Growth and survival of reared Cambodian field crickets (Teleogryllus testaceus) fed weeds, agricultural and food industry by-products

This study evaluated survival and growth of Cambodian field crickets (Teleogryllus testaceus) during captivity when fed a set of local weed species, agricultural and food industry by-products. Wild individuals were caught at two locations in Cambodia, kept in pens and fed commercial chicken feed until the second generation off-spring hatched. First larval stage nymphs from this generation were collected and used in a 70-day feeding trial with one control treatment (chicken feed) and 12 experimental treatments (rice bran, cassava plant tops, water spinach, spent grain, residue from mungbean sprout production, and Alternanthera sessilis, Amaranthus spinosus, Commelina benghalensis, Cleome rutidosperma, Cleome viscosa, Boerhavia diffusa and Synedrela nodiflora). The crickets were kept in plastic cages and feed intake, weight and survival of crickets were recorded weekly. Overall survival did not differ between chicken feed and the experimental treatments with the exception of crickets fed B. diffusa, which had lower survival. From day 35 to day 49, survival on A. sessilis was also lower (P<0.05) than on chicken feed. There was no difference in weight between crickets fed chicken feed, cassava tops and C. rutidosperma. However, crickets fed A. sessilis, A. spinosus and B. diffusa weighed less than those fed chicken feed already at day 21. The feed conversion rate ranged from 1.6 to 3.9 and was ≤1.9 in crickets fed chicken feed, cassava plant tops and C. rutidosperma. Thus this study shows that it is possible, using simple means, to rear Cambodian field crickets. Cassava plant tops and C. rutidosperma both have great potential as cricket feed and the other weeds, with the exception of A. sessilis, A. spinosus and B. diffusa, agricultural and food industry by-products tested, also showed potential

Growth and survival of reared Cambodian field crickets (Teleogryllus testaceus) fed weeds, agricultural and food industry by-products

This study evaluated survival and growth of Cambodian field crickets (Teleogryllus testaceus) during captivity when fed a set of local weed species, agricultural and food industry by-products. Wild individuals were caught at two locations in Cambodia, kept in pens and fed commercial chicken feed until the second generation off-spring hatched. First larval stage nymphs from this generation were collected and used in a 70-day feeding trial with one control treatment (chicken feed) and 12 experimental treatments (rice bran, cassava plant tops, water spinach, spent grain, residue from mungbean sprout production, and Alternanthera sessilis, Amaranthus spinosus, Commelina benghalensis, Cleome rutidosperma, Cleome viscosa, Boerhavia diffusa and Synedrela nodiflora). The crickets were kept in plastic cages and feed intake, weight and survival of crickets were recorded weekly. Overall survival did not differ between chicken feed and the experimental treatments with the exception of crickets fed B. diffusa, which had lower survival. From day 35 to day 49, survival on A. sessilis was also lower (P<0.05) than on chicken feed. There was no difference in weight between crickets fed chicken feed, cassava tops and C. rutidosperma. However, crickets fed A. sessilis, A. spinosus and B. diffusa weighed less than those fed chicken feed already at day 21. The feed conversion rate ranged from 1.6 to 3.9 and was ≤1.9 in crickets fed chicken feed, cassava plant tops and C. rutidosperma. Thus this study shows that it is possible, using simple means, to rear Cambodian field crickets. Cassava plant tops and C. rutidosperma both have great potential as cricket feed and the other weeds, with the exception of A. sessilis, A. spinosus and B. diffusa, agricultural and food industry by-products tested, also showed potential

Effectiveness and implementation challenges of a livestock asset transfer intervention for smallholders in community-protected areas in Cambodia

BACKGROUND: Limited opportunities to generate income in community-protected areas (CPAs) often lead to the illegal harvesting of wildlife and natural resources, undermining the aim of protected areas. Sustained livestock production can be an alternative income source. OBJECTIVES: To understand the effectiveness and feasibility of livestock production in CPAs. METHODS: We conducted a livestock asset transfer intervention in 25 CPAs across three agroecological zones in Cambodia. We monitored livestock mortality, consumption and sales of livestock over 2 years. Participant observations and structured questionnaires were conducted to elicit information about constraints for livestock production perceived by the participants. A total of 756 households were recruited and 320, 184 and 252 households received chicken, pigs and cattle, respectively. All participants received technical training in livestock production and biosecurity management practices. RESULTS: After the intervention, the number of chickens, pigs and cattle increased on average by 5.9 (range: 0.3-26.3), 0.5 (-1 to 2.7) and 0.12 (0-0.35) per 1 input animal, respectively. The extent of increase was significantly different between zones only for chickens (Kruskal-Wallis test p = 0.004). The number of chickens and pigs sold per household was significantly different among zones. We observed that training was ineffective to alter livestock management practices in some CPAs, which partially explains their suboptimal performance of livestock production. CONCLUSIONS: Understanding contextual factors required for successful livestock production in CPAs is crucial for improving livelihoods and preventing biodiversity loss in Cambodia

Quantitative risk assessment of salmonellosis in Cambodian consumers through chicken and pork salad consumption

Salmonella is a globally important foodborne bacterial pathogen that poses a high risk to human health. This study aimed to estimate the risk to Cambodian consumers from acquiring salmonellosis after consuming chicken and pork salad, using a quantitative microbial risk assessment (QMRA). Chicken and pork salads are typical Cambodian dishes containing raw vegetables and boiled chicken meat or pork. As previously described, chicken meat and pork samples (n = 204 of each) were collected from traditional markets in 25 Cambodian provinces to generate data on Salmonella contamination. Salad preparation and consumption practices were surveyed in 93 Cambodian households and this information was used to design an experiment to assess Salmonella cross-contamination from raw meat to ready-to-eat salad. In the part of the study reported here, data on consumption, Salmonella in salad, dose-response, and predicted salmonellosis were modeled using Monte Carlo simulations at 10,000 iterations. The prevalence of Salmonella in chicken meat and pork were set to 42.6 and 45.1%, respectively, with average most probable number (MPN) per gram of Salmonella in chicken meat was 10.6 and in pork 11.1 MPN/g, based on an earlier study. Half of the interviewed households cooked meat for the salad directly after purchase. The QMRA model showed that the modeled annual risk of salmonellosis from consuming chicken salad, pork salad and both chicken and pork salad were 11.1% probability of illness per person per year (90% CI 0.0–35.1), 4.0% (90% CI 0.0–21.3), and 14.5% (90% CI 0.0–33.5), respectively. The factors most influencing the estimate were cross-contamination while preparing the salad, followed by the prevalence of Salmonella in chicken meat and pork at the market. The wide confidence interval for the incidence was mainly due to the variability in reducing bacteria concentration by cooking and salad consumption. The predicted risk of salmonellosis due to chicken and pork salad consumption is high, and the study provides evidence supporting control measures of improving the safety of retailed chicken and pork obtained from markets to households and improving food preparation methods in the household

Experimental cross-contamination of chicken salad with Salmonella enterica serovars Typhimurium and London during food preparation in Cambodian households

Non-typhoidal Salmonellae are common foodborne pathogens that can cause gastroenteritis and other illnesses in people. This is the first study to assess the transfer of Salmonella enterica from raw chicken carcasses to ready-to-eat chicken salad in Cambodia. Twelve focus group discussions in four Cambodian provinces collected information on typical household ways of preparing salad. The results informed four laboratory experiments that mimicked household practices, using chicken carcasses inoculated with Salmonella. We developed four scenarios encompassing the range of practices, varying by order of washing (chicken or vegetables first) and change of chopping utensils (same utensils or different). Even though raw carcasses were washed twice, Salmonella was isolated from 32 out of 36 chicken samples (88.9%, 95% CI: 73.0–96.4) and two out of 18 vegetable samples (11.1%, 95% CI: 1.9–36.1). Salmonella was detected on cutting boards (66.7%), knives (50.0%) and hands (22.2%) after one wash; cross-contamination was significantly higher on cutting boards than on knives or hands (p-valu

Diarrhea illness in livestock keeping households in Cambodia: An analysis using a One Health framework

Background: Most of human diarrheal pathogens are zoonotic, and transmission of the pathogens can occur by contaminated food, water, environment and direct contact with animals especially for livestock keepers. Yet little is known of the relative importance of different risk factors especially in under-studied countries. The objectives of this study were to identify risk factors for diarrhea in livestock keepers in Cambodia and detect diarrhea-causing pathogenic bacteria in both humans and livestock within a One Health approach. Of special interest were the links between diarrhea and food consumption and livestock-keeping. Materials and methods: We used an existing dataset from a questionnaire survey conducted in 400 livestock farms in Prey Veng and Kampot Prefectures between February and March 2013 as well as laboratory results on bacterial isolation from fecal and swab samples from livestock and poultry, and human stool samples. Laboratory results were available for up to three animals of each species kept by a household, and for up to three human samples from households reporting at least one case of human diarrhea in the previous 2 weeks. Presence of Escherichia coli, Shigella spp. and Salmonella spp. was investigated in both animal and human samples, in addition to Aeromonas spp., Vibrio spp. and Plesiomonas spp. in animal samples and Campylobacter spp. in human samples. Univariable and multivariable risk factor analyses were performed by generalized linear mixed model. Results: Household-level diarrhea incidence rate was 9.0% (36/400). The most statistically significant factor associated with diarrhea in multivariable analysis was water treatment for drinking and cooking (OR = 0.33, 95%CI: 0.16–0.69, p = 0.003), followed by number of days consuming egg within 2 weeks (OR = 1.16, 95%CI: 1.04–1.29, p = 0.008), number of children under 5 years old (OR = 1.99, 95%CI: 1.14–3.49, p = 0.016) and keeping poultry (OR = 0.36, 95%CI: 0.14–0.92, p = 0.033). Animal samples for bacterial culture test were collected at 279 cattle, 165 pig and 327 poultry farms, and bacteria were detected from 6 farms with the isolation of Escherichia coli O157 (non H7) from 1 cattle and 1 pig sample, Aeromonas caviae from 1 pig sample and Salmonella spp. from 3 chicken samples. In human samples, 17 out of 67 individual samples were positive for the culture test, detecting Escherichia coli O157 (non H7) from 7 samples and Shigella spp. from 10 samples. None of the households where target bacteria were detected from animal samples had human samples collected due to lack of diarrhea episodes in the household. Conclusions: It has often been hypothesized that keeping livestock may increase the incidence of diarrhea through multiple pathways. Contrary to this, we found livestock-keeping was not associated with increased risk, but food-related behavior and children under 5 years of age were strongly associated with increased risk. We discuss mediating and confounding factors and make recommendations for reducing the burden of diarrheal disease in Cambodia and more widely in low- and middle-income countries