E. M. Campos

Aversão alimentar condicionada no controle de surtos de intoxicações por Ipomoea carnea subsp. fistulosa e Turbina cordata em caprinos

Conditioned food aversion is used to train livestock to avoid the ingestion of toxic plants. This technique was used to control Turbina cordata poisoning in goats in one farm, and to control Ipomoea carnea subsp. fistulosa poisoning in another farm. The goats were penned at night and the next morning the green plants were offered for 10 minutes. Goats that ingested any amount of the plant were treated through a gastric tube with 175mg of LiCl/kg body weight. In the flock in which the poisoning by T. cordata was occurring, the goats were averted every two months during the period that the plant was found in the pastures. During the experiment, from December 2009 to April 2011, new cases of poisoning were not observed, and there was a progressive decrease in the number of goats that ingested the plant and were averted. In the farm where I. carnea poisoning was occurring, most of the goats were averted in December 2010, 15-20 days before the first rains. The goats of this flock did not ingest the plant spontaneously in the field until September-October 2011, when, due to the dry season, there was a severe forage shortage, and the goats started to ingest the plant in the field. Later, despite three aversive treatments with 21 days intervals, the goats continued to ingest the plant and some animals became poisoned. In conclusion, conditioned food aversion was effective in to control intoxication by T. cordata. The technique was also effective in conditioning goats to avoid consuming I. carnea during the rainy season, but not during the dry season, with low forage availability in the field. The differences in these results seem to be due to the epidemiology of both poisonings: T. cordata is senescent and unavailable during most of the dry period, and green biomass is typically available either at the very end of the dry season, for a short period of time, and during the rainy season when there is no shortage of forage. In contrast, I. carnea grows in wet areas near water sources, and stays green during the dry period when there is a lack of other forage.

Poisoning by Ipomoea asarifolia in lambs by the ingestion of milk from ewes that ingest the plant

Two experiments, each with 10 pregnant ewes (8 treated and 2 controls) were performed to determine if nursing lambs of lactating ewes become intoxicated when the ewes ingest Ipomoea asarifolia but do not show clinical signs themselves. In the first experiment the sheep grazed I. asarifolia in the field while in the second, sheep were maintained in individual bays consuming dry I. asarifolia at 10% and 20% into their ration. In both experiments the lambs remained confined, consuming only their mothers milk. Four of 8 lambs in the grazing experiment and the 4 nursing lambs from the ewes given 20% I. asarifolia showed signs of I. asarifolia poisoning. These results confirm that the tremorgenic compound of I. asarifolia or its toxic metabolites are eliminated in milk and can intoxicate nursing lambs.

Aversão alimentar condicionada para o controle da intoxicação por Ipomoea carnea subsp. fistulosa em caprinos

Conditioned food aversion is a technique that can be used to train livestock to avoid ingestion of poisonous plants. This study tested the efficacy and durability of conditioned food aversion to eliminate goats consumption of Ipomoea carnea subsp. fistulosa. We used 14 young Moxoto goats, which were initially adapted to the consumption of the plant by offering dried I. carnea subsp. fistulosa with their concentrate diet for 30 days, and then subsequently providing green plant for another 10 days. To confirm the spontaneous consumption of the plant, the goats were allow to graze in a paddock of 510m2 where I. carnea subsp. fistulosa had been planted in an area of 30m2 (10 plants/m2). On day 42, 12 goats were offered fresh green plant individually in a pen for a few minutes, and after the consumption of any amount of the plant they were treated orally with a solution of LiCl at a dose 175mg per kg of body weight. This procedure was repeated for two more consecutive days. Thereafter, the goats were divided into two groups: Group 1 with four averted and two non-averted goats; and Group 2 with eight averted goats. To verify the efficacy and duration of aversion, both groups were introduced into the paddock with I. carnea subsp. fistulosa three days a week for two hours daily. In Group 1, with two non-averted and four averted goats, all animals started to ingest the plant after 1-6 weeks of grazing. They continually increased their consumption of the plant, but never consumed the plant exclusively. None of the goats of Group 2 goats started eating the plant during the 12 months of observation. After this period the area of the paddock planted with I. carnea subsp. fistulosa was expanded to 80 m2 and grazing time was increased to four hours per day for five days a week. At this stage all the goats in Group 1 ingested the plant in large quantities. The goats from Group 2 gradually started to eat the plant and aversion was extinguished in all animals after two months. Swainsonine concentration of I. carnea subsp. fistulosa was 0.052±0.05% (mean ±SD). It was concluded that conditioned food aversion was effective in reducing goat consumption of I. carnea subsp. fistulosa, but the duration of aversion depends on the time of grazing and amount of plant available. However, the aversion was quickly extinguished by social facilitation when averted animals grazed with non-averted animals.

Substitution of Pennisetum purpureum by Opuntia ficus-indica and Mimosa tenuiflora in the diet of lambs

Os objetivos deste estudo foram quantificar a digestibilidade aparente dos componentes da dieta e o desempenho de cordeiros alimentados com niveis crescentes de uma mistura balanceada (peso) de farelo de Opuntia ficus indicae e feno de Mimosa tenuiflora em substituicao a 0, 33 e 67% do feno Pennisetum purpureum, em uma dieta com 60% de volumoso e 40% de concentrado, formulada para um ganho de peso diario de 150 g/animal. O experimento foi conduzido na UFCG, Patos-PB, usando 18 cordeiros inteiros com (20,4±1,16) kg (peso medio±EP). O CD da MS, MO, PB, EE e dos carboidratos totais foram afetados pelos niveis da mistura (P 0,05). A inclusao da mistura afetou linear e positivamente o ganho de peso medio diario (120, 149 e 170g/animal, respectivamente para 0, 33 e 67% de substituicao do feno de P. purpureum), e o consumo de MS, MO, PB, carboidratos totais e nao fibrosos. A mistura balanceada do farelo de Opuntia ficus indica e do feno de Mimosa tenuiflora pode substituir ate 67% da fracao volumosa (P. purpureum) da dieta de cordeiros Santa Ines e melhorar o ganho de peso medio diario em 50g/animal.

Reproductive losses caused by the ingestion of Poincianella pyramidalis in sheep

&NA; Malformations have been observed in sheep and goats in the Brazilian semiarid region in areas where Poincianella pyramidalis is dominant. The objective of this trial was to determine whether Poincianella pyramidalis causes reproductive changes in pregnant sheep. Sixteen non‐pregnant sheep were mated with two rams. After confirmation of the pregnancy by ultrasonography on the 18th day after mating, pregnant sheep were randomly divided into four groups (#1, 2, 3, and 4), with four animals each. Sheep received roughage in an amount equivalent to 2% of their body weight, mixed with 0%, 10%, 20% and 40% of dried leaves of P. pyramidalis for groups 1, 2, 3 and 4, respectively. In Groups 1 and 2, all animals lambed normally. In Group 3 (20% P. pyramidalis in the roughage), one lamb was born with arthrogryposis and three sheep gave birth to premature weak lambs within 128, 132, and 133 days of gestation. In Group 4 (40% P. pyramidalis in the roughage), one sheep lambed a normal lamb; another ewe had embryonic mortality after seven days of plant consumption, and two aborted on days 103 and 144 of pregnancy. One of the aborted fetuses was normal and the other showed arthrogryposis and prognathism. These results suggest that P. pyramidalis causes embryonic deaths, abortions, and malformations in sheep. Grazing pregnant sheep in areas where this plant is dominant should be avoided, and roughage for confined pregnant females should not contain more than 10% P. pyramidalis. HighlightsMalformations and reproductive problems are common in goats and sheep in Northeastern Brazil.In this region with 18 million sheep and goats, losses due to malformations are nearly 520,000 kids and lambs.Malformations and reproductive problems are observed in goats and sheep grazing Poincianella pyramidalis.Experimentally dry P. pyramidalis caused embryonic deaths, abortion and malformations in sheep.Poincianella pyramidalis is a cause of reproductive problems in sheep in Northeastern Brazil.