Antibody expressing pea seeds as fodder for prevention of gastrointestinal parasitic infections in chickens

<p>Abstract</p> <p>Background</p> <p>Coccidiosis caused by protozoans of genus <it>Eimeria </it>is a chicken parasitic disease of great economical importance. Conventional disease control strategies depend on vaccination and prophylactic use of anticoccidial drugs. Alternative solution to prevent and treat coccidiosis could be provided by passive immunization using orally delivered neutralizing antibodies. We investigated the possibility to mitigate the parasitic infection by feeding poultry with antibody expressing transgenic crop seeds.</p> <p>Results</p> <p>Using the phage display antibody library, we generated a panel of anti-<it>Eimeria </it>scFv antibody fragments with high sporozoite-neutralizing activity. These antibodies were expressed either transiently in agrobacteria-infiltrated tobacco leaves or stably in seeds of transgenic pea plants. Comparison of the scFv antibodies purified either from tobacco leaves or from the pea seeds demonstrated no difference in their antigen-binding activity and molecular form compositions. Force-feeding experiments demonstrated that oral delivery of flour prepared from the transgenic pea seeds had higher parasite neutralizing activity <it>in vivo </it>than the purified antibody fragments isolated from tobacco. The pea seed content was found to protect antibodies against degradation by gastrointestinal proteases (>100-fold gain in stability). <it>Ad libitum </it>feeding of chickens demonstrated that the transgenic seeds were well consumed and not shunned. Furthermore, feeding poultry with shred prepared from the antibody expressing pea seeds led to significant mitigation of infection caused both by high and low challenge doses of <it>Eimeria </it>oocysts.</p> <p>Conclusion</p> <p>The results suggest that our strategy offers a general approach to control parasitic infections in production animals using cost-effective antibody expression in crop seeds affordable for the animal health market.</p

Provision of perches and their use by broiler breeders on the basis of a case study

All individuals of the species Gallus gallus, also broiler breeders, have a preference of resting on elevated areas but only few studies have focused on the resting behaviour of broiler breeders. The aim of the present study was to determine the status quo of perch use on conventional broiler breeder farms. Therefore, nine commercial broiler breeder flocks with the fast growing genetics Ross 308 and Ross 708 and the slow growing genetics Ross Ranger in Lower Saxony, Germany, were investigated. Observations were conducted at two different times during the production phase. The different types of perches and their use were examined by means of photo-based behavioural observations. In total, seven different types of perches were provided. Perches were available in the slatted area as well as in the littered area. They were made of plastic, wood or metal and they were of various heights (38.0–48.0 cm above the littered area, and 0.0–15.5 cm above the raised slatted area). Complying with their natural behaviour, broiler breeders, both of the slow growing hybrid Ross Ranger and the fast growing hybrids Ross 308 and Ross 708, used all types of perches with a higher intensity during the dark-period (2.07 birds/m perch versus 0.73 birds/m in the light period). The study showed that all perch types were used. However, broiler breeders seemed to prefer perches with a height of at least 5.5 cm

Einsatz von sitzstangen in der haltung von masthühnerelterntieren und deren nutzung anhand einer fallstudie

All individuals of the species Gallus gallus, also broiler breeders, have a preference of resting on elevated areas but only few studies have focused on the resting behaviour of broiler breeders. The aim of the present study was to determine the status quo of perch use on conventional broiler breeder farms. Therefore, nine commercial broiler breeder flocks with the fast growing genetics Ross 308 and Ross 708 and the slow growing genetics Ross Ranger in Lower Saxony, Germany, were investigated. Observations were conducted at two different times during the production phase. The different types of perches and their use were examined by means of photo-based behavioural observations. In total, seven different types of perches were provided. Perches were available in the slatted area as well as in the littered area. They were made of plastic, wood or metal and they were of various heights (38.0–48.0 cm above the littered area, and 0.0–15.5 cm above the raised slatted area). Complying with their natural behaviour, broiler breeders, both of the slow growing hybrid Ross Ranger and the fast growing hybrids Ross 308 and Ross 708, used all types of perches with a higher intensity during the dark-period (2.07 birds/m perch versus 0.73 birds/m in the light period). The study showed that all perch types were used. However, broiler breeders seemed to prefer perches with a height of at least 5.5 cm.</p