RIVERO, B. R. C.; RIVERO, Beatriz Riet Correa.
Resumen:
This thesis contains three articles which are divided into chapters. The first chapter is a
review covering various aspects for the control of gastrointestinal nematodes (GIN) of goats,
including: 1) the differences between goats and sheep to GIN infections; 2) important
epidemiological aspects to consider in the control; and 3) technologies to be used for
integrated control of GIN and anthelmintic resistance. The second chapter describes the
strategies for gastrointestinal parasites control applied, from July 2010 to November 2012, in
eight dairy goat farms, located in the semiarid region of the state of Paraiba, Northeastern
Brazil. Monthly visits were made to the farms for conducting clinical evaluation of the flocks
and to collect fecal samples of 10% of the goats to perform parasitological fecal egg count
(FEC). Furthermore, in herds treated with anti-helminthic, when the drug efficiency
decreased, resistance tests were performed to choice another anti-helminthic. After 20 months
of monitoring with OPG, two farms were selected to control GIN by FAMACHA © during
eight months. Throughout the study the farmers who held control based on OPG, treated their
flocks 3.1±0.7 times a year. During the first year the number of treatments during the rainy
period (2.3±1.1) was significantly higher (P <0, 05) than during the dry period (1.5±0.8). In
the second and third year it was not possible to perform this comparison due to the long
period of drought. In the farms in which FAMACHA © was used, 41.2% of the animals were
no treated, 26.1% were treated once, and 32.5% were treated twice or more times, with an
average 1.2±1.5 treatment/animal. At the same period, in the farms controlled by FEC the
mean was 0.8 treatment per goat. Multiple anti-helminthic resistance was observed in the
seven farms in which the resistance test was performed. However, no outbreak of
gastrointestinal parasites were observed during the period. The third chapter describes a
multidisciplinary study in eight dairy goat farms from the semiarid of Paraíba performed for a
two years period with the aim to identify the main limiting factors for milk production and to
propose and evaluate intervention strategies. In the first year, seven farms had forage
deficiency during the dry season, but only two during the rainy season. In the second year,
after technical advertisement, six farms still had forage deficiency during the dry season and
only two during the rainy season. The average milk production per goat was 1.19 liters.
Zootechnical bookkeeping was originally not practiced in any farm at the start of the study,
but it was gradually and partially established. The main diseases recorded were caseous
lymphadenitis, subclinical mastitis, keratoconjunctivitis and contagious ecthyma. The
prevalence of subclinical mastitis, caseous lymphadenitis and gastrointestinal parasitoses were
reduced after technical assistance. After analyzing the data, it can be concluded that a
continuous and multidisciplinary technical assistance may minimize the factors limiting dairy goat production. The study showed that farmers accept the new technologies if they are
appropriate to the production systems and are gradually implemented.
