of small antibiotic-free flock producers and identify the possible points for introduction of food-borne pathogenic bacteria. These data will be used to develop appropriate extension programs to improve the level of biosecurity on such farms. Minnesota poultry producers who raised flocks of meat-type chickens without antibiotics were interviewed either on their farms or via the telephone. A wide diversity of housing and management styles were disclosed. Key areas identified for extension programs include feed and pasture choice, waste disposal, feed withdrawal before slaughter, and marketing.

Key Words: broiler • small flock • Minnesota

	DESCRIPTION OF PROBLEM

TOP SUMMARY DESCRIPTION OF PROBLEM MATERIALS AND METHODS RESULTS AND DISCUSSION CONCLUSIONS AND APPLICATIONS REFERENCES AND NOTES

 
The US poultry industry has grown significantly over the last 2 decades because of increased per capita consumption and a move toward industrialization and vertical integration. Broiler production in the United States is one of the most vertically integrated industries in the food production sector. This integration keeps the price of poultry products low but has forced small producers to consider alternative production systems, whether it be a change in the species reared or management practices used.

While scientists, industry personnel, politicians, and concerned citizens continue to debate the issue of antibiotic use in animal production, a growing number of independent farmers are marketing poultry raised without the use of antibiotics. The production systems used by these producers differ considerably from those of the larger, conventional producers. In most cases, the chickens are kept outdoors for at least part of the growing period. This change in flock management creates opportunities to introduce diseases formerly controlled in poultry production. This includes opportunities for product contamination with food safety pathogens such as Salmonella and Campylobacter, which can be carried by a variety of other animals, including pigs, turkeys, cattle, dogs, and cats.

Many small flock producers believe that chickens raised without antibiotics will have less bacterial contamination than conventionally grown birds [1]. In reality, however, these antibiotic-free chickens may actually be at greater risk of being infected with food-borne illness-causing bacteria, including antibiotic-resistant bacteria [2].

Currently, there is limited published information regarding the management, feeding, and rearing of small chicken flocks in the United States. The purpose of this study was to characterize the production practices of small antibiotic-free flock producers in Minnesota and identify the critical points for the introduction of food-borne pathogenic bacteria into the flock. These data will be used to develop appropriate extension programs to improve the level of bio-security on such farms.

	MATERIALS AND METHODS

TOP SUMMARY DESCRIPTION OF PROBLEM MATERIALS AND METHODS RESULTS AND DISCUSSION CONCLUSIONS AND APPLICATIONS REFERENCES AND NOTES

 
Producers who grow broiler chickens for a niche market (antibiotic-free) were identified from local custom processing plants as part of a previous study [3]. These producers were contacted by phone to schedule an on-farm interview. Twelve of the original 20 producers agreed to participate. A standardized survey instrument was used. The survey questions covered various topics related to producer experience, source of chickens, size of the flock, housing, feed, mortality, biosecurity practices, and marketing.

An additional 44 broiler producers were identified from a list of local producers of agriculture products published by the Minnesota Department of Agriculture [4]. Producers were contacted by phone. Thirty-two (73%) of the 44 broiler producers willingly participated in a shortened standardized survey. The standardized survey was conducted over the phone with a subset of the questions used from the on-farm survey.

The number of broilers sold each year was similar between the groups represented in the on-farm interview data set and the phone interview data set. As a result, the data sets for the common survey questions for both the on-farm and phone surveys were combined and summarized.

The survey was approved by the Institutional Review Board of the University of Minnesota. The Institutional Review Board reviews research projects with human subjects and works with investigators to ensure adequate protection and informed, uncoerced consent.

	RESULTS AND DISCUSSION

TOP SUMMARY DESCRIPTION OF PROBLEM MATERIALS AND METHODS RESULTS AND DISCUSSION CONCLUSIONS AND APPLICATIONS REFERENCES AND NOTES

 
Overall, producers from 29 Minnesota counties were represented. Eleven counties were represented in the on-farm interviews, and 24 were represented in the phone interviews. Six counties had producers who participated in either the on-farm or the phone survey.

Flock Size
The average number of chickens a producer marketed annually ranged from 50 to 20,000. The average was 2,048 and the median 830 (Figure 1). For the 12 contacts participating in the on-farm interviews, individual flock size varied from 100 to 350 chickens, with an average of 189 and a median of 200.

View larger version (16K): [in this window] [in a new window]   Figure 1. Overview of size of farms interviewed, based on the responses of the 41 producers interviewed who responded to the question related to the number of meat-type chickens per farm marketed annually.

Poultry Production Experience
Table 1 is a summary of the poultry production experience that producers had in chicken meat production, antibiotic-free production, or both. All the producers had some previous experience raising poultry, but the level of experience varied considerably, from 1 to 65 yr (Figure 2). The producer who had been raising poultry for 65 yr had been raising meat chickens for 33 yr, and at the time of the interview was in his first year of raising antibiotic-free broilers.

View larger version (11K): [in this window] [in a new window]   Figure 2. Distribution of the total number of years of poultry-related experience of the producers interviewed (n = 44).

Source and Type of Chicks
In a single production season, each of the producers received the chicks from a single hatchery source. A total of 13 different hatcheries were used by the 42 producers responding to this question. Thirty (71.4%) of the 42 producers indicated that they purchased their chicks from 1 of 4 hatcheries in Iowa. Three (7.1%) producers purchased their chicks from a Minnesota hatchery. All of these hatcheries are National Poultry Improvement Plan (NPIP) certified [6].

Forty (90.9%) of the 44 producers raised a Cornish Cross as their breed of choice, whereas the remaining 4 producers raised Black Australorps (n = 2), White Rocks (n = 1), or Red Broilers (n = 1). The Australorp was developed in Australia as an egg layer. In the United States, it is the meat bird preferred by some of the ethnic populations in the Midwest because of its black feathers and dark shanks. The Red Broiler is a meat-type chicken also favored for its darker skin. It typically reaches 3 to 4 lb (1.4 to 1.8 kg) in 8 wk and is slightly smaller than the Cornish Cross. The White Rock is a dual-purpose chicken and is typically raised to 5.5 to 6 lb (2.5 to 2.7 kg) in 12 to 14 wk.

Chicks were obtained by 3 methods, with some producers using more than 1 method throughout the growing season. Twenty-three (52.3%) of the 44 producers had their chickens delivered via the US Postal Service. Half of the producers picked up their chickens directly from the hatchery. Fourteen (32%) producers had the chicks delivered directly to the farm. Some producers used a combination of methods, including having chicks sent to the local cooperative and then being picked up by the producer.

Housing and Pasture
Forty-three (97.7%) of the 44 producers started their broilers in a barn or another type of enclosed building. One producer grew certified organic broilers and started chicks on pasture from 5 d. It was assumed that supplemental heat was provided for the first few weeks, but this question was not asked in the survey.

Thirty-four (77.3%) of the 44 producers used pine shavings as the litter material in their barns. Two of these producers also used aspen shavings. Other litter materials used included straw (n = 14), paper (n = 7), wood chips (n = 1), and oat hulls (n = 1). Sixteen producers (36.4%) used more than 1 type of material as litter. One producer used corncobs with the pine shavings and another combined pine shavings with cardboard.

All but 4 of the producers in this study gave their chicks access to the outdoors when they reached a certain age. The age at which the birds had access to pasture, and the amount of access, varied from farm to farm. The average age at which broilers had access to pasture was 24 d (range: 5 to 42 d; median: 21 d). Chicks are typically able to regulate their own body temperature at 3 wk of age. The environmental temperature will have an effect on the age at which the chicks should be placed on pasture. Most producers raising small backyard flocks in the Midwest (91%) provide outdoor access for their chickens [7].

Four different types of outdoor access were identified: no access (did not allow the broilers outside); day-range (chickens were allowed out of their house during daylight hours only); free-range (chickens had access to the outside day and night); or movable pasture pens (chickens were housed on pasture in covered, bottomless pens that were moved to fresh pasture on a regular basis). The number of producers using each system, and the average number of chickens marketed annually for producers using each system, is shown in Table 2. The moveable pen system, which can be very labor intensive, was used primarily by the producers marketing fewer than 500 chickens per year. Access was not provided by 4 of the larger producers, which reduced their labor load. Larger flocks on pasture typically have more visible feeding areas, which could attract passing wild birds, increasing the likelihood of bacterial contamination.

Many of the producers used the pasture for multiple purposes. On 19 farms, the chicken pasture was used by another species at some point during the year. Two farms had additional animals using the same pasture at the same time as the broilers; the additional animals included llamas and laying hens. Animals using the pasture before the chickens included cattle (dairy or beef), sheep, horses, goats, llamas, and donkeys. Other poultry species using the pasture included laying hens and geese. For most of the farms, the chickens were placed on the same pasture within 2 wk of being used by other animals.

Having multiple species using a pasture allows for maximum use of the pasture, but the raising of other livestock on the farm has been reported to contribute to the presence to Campylobacter in a chicken flock [12]. In addition, it has been reported that Campylobacter bacteria can be spread from a herd of cattle to a chicken flock on the boots of farm workers [13].

Biosecurity Practices
None of the producers visited had identifiable biosecurity measures, such as footbaths or screens over the windows to prevent rodent or other wild animal access to the chicken flock. Twenty-eight (63.6%) of the 44 producers raised other types of poultry. It was unclear whether these other types of poultry received antibiotics.

Two (16.7%) of the 12 producers who participated in on-farm interviews had house cats and 1 had a hamster and finches. Although these animals do not interact with the farm animals, they do interact with the people that care for both. Eight (66.7%) of the 12 producers indicated that they had used an antibiotic to treat other animals on the farm. The antibiotics used included penicillin, oxytetracycline, chlortetracycline, ciprofloxacin, tylosin, enrofloxacin, microtil, and gentamycin. Information on the use of antibiotics in livestock production is available on the USDA-Animal and Plant Health Inspection Service Web site [14].

Ten of the 12 producers indicated that a variety of animals, both domestic and wild, are known to interact with the meat chickens. The species included cats, dogs, opossums, rodents, raccoons, badgers, chipmunks, skunks, wild birds, guinea fowl, and turkeys. Wild birds shed Campylobacter and Salmonella in their droppings [15]. Mice are an important ongoing source of Salmonella, especially Salmonella Enteritidis [16].

Nine (24.3%) of the 37 producers who responded to this question on the survey indicated that their chicks were vaccinated at the hatchery, mainly for Marek’s disease. Marek’s disease virus is universally found in the environment. As a result, nearly all chicks are exposed to Marek’s disease virus within days of hatching. Vaccination is recommended only in areas where the disease is a known problem. One producer had chicks vaccinated for Newcastle disease, infectious bronchitis, and coccidiosis.

Producers who participated in on-farm surveys were asked specific biosecurity questions related to barn cleaning and disinfection. Four (25%) of these 12 producers reported using a disinfectant. Three used bleach and 1 reported using chlorine as a disinfectant in the barn. Salmonella bacteria can survive in a broiler house for prolonged periods of time (up to 12 mo) even after the flock is removed [17]. Time between flocks in the same barn for producers raising more than 1 flock per year varied between one-half day (12 h) and 2 mo. The average time between flocks was 21 d, with a median time of 12 d. Seven producers allowed only 1 d or less between flocks placed in the same barn.

Three producers shared equipment with other poultry farms. One producer lent his transportation crates to other farms, and another producer borrowed cages and transportation crates.

Morbidity and Mortality
Predators accounted for some losses in the broiler flocks, although the occurrence was low. Thirty-six (82%) of the 44 producers reported losing 5% or less of their flock to predators. For those losing more than 5% to predators, 1 producer reported losing 10%, 2 estimated 15%, 2 lost 20%, and 1 lost 30%. Predator losses have been one factor limiting the use of day- and free-range housing systems.

Thirty-two (73%) of the 44 producers reported that in the past 3 yr, they had not lost many chickens (<5%) to disease or other health-related problems. Of the 11 producers (25%) that reported having a disease outbreak in their flocks within the past 3 yr, 4 producers (9.1%) reported having problems with coccidiosis, 2 of which were confirmed by a diagnostic laboratory. Two producers (4.5%) reported problems with Salmonella spp., and both cases were confirmed by a diagnostic laboratory. One of these producers treated the flock with antibiotics. One producer (2.3%) reported a laboratory-confirmed case of Marek’s disease. Our results are similar to a survey conducted in California that reported that 89% of backyard flock producers did not observe any significant health problems in their flocks [18].

When asked if they would use antibiotics if they had a disease outbreak, 24 producers (55%) said that they would use antibiotics to treat their flocks. Thirteen producers (30%) would not use antibiotics even if the disease outbreak could be managed with antibiotics. Seven producers (16%) did not know whether they would use antibiotics in that situation. One of these producers was raising certified organic broilers, and the use of antibiotics would mean they could not sell their products as organic. The organic regulations do specify that if a disease outbreak cannot be treated with alternative methods, the flock must be treated with antibiotics, separated from the organic flock, and sold as nonorganic. Probiotics were used by 11 (25%) producers.

Waste Disposal
Producers used different methods to dispose of litter. Twenty-six (60%) of the 43 producers who responded to this question on the survey composted the litter on their farm. One producer reused the litter as calf bedding. Sixteen producers (37%) spread the litter somewhere on their farms without composting. One producer reported putting the litter in a pile on the farm. None of the producers disposed of the litter off their farms. Five (42%) of 12 producers with whom on-farm surveys were conducted reported that they composted dead broilers. Three (25%) incinerated dead broilers. No producers reported burying dead broilers, which is illegal in many states. Other methods used to dispose of dead broilers included feeding them to the cat or spreading them on a field without composting (n = 1), placing them in a dumpster near the broiler barn (n = 1), lacing them with poisons for predators to find (n = 2), and using them to culture fly maggots to feed to the other chickens (n = 1). Dead chickens disposed of by these latter methods could contribute to disease outbreaks on the farm. Composting is helpful to reduce pathogen concentration and prevention of disease transmission [19].

With the producers interviewed, the choice to compost or not appears to be related to the number of chickens marketed each year. Although composting was used by farmers marketing 50 to 10,000 chickens annually, overall these farms were larger than those that did not compost.

Feed
Commercial broilers are commonly fed different rations throughout their lives. Such rations are formulated to meet the chicken’s different nutritional requirements as they grow. The type, form, and frequency of feeds used by the producers surveyed are listed in Table 3.

Poultry feeds can be purchased in several forms, with the most common being mash, crumbles, and pellets. No producers fed pellets at any time during the rearing of their broilers. Pellets can be produced only in feed mills with a pellet mill, and most small feed mills do not possess one. Although no producers indicated that they fed pellets, 15 producers fed crumbles at least once during the rearing period. The lack of a pellet mill therefore does not explain why no producers fed pellets. Seven of the producers interviewed (16%) started their broilers on a diet made of whole grains.

One producer indicated that animal by-products were included in his rations. Nine producers said they did not know if animal by-products were included in their feed. Four producers (17%) reported that fishmeal was present in their first ration.

Processing
To reduce fecal contamination of carcasses, feed is typically removed from the flock before slaughter. The optimum withdrawal time for conventionally raised chickens is 8 to 10 h. The 12 producers who participated in the on-farm interviews were asked about their feed withdrawal program. Nine producers (75%) reported that they withdrew feed from the chickens before slaughter. The average and median amount of time that feed was withdrawn before slaughter was 12 h, ranging from 10 to 16 h. The optimum feed withdrawal time for chickens raised on pasture has not been determined. In pasture systems, when feed is removed the chickens will consume forage and can arrive at the processing plant with full crops.

Four of the 12 producers reported taking their broilers off water before slaughter. Among those 4, the average amount of time the broilers were without water before slaughter was 11 h, with a range from 8 to 12 h.

These 12 producers were also asked how they transported their broilers to the processing facility. Eight (67%) reported using their own vehicle and 4 (33%) said they used a borrowed vehicle or paid someone else to transport their flock to the processing facility. The average distance that a flock was transported was 43 miles (69.2 km), ranging from 9 to 80 miles (14.5 to 128.7 km). The average time to get from their farm to the processing facility was 56 min (median of 60 min). The maximum transportation time was 90 min and the minimum was 20 min. One producer processed his chickens on farm.

Sales and Marketing
Poultry processing plants where small flock owners can get their poultry processed are classified as 1 of 3 types of plants: custom slaughter only, state inspected or equal to (E2), or federally inspected. Plants with "custom processing" or "custom exempt" status do not have on-site inspection of the birds as they are processed, although the facility is inspected periodically. The processed birds can only go back to the owner for home consumption. It is not possible to sell the custom-processed birds at farmers’ markets, restaurants, or groceries. Plants with E2 status do have on-site state inspection of the birds. They are labeled with the "Minnesota Inspected and Passed" state seal of inspection. The processed birds can be sold within the state of Minnesota at farmers’ markets (if you have a food handler’s license), restaurants, or grocery stores. In addition, processors can help with the marketing of processed birds. Minnesota State-inspected birds cannot be transported for sale across the state line. Plants with federal status have on-site USDA inspection of the birds. They are labeled with the USDA seal of inspection and can be sold anywhere in the United States.

Thirty-two (73%) surveyed producers reported that they usually have their chickens processed at an E2 facility. Only 6 producers (16%) had their chickens processed at facilities with USDA inspection. The remaining 6 producers had no inspection performed on their flock during processing.

A variety of marketing methods were used by the 44 producers interviewed, with many producers using more than 1 method. Fourteen producers (32%) indicated that they sold at least a portion of their chickens at a farmer’s market. Six producers (13.6%) sold only to neighbors and friends. Only 6 (13.6%) of the 44 producers sold chickens to restaurants, groceries, or other retail stores. Two producers (4.5%) raised their chickens specifically for the Asian community. Although it was common for producers to report relying on word of mouth to attract new customers, 13 (30%) reported they did some kind of advertising, including using the Internet.

One frequently asked question for extension services relates to how producers can market their product. Many farmers are good at producing poultry products but lack the skills necessary to sell their products in sufficient quantity and at a price that will allow them to make a profit.

	CONCLUSIONS AND APPLICATIONS

TOP SUMMARY DESCRIPTION OF PROBLEM MATERIALS AND METHODS RESULTS AND DISCUSSION CONCLUSIONS AND APPLICATIONS REFERENCES AND NOTES

 

1. There was a wide diversity of management styles for producers of small chicken flocks.
   
2. Most producers of small chicken flocks provided outdoor access for their birds.
   
3. Diseases were not identified as a significant problem in small chicken flocks.
   
4. Most producers sold processed chicken through niche markets such as farmers’ markets, direct marketing, Community Support Agriculture, health stores, or ethnic communities.
   
5. An understanding of management practices of small-scale producers is necessary to provide appropriate management, biosecurity training, and education.
   

	ACKNOWLEDGMENTS

 
This research was funded by a grant from the Rapid Agricultural Research Fund (RARF) of the College of Food, Agriculture and Natural Resources Sciences (CFANS) at the University of Minnesota. We would like to thank the Minnesota Department of Agriculture for identifying the original 12 producers we interviewed for this study, as well as publishing the Minnesota Grown directory of local producers through which we found the other 32 participants. We would also like to thank the 44 producers who participated in the survey for their time and patience.

	REFERENCES AND NOTES

TOP SUMMARY DESCRIPTION OF PROBLEM MATERIALS AND METHODS RESULTS AND DISCUSSION CONCLUSIONS AND APPLICATIONS REFERENCES AND NOTES

 

1. Bailey, J. S., and D. E. Cosby. 2005. Salmonella prevalence in free-range and certified organic chickens. J. Food Prot. 68:2451–2453.[Web of Science][Medline]
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3. Griggs, J. P., J. B. Bender, and J. P. Jacob. 2006. Microbial safety of chicken raised without antibiotics. J. Appl. Poult. Res. 15:475–482.[Abstract/Free Full Text]
4. Minnesota Department of Agriculture. Minnesota Grown. http://www.mda.state.mn.us/food/minnesotagrown/ Accessed Jan. 2008.
5. Berndtson, E., U. Emanuelson, A. Engvall, and M.-L. Danielsson-Tham. 1996. A 1-year epidemiological study of Campylobacter in 18 Swedish chicken farms. Prev. Vet. Med. 26:167–185.[CrossRef][Web of Science]
6. National Poultry Improvement Plan (NPIP), Conyers, GA. http://www.aphis.usda.gov/animal_health/animal_dis_spec/poultry Accessed Jan. 2008.
7. USDA. 2005. Part I: Reference of Health and Management of Backyard/Small Production Flocks in the United States, 2004. No. N432.0805. USDA, Animal and Plant Health Inspection Service (APHIS), National Animal Health Monitoring System (NAHMS), Fort Collins, CO.
8. Kennard, D. C. 1951. Forages for poultry. Chap. 60. Ohio Agric. Exp. Stn., Columbus.
9. Morrison, F. B. 1954. Feeds and Feeding. Abridged ed. The Morrison Publishing Company, Ithaca, NY.
10. Sustainable Agriculture Network (SAN). 2002. Profitable Poultry: Raising Birds on Pasture. USDA, Sustainable Agriculture Research and Education, Washington, DC.
11. Sheaffer, C. C. 2005. Pastures for chickens. Presented at the 2005 Midwest Poultry Federation Convention, Minneapolis, MN, March 15–17, 2005.
12. Hald, B., A. Wedderkopp, and M. Madsen. 2000. Thermophilic Campylobacter spp. in Danish broiler production: A cross-sectional survey and a retrospective analysis of risk factors for occurrence in broiler flocks. Avian Pathol. 29:123–131.[CrossRef][Web of Science][Medline]
13. Van De Giessen, A. W., J. J. H. C. Tilburg, W. S. Ritmeester, and J. Van Der Plas. 1998. Reduction of Campylobacter infections in broiler flocks by application of hygiene measures. Epidemiol. Infect. 121:57–66.[CrossRef][Medline]
14. USDA, Animal and Plant Health Inspection Service. 2006. Antibiotic Use in U.S. Livestock Production. http://www.aphis.usda.gov/vs/ceah/cei/taf/emerginganimalhealthissues_files/antiresist.antibiouse.pdf Accessed May 2008.
15. Craven, S. E., N. J. Stern, E. Line, J. S. Bailey, N. A. Cox, and P. Fedorka-Cray. 2000. Determination of the incidence of Salmonella spp., Campylobacter jejuni, and Clostridium perfringens in wild birds near broiler chicken houses by sampling intestinal droppings. Avian Dis. 44:715–720.[CrossRef][Web of Science][Medline]
16. Davies, R. H., and C. Wray. 1996. Persistence of Salmonella enteritidis in poultry units and poultry feed. Br. Poult. Sci. 37:589–596.[Web of Science][Medline]
17. Davies, R. H., and C. Wray. 1996. Studies of contamination of three broiler breeder houses with Salmonella enteritidis before and after cleansing and disinfection. Avian Dis. 40:626–633.[CrossRef][Web of Science][Medline]
18. McBride, M. D., D. W. Hird, T. E. Carpenter, K. P. Snipes, C. Danaye-Elmi, and W. W. Utterback. 1991. Health survey of backyard poultry and other avian species located within one mile of commercial California meat-turkey flocks. Avian Dis. 35:403–407.[CrossRef][Web of Science][Medline]
19. Anthony, W. B., and R. Nix. 1962. Feeding potential of reclaimed fecal residue. J. Dairy Sci. 45:1538–1539.[Abstract/Free Full Text]

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