Mammalian pest problems in organic pig farming, preventive measures and control

Organic pig farming includes having pigs in open fields with relatively close contact to the wild fauna. The risk of transmission of parasites and diseases to the pigs is therefore higher than in traditional pig farming with pigs under strict control in indoor pigsties. Newborn and sucking pigs are also exposed to predators that may cause losses to the farmers. A general trend in organic farming is to avoid the use of pesticides. There is therefore a need for effective preventive measures and control methods that are acceptable to the organic farmers. As a first step in a project for developing strategies for pest management in organic pig farming we conducted a questionnaire survey in Denmark. The farmers were asked questions about what they considered problems arising from the natural environment. They were also asked to describe how they offered fodder and water, which types of huts they used etc. The surroundings should be described regarding factors that were thought to influence the natural fauna, such as e.g. distance to quickset hedges, forests, streams and watercourses. The results of the survey showed that rats and smaller rodents (mice and voles), foxes and hares were the most frequently occurring mammals in the fields with pigs. The farmers considered rats and foxes as causing the most important (pest) problems. Occurrence of rats is reported significantly more frequently in organic pig farming than in traditional pig farming in open fields. The answers given by the farmers were analysed as to possible relationships between occurrence of / problems with rodents and the practice regarding the pig farming. There was a significant positive correlation between occurrence of rats, smaller rodents and foxes. Use of automatic feeding systems and open water trays, and having stacks of hay and straw in the fields were all factors that were significantly positively correlated with the occurrence of rats and smaller rodents. The occurrence of smaller rodents was negatively correlated with the use of huts with a bottom and huts made of hard materials. Special shelters for the pigs exclusively made of bales of straw did not give a significant positive correlation with occurrence of rodents. These results indicate factors that are practicable as preventive measures against rodents. The farmers reported traps, shooting, and cats and dogs as the most frequent non-chemical ways of controlling rodents

Non-poisonous means for reducing rodent pest problems in organic pig farming

The results indicate factors that are practicable as preventive measures against rodents. Preventive measures are to be considered when planning and laying out the fields for the pigs and when running the farm as well

Gode ideer til giftfri muse- og rottebekæmpelse

I økologisk produktion er det stadig tilladt at anvende antikoagulanter til rottebekæmpelse. Kan brug af kemiske bekæmpelsesmidler i de økologiske bedrifter helt undgås, vil det være i god overensstemmelse med det grundlæggende koncept. Ved avl af frilandsgrise er der yderligere den faktor, at man er meget tættere på den frie natur, så ved brug af kemiske bekæmpelsesmidler har man en potentiel risiko for at påvirke og forgifte ikke-måldyr, altså de dyr der forekommer og ikke optræder som uønskede skadedyr. For at undgå problemer med mus og rotter er de forebyggende foranstaltninger en vigtig forudsætning, og disse skal overvejes både ved etablering og ved den daglige drift. Derved kan den egentlige bekæmpelse begrænses væsentligt

On-farm maize storage systems and rodent postharvest losses in six maize growing agro-ecological zones of Kenya

Rodents are one of the major postharvest pests that affect food security by impacting on both food availability and safety. However, knowledge of the impact of rodents in on-farm maize storage systems in Kenya is limited. A survey was conducted in 2014 to assess magnitudes of postharvest losses in on-farm maize storage systems in Kenya, and the contribution of rodents to the losses. A total of 630 farmers spread across six maize growing agro-ecological zones (AEZs) were interviewed. Insects, rodents and moulds were the main storage problems reported by farmers. Storage losses were highest in the moist transitional and moist mid-altitude zones, and lowest in the dry-transitional zone. Overall, rodents represented the second most important cause of storage losses after insects, and were ranked as the main storage problem in the lowland tropical zone, while insects were the main storage problem in the other AEZs. Where maize was stored on cobs, total farmer perceived (farmer estimation) storage weight losses were 11.1 ± 0.7 %, with rodents causing up to 43 % of these losses. Contrastingly, where maize was stored as shelled grain, the losses were 15.5 ± 0.6 % with rodents accounting for up to 30 %. Regression analysis showed that rodents contributed significantly to total storage losses (p < 0.0001), and identified rodent trapping as the main storage practice that significantly (p = 0.001) lowered the losses. Together with insecticides, rodent traps were found to significantly decrease total losses. Improved awareness and application of these practices could mitigate losses in on farm-stored maize

Factors correlated with the presence of rodents in outdoor pig farms in Denmark and suggestions for management strategies

The correlation between farm characteristics and the occurrence and importance of rodent pests on outdoor pig farms in Denmark was explored in an extensive questionnaire survey. Mice occurred on most farms but were only rarely considered a problem, as opposed to rats, which were controlled on more than half of the farms. A series of trapping studies showed a high small-mammal diversity in and around the pigsties. The presence of rats was positively correlated with farm size, the presence of straw stacks near the pigsties and the use of automatic feeders. Rats were considered a problem more often when open drinking basins were used or when feed was stored near the pigsties. The environment of the farm did not play an important role except to some extent the proximity of hedges. Recommendations for preventative rodent management include avoiding these conditions, frequent mucking out and movement of huts, keeping feed in rodent-proof containers, avoid spillage of fodder, and general cleanliness. Direct control methods include application of rodenticides with proper consideration for the risk of unintended poisoning of production animals, the use of traps, keeping dogs or cats, and possibly shooting

Evaluation of thiram and cinnamamide for protection of maize seeds against multimammate mice, **Mastomys natalensis**, in Tanzania

Belgian Journal of Zoology 2015; 135 (supplement) : 179-181Farmers in Tanzania consider rodents to be the major vertebrate pest of maize, especially at planting and seedling stages and annual losses are high. We evaluated the potential of two seed-dressing compounds, thiram and cinnamamide, as rodent repellents to protect maize against damage by multimammate rats, Mastomys natalen- sis. In laboratory tests, the two compounds showed a strong repellent effect against M. natalensis and thus the potential to protect maize seeds. The two compounds were evaluated in maize fields using Randomized Complete Block Design (RCBD) with three replications. The results show that these repellents are effective for protecting maize seeds against multimammate rats in the field, but in locations with high population of Tatera leucogaster, seedlings are still damaged after emergence. Therefore, in such locations, other control measures, including applica- tion of rodenticides just before seedling emergence may be necessary