Developing an oral bait for badger vaccination - Exeter Research ...

significant preference behviour only towards large baits, this could be related to requiring a
significant reward for effort spend accessing a bait, or that such baits had a larger surface area and
potentially emitted a stronger olfactory signal.
Nutritional requirements of animals change over time i.e. from juveniles to adults. It is known that
female badgers rely heavily on stored fat during gestation and the initial stage of lactation
(Domingo-Roura et al. 2001) and therefore using this knowledge to provide a time specific high fat
content bait may increase uptake rates. Future studies trialing the most palatable and preferred bait
to cubs may allow a targeted baited system towards this age cohort immediately after cub
emergence from setts. It is also worth noting that experiences early on in life are known to affect
future behaviors. For example familiarity with foods that a mother eats just before and after birth
can be translated to young through the mother’s milk. Additionally interactions with mother and
peers, combined with the consequences of food ingestion, help young animals to discriminate
among foods and influence preferences and foraging behaviour (Provenza et al., 1998). Therefore
there is an argument for a period of pre-baiting with vaccine-free baits, just before the emergence of
cubs from the sett, when they are still receiving milk from and learning foraging behaviors from their
mothers. This may result in a quicker uptake in baits containing vaccine, by cubs soon after
emergence; a highly desirable outcome. Preference of a food item is dependent on palatability;
defined as a functional integration of senses (smell, taste and texture) and post-ingestive feedbacks
(effects of nutrients on chemo-, osmo- and mechano-receptors), as influenced by an animals
physiological condition and a foods chemical characteristic (Provenza et al. 1998). Our current study
did analyses significant difference of baits with different combinations of smells and tastes, for
example some smelly baits were sweet and other un-sweet (However see table 1 for descriptive
statistics). Future bait trials may wish to investigate which combination of smells and tastes are most
preferred by badgers.
The significant differences in bait disappearance by social groups could be attributed to differences
in territory size and the amount of arable and/or pasture in each social group’s territory. Those
social groups with larger territories showed reduced attempts to move slabs to access baits and
reduced rates of bait disappearance than those with smaller territories. Larger territories may
provide access to a greater quantity of natural food resources and Fletcher et al. (1990), reported
low bait acceptance by raccoons was likely influenced by the availability of ripe wild grapes at the
time of the study. As a social groups territory size increased less baits were eaten as encountered
and more baits were eaten preferentially. With larger territories potentially providing more food
badgers may be able to be choosier. When investigating bait uptake by urban foxes, Trewhella et
al.(1991) inferred that food was not a limiting resource to these urban populations, and the
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