No abstract

This study aimed to clarify the type of photosensitization induced by C. serpens and to verify if the plant remains toxic after being collected and stored. Eight crossbred sheep, aged between 6 and 36 months, were divided into three groups (G1 to G3). Over 30 days, daily, G1 received an exclusive diet of C. serpens, and G2 and G3 received 10 g/kg/BW and 20 g/kg/BW, respectively. Two other sheep were used as controls (CG). Before administration, the plant had been harvested every 15 days. Liver biopsies and blood samples were taken from all sheep on day zero and weekly. All sheep that received the plant developed clinical signs of photosensitization, and no changes were observed in the serum activities of AST and GGT. On day 30, all sheep except Ov1 from G1 and Ov7 were euthanized and necropsied. All sheep that received the plant developed clinical signs. Macroscopic or histologic lesions were not observed in the liver. Ov 1 recovered 13 days after the end of ingestion. These results demonstrated that C. serpens causes primary photosensitization. It is advisable to avoid grazing on pastures invaded by the plant or to remove them from the pastures immediately after observing the first signs.

Poisoning by Prosopis juliflora (mesquite) leads to neurological signs, cachexia and death, mainly in cattle and goats. Although the uncontrolled spread of mesquite in the Caatinga biome (biological invasion), which alters the epidemiological conditions of intoxication by this plant, has been proved for approximately 20 years, strategies for its control and prophylaxis still remain out of date. These new epidemiological conditions have allowed the uncontrolled consumption of large amounts of in natura mesquite pods by ruminants for long periods in invaded pastures, thus resulting in increased history of poisoning. This study aimed to describe the new epidemiological aspects of P. juliflora poisoning in cattle and goats, 78 years after the introduction of this plant in the country, with emphasis on its degree of invasion, and to update the control and prophylaxis measures of this intoxication and the mapping of areas of outbreak occurrence in the semiarid region of the state of Bahia, Brazil. Seven outbreaks of natural mesquite poisoning, two in goats (OB 1 and OB 2) and five in cattle (OB 3, OB 4, OB 5, OB 6, and OB 7), were studied in loco in the municipalities of Juazeiro, Iaçu, Tucano, Santa Teresinha, Barra do Mendes, Barra and Tabocas do Brejo Velho. In the studied outbreaks, clinical-epidemiological (OB 1 to OB 7) and histopathological (OB 1, OB 2, OB 3, and OB 5) findings were compatible with mesquite poisoning, and this was the first anatomopathological proof of poisoning by this plant in this state. In addition, in the state of Bahia, disease occurs in an area approximately three times larger than previously known. On the farms investigated, mesquite introduction occurred between 1980 and 2005, through the single planting of an average of 33 seedlings. Since then, propagation of this plant has occurred progressively, with gradual invasion of native pastures, which enabled the evaluation of plant spread (biological invasion) on these farms 15 (OB 2), 25 (OB 7), 30 (OB 5 and OB 6), 35 (OB 3) and 40 (OB 1 and OB 4) years after its introduction. Historical information on the introduction and spread of mesquite in the state of Bahia had never been analyzed. In 2020, a degree of mesquite invasion an average 59.57% was verified in the pastures of the seven farms where the outbreaks occurred. The great biological invasion capacity of this plant drew attention, especially in OB 5. The high degree of mesquite invasion observed (new epidemiological conditions) justifies the increased number of cases of poisoning observed in this study. Processing of P. juliflora pods (grinding) was not carried out on any farm (OB 1 to OB 7), and ruminants uncontrollably consumed large amounts of pods in natura for long periods in invaded pastures, which allowed massive dispersal of seeds through feces over decades. The main factors responsible for the gradual invasion of pastures by mesquite over time were absence of crop management plans (silvicultural treatments) and lack of knowledge by producers on disease etiology. Given the new epidemiological conditions, restriction of animal access to in natura pods in pastures and supply of mesquite bran are crucial for the control and prophylaxis of this poisoning, as consumption of in natura pods had a strong correlation with the high degree of invasion in the pastures where the seven outbreaks occurred. Additionally, although the commercialization of pods and exploitation of wood of mesquite trees can provide livestock farmers with extra income - being the correct management for areas invaded by this plant, such practice is either not yet known or not carried out technically or satisfactorily by farmers. In addition to being a threat to the Caatinga’s biodiversity, the increasing invasion of semiarid areas by mesquite 78 years after its introduction in the Northeast region of Brazil, is a risk for herds, since the occurrence of poisoning outbreaks may become more frequent. Therefore, it is highly advisable that effective measures be adopted to control P. juliflora propagation.

The objective of this study was to describe for the first time the clinical-epidemiological, laboratory and pathological aspects of different forms of enzootic ataxia in goats and lambs in the state of Bahia, as well as to propose an emergency oral treatment with copper sulfate in an individualized way for neonates. Three outbreaks of enzootic ataxia were studied. The history, clinical signs and epidemiological data were obtained from the owners and checked during the visits. The first outbreak (FO) occurred in 2013 in a property located in the municipality of Itaberaba and affected a herd composed of 90 goats and 130 sheep. The second outbreak (SO) occurred in 2014 in the municipality of Santa Luz and affected a herd of 90 goats and 110 sheep. The third outbreak (TO) occurred in 2018, in a property located in the same municipality of the SO, being the herd constituted by 80 sheep. Samples of blood were collected from all goats and sheep treated for serum copper dosage. Nine animals (five goats and four sheep) that presented a more severe clinical picture and unfavorable prognosis were necropsied for diagnostic confirmation. During the necropsy of the FO, SO and TO animals, liver samples were collected for copper dosage as well as fragments of several organs for histopathology. At the site where the SO occurred, samples of soil and the main forages where the animals were kept were collected to determine copper, iron, molybdenum, sulfur and zinc contents. The clinical and histopathological findings in the three outbreaks studied were characteristic of enzootic ataxia. In the outbreaks studied, the frequency of enzootic ataxia was higher in goats (52) than in lambs (39). In the goats the mean values of serum copper (0.05mg/kg) and hepatic (2.48mg/kg) of the FO and SO were well below their respective reference values, 12 times lower than serum levels and eight times lower in relation to liver contents. On the other hand, TO sheep presented mean values of serum copper (0.015mg/kg) reduced by 40 times. The levels of iron and sulfur were high in the fodder of the property where the SO occurred, already in the soil, iron levels were high and copper levels were reduced. The treatment tested in neonates and lambs with two doses of copper sulphate solution orally at a dose of 20mg/kg for sheep and 35mg/kg for goats during the first and second week of life was effective in prevention of enzootic ataxia in neonates and can be used for emergency control of the disease. The occurrence of enzootic ataxia (congenital and late form) in goats and sheep was first reported in Bahia. It is also worth noting that this disease caused by copper deficiency has caused great damage to the breeders of small ruminants, mainly due to the high mortality of the animals affected.