Navegando por Autor "COOK, Daniel"

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Acesso aberto (Open Access)
Conditioned food aversion to control poisoning by Ipomoea carnea subsp. fistulosa in goats
(2014-07) OLIVEIRA JÚNIOR, Carlos Alberto de; CORREA, Gabriela Riet; TAVARES, Carla; SOUZA, Elda Ely Gomes de; CERQUEIRA, Valíria Duarte; PFISTER, James A.; COOK, Daniel; CORREA, Franklin Riet
Ipomoea carnea is a toxic plant often ingested by livestock in Brazil. Three experiments were conducted to determine if conditioned food aversion was effective in reducing goats' consumption of I. carnea. In the first experiment, 10 mildly intoxicated goats that had been eating I. carnea were averted using LiCl (175 to 200mg kg-1 body weight). These intoxicated goats did not develop an aversion to I. carnea, demonstrating that the technique is not effective in goats that are already accustomed to consuming the plant. In the second experiment, 14 naïve goats were placed in a pasture with I. carnea, and averted after they ingested the plant. In this group the aversion persisted until the end of the experiment, 2 years and 8 months after the initial aversion. In another experiment, 20 goats were placed in a pasture with I. carnea, and after consuming the plant were averted with LiCl. The averted goats were transferred to Marajo Island and periodically observed over a 2 year period at 2-3 month intervals to determine if they were still averted. The averted goats did not ingest the plant while grazing in the pasture, whereas in 6 neighboring goat farms the prevalence of intoxication from I. carnea poisoning was estimated to be about 40%. These results demonstrated the efficacy of conditioned food aversion to avoid ingestion of I. carnea in formerly naïve goats that had only recently begun to ingest the plant.
Acesso aberto (Open Access)
Conditioned food aversion to Ipomoea carnea var. fistulosa induced by Baccharis coridifolia in goats
(2013-08) ADRIEN DELGADO, María de Lourdes; CORREA, Gabriela Riet; OLIVEIRA JÚNIOR, Carlos Alberto de; PFISTER, James A.; COOK, Daniel; SOUZA, Elda Ely Gomes de; CORREA, Franklin Riet; SCHILD, Ana Lucia
Baccharis coridifolia is a plant that induces strong conditioned food aversion in ruminants. This research aimed to induce a conditioned food aversion to Ipomoea carnea var. fistulosa in goats, using B. coridifolia as an aversive agent, and to compare the aversion induced by this plant with the aversion induced by lithium chloride (LiCl). Thirteen goats were allotted into two groups: Group 1 with six goats was averted with 175mg/kg of body weight of LiCl and Group 2 with seven goats was averted with 0,25g/kg of bw of dried B. coridifolia. All goats were averted on day 1 after the ingestion of I. carnea. The aversion procedure with LiCl or B. coridifolia in goats from Groups 1 and 2, respectively, was repeated in those goats that again consumed the plant during tests on days 2, 3, and 7. The goats of both groups were challenged in pens on 23 and 38 days after the last day of aversion and challenged in the pasture on days 11, 15, 18, 20, 22, 25, 27 and 29 after the last day of aversion. After this period goats were challenged every 15 days on pasture until the 330º day after the last day of aversion (7th day). Two goats from Group 1 ingested I. carnea on the first day of the pasture challenge, 4 days after the last day of aversive conditioning in the pen. In addition, another goat in Group 1 started to consume the plant on day 18, and other two goats ate it on day 20. One goat in Group 1 that had never eaten I. carnea died on day 155. One goat from Group 2 started to ingest I. carnea on the first day of the pasture challenge, and a second goat started to consume this plant on day 182. At the end of the experiment, on day 330, the other five goats averted with B. coridifolia remained averted. These results suggest that B. coridifolia or an active compound from the plant could be used to induce aversion to toxic plants. Using B. coridifolia would be cheaper and, particularly in flocks with large number of animals, possibly easier than using LiCl, which requires the use of oral gavage and qualified personnel for its implementation.
Acesso aberto (Open Access)
Feeding preferences of experienced and naïve goats and sheep for the toxic plant Ipomoea carnea subsp. fistulosa
(Universidade Federal do Pará, 2015-09) OLIVEIRA JÚNIOR, Carlos Alberto de; CORREA, Gabriela Riet; LIMA, Everton Ferreira; LEITE, Danilo Maia; PFISTER, James A.; COOK, Daniel; CORREA, Franklin Riet
Ipomoea carnea is a toxic plant that grazing goats and cattle may learn to ingest with repeated exposure. The objective of this study was to evaluate the feeding preferences of experienced and non-experienced (naïve) goats and sheep for I. carnea. The study used 3 groups of 5 goats (Group 1, experienced that were previously poisoned by the plant; group 2, naïve; Group 3, experienced eaters, composed of animals adapted to eat the fresh plant) and 2 groups of sheep (group 4, experienced that were previously poisoned by the plant; and group 5, naïve). For the test, the animals were placed daily for 10 minutes and 4 days in a rectangular stall (5x7m) with 4 feeders, each with 200g of a different food (Ipomoea carnea, commercial concentrate food, recently harvested green grass (mainly Brachiaria spp.), and Cynodon dactylonhay. The intake of concentrate food was significantly higher (P<0.05) than the consumption of green grass, hay and I. carnea. In a second 4 day trial, in which the commercial concentrate food was replaced by freshly harvested Amorimia septentrionalis, the ingestion of green grass (Brachiaria spp.) was significantly higher (P<0.05) than the consumption of other foods. In both trials there was no significant difference in food consumption between eaters and naïve animals. The results suggest that experienced or naïve sheep and goats do not prefer I. carnea when it is offered with other foods or forages, suggesting that animals will avoid the plant and not become poisoned if other food options are available.