Since August, 2007 a callitrichid diet excluding most common allergens was implemented in Asson zoo, giving evidence that these monkeys were intolerant to their old diet. Since 2004 the thirty callitrichids were fed a gluten-free diet comprising a home-made mix of six ingredients, fruits, protein-snack and feline hypoallergenic soya croquettes. It has been suspected for years that callitrichids develop allergies and food intolerances: gluten has been pointed out, specifically as taking part in the aetiology of the Marmoset Wasting Syndrome (WMS *), but Assons collection was prone to chronic diarrhoea despite excluding gluten. Therefore the new diet set up in the zoo since 2007 excludes any food potentially containing intolerance factors (lactose, gluten), or allergens (seeds, nuts, soya, casein), and thus a great majority of industrial products and artificial aromas as well as many food complements because of their excipients). At first a home-made pulp was implemented, associated with a complement elaborated for the occasion. A probiotic/prebiotic/enzyme complex was added once a week. We changed the feline croquettes for others containing no soya. In parallel, that pulp (stripped of the callitrichids complement) was integrated into Saimiris diet, these being also, though more rarely, prone to diarrhoeas. After a 20 month follow-up of this new food plan, a second transition allowed to replace the domestic pulp by an industrial one. Indeed use of powder-based foodstuffs is a saving of time for zoo personnel. This complete diet formulated for New World Monkeys is also intended for Marmosets when associated with a food complement produced by the same supplier. Appetence and not needs directs the animals choice, so it is through balanced tests of increasingly severe restrictions in the choice of raw materials (appetence problems being added to the multitude of foodstuffs forbidden due to intolerances or allergies) that the final diet could be accepted by all those species. Other difficulties occurred, like lack of mash volume compared to ingest capacity, because of a too much concentrated foodstuff with first experiments. The new diet was accompanied from the very start of food transition (which lasted for one month) by the disappearance of digestive disorders, in spite of climatic vagaries (premature temperature drop and increased humidity mid-August 2007). Nevertheless this year an antihelminthic infestation confounded the study. Finally the diet change brought successfully results since it stopped the chronic diarrhoea. Birth rate has been kept and monkeys seems healthy, which has been indeed confirmed by blood samples revealing that unlike two years ago, callitrichids present no more signs of anaemia. Moreover, the recent industrial version, being ready to use only by adding water, is precisely balanced and easy to use, a real improvement compared to the old diet. Last but not least food supply is well known, since animals consume the mash entirely. This new diet highlights that certain callitrichids are sensitive to other allergens than gluten: the next step is to examine which of these allergens is(are) the root cause(s). In the meantime, a ration stripped of the most common allergens, and not only gluten, seems to be the best solution.
Author(s): Morgane Byrne