Garrano. The primitive rebel from the North
The autochthonous Garrano breed,
beyond its relevance in historical and cultural level, is one important
reservoir of national genetic variability. Since 1943 a group have lived freely
in Peneda-Gerês National Park. A study made from November 2012 to April of 2013
shows that this animals are very parasitized, but they don’t present a
concerning inbreeding level. There are good reasons to look to the future of
this valuable biologic resource.
One of the species that stands out the most in
Peneda-Gerês National Park (PGNP) is the Garrano pony, one of the three
Portuguese horse breeds (alongside the Lusitano and the Sorraia). They are
small individuals with broad shoulders, a thick neck and abundant manes and fur
(Andrade, 1938). They have been in the Iberian Peninsula since the Quaternary
period of geological history (Andrade,1938; Oom, 1992; Gomes, 1996). This makes
the Garrano the primitive rebel from the North.
During the application process of the Garrano as
national heritage, intending to avoid its extinction, a group of students from
Colégio Valsassina developed a study on the Garranos of PGNP, from November
2012 to April of 2013.
The results reveal a high level of parasitism, with a
100% level of strongylids prevalence, in fact, these data were already verified
by Gomes (1996) in 1994-95, when it was registered a higher average level of
eggs per gram of faeces.
Despite the facts, it will be much difficult to
reduce the levels of parasitism. On one hand, the animals live freely. On the
other hand, many of the used pastures are probably contaminated, which
facilitates “recontamination”. Notwithstanding, it’s considered important to
develop a monitoring program of parasitism level. In spite of not deworming the
animals, the information is always important (Branco and Osório, 2012).
The inbreeding level of the group was studied too,
using the Pedigree Viewer program. The data shows that the age average of the
population is a little higher than the adult age (6,62 years old) and it seems
that there are not problems referring to the inbreeding possibility between
individuals. Considering “1” (certain) as the maximum probability of occurrence
of an inbreeding situation and “0” (impossibility) as the minimum probability,
it was verified a maximum of 0,1875. The modal result was 0. Therefore, it is
not foreseeable that this factor would jeopardize the population and the
progeny viability of the current generation. However, the low number of
individuals could compromise the future of the population, once its variability
could become diminished. To avoid this situation, it’s advised a recurrent
introduction of new individuals “alien to” the group in order to keep an
acceptable level of variability (Oom, 1978).
According to António Rebelo, a technician of the PGNP
responsible for the monitoring the Garranos in the field, the current group is
only composed by 15 animals. Everything point out a register of an effective
population regression in the last years, specifically, comparing with the
situation of 1994-96, described by Gomes (1996). However, the fact of existing
five males (ally to a low level of inbreeding in the population) could be
potential a positive factor for the effective raise of the population in short
or medium term.
To Maria do Mar Oom, from Faculty of Science of the University of Lisbon and ambassador of
the breed in the application to national heritage, the Garrano, beyond its
relevance in historical and cultural level, is one important reservoir of
national genetic variability. The developed efforts with the aim of
conservation and support of the breeders are fundamental, which ensure a
sustained use of this genetic resource from the mountain rural environment of
the Portugal North, where they have been since the Paleolithic.
From the legal framework, the national park continues
presenting conditions to preserve this important biological resource,
integrating genetic, environmental, social and cultural perspective.
Ana Catarina
Caçote, Gonçalo Pereira, Joana Duarte. 12º1A
Agradecimentos:
Este trabalho não seria possível sem a preciosa colaboração da
Doutora Maria do Mar Oom, da
Faculdade de Ciências da Universidade de Lisboa e do técnico do Parque Nacional
da Peneda-Gerês, António Rebelo, por todo o tempo, ajuda e disponibilidade,
essenciais para a realização do nosso projeto. Gostaríamos também de agradecer
ao Parque Nacional da Peneda-Gerês pela ajuda disponibilizada.
