Lucas Maciel Cunha

A novel Rickettsia infecting Amblyomma dubitatum ticks in Brazil

A total of 130 adult free-living ticks of Amblyomma cajennense and 9 free-living Amblyomma dubitatum were collected in the surroundings of the Pampulha Lake, within Belo Horizonte city, state of Minas Gerais, south-eastern Brazil. Each adult tick was tested for rickettsial infection by PCR protocols targeting the rickettsial genes gltA, htrA, and ompA. All the 130 A. cajennense ticks were negative by PCR. In contrast, all 9 A. dubitatum ticks were shown to contain rickettsial DNA. PCR products were sequenced, generating identical sequences for each gene among the 9 ticks, which were shown to contain a novel agent, here designated as Rickettsia sp. strain Pampulha. Phylogenetic analyses inferred from the 3 rickettsial genes (gltA, htrA, ompA) showed that Rickettsia sp. strain Pampulha segregated in the same cluster with R. tamurae, R. monacensis, and several other unclassified rickettsial strains; however, strain Pampulha is a unique Rickettsia strain for the New World, since its closest relatives, according to 3 genes (gltA, htrA, and ompA), are all from the Old World. Because A. dubitatum eventually bites humans, further studies are necessary to determine the potential pathogenicity of Rickettsia sp. strain Pampulha to humans.

Impacto do hábito de jantar sobre o perfil dietético de pacientes em hemodiálise

INTRODUCTION To assess the effects of the habit of having evening dinner on the dietary macro- and micronutrient profile of chronic kidney failure patients on hemodialysis. METHODS Cross-sectional study carried out at a dialysis clinic at the city of Belo Horizonte, state of Minas Gerais. The study comprised 90 patients undergoing hemodialysis. Personal, clinical, and dietary (three-day food record) data were collected. The habit of having dinner was considered as having a complete evening meal, and the lack of that habit was considered as not having it or replacing it by a fast meal. The amounts of nutrient intake were estimated in the specific software Dietwin®. RESULTS The carbohydrate, thiamine, riboflavin, ascorbic acid, calcium, and selenium intake values showed no difference between the group having a complete evening meal and that not having it (p > 0.05). Both groups did not differ in the following: body mass index, and energy, protein, lipid, niacin, pantothenic acid, pyridoxine, folic acid, cobalamin, potassium, phosphorus, zinc, and magnesium intake values (p < 0.05). Regarding nutrient adequacy, the complete evening meal group performed better than the other group, except for carbohydrates, lipids, pantothenic acid, ascorbic acid, potassium, calcium, and zinc (p < 0.05). None of the patients showed the adequate pyridoxine, folic acid, and selenium intake values. Few patients in both groups showed adequate energy, pantothenic acid, and zinc intake values. CONCLUSION The habit of having a complete evening meal influenced positively the micro and macronutrient intakes in chronic kidney failure patients on hemodialysis.

Mites affecting hen egg production: some considerations for Brazilian farms

The poultry industry is characterized for its constant search for productivity and profitability, which are based on flock health status. Brazilian Commercial laying hens (Gallus gallus domesticus) have been impacted significantly by mite infestations. This review aims to compile the literature on the occurrence, economic losses, biology, epidemiology and control of mite species considered important for the Brazilian laying poultry industry. The national experience was compared with practices of other countries and a scarcity of studies on this subject in Brazil was evident. The poultry industry has prioritized the use of pesticides to control infestations with little regard for the adverse effects. In this context, the integrated control programs using several strategies simultaneously constitute the best alternative to mite control. Integrated control programs involve measures of chemical, physical and biological nature, as well as attention to cultural aspects. However, studies should be performed aiming at the development of new control methods, evaluating the adequacy of practices developed in other countries to the national reality.

Amblyomma rotundatum (Koch, 1844) (Acari: Ixodidae) two-host life-cycle on Viperidae snakes.

Amblyomma rotundatum is an ixodid tick that infests ectothermic animals and reproduces exclusively by parthenogenesis. This tick has been frequently reported to infest reptiles and amphibians, under natural conditions and sometimes in captivity. It was described in Brazil and several other countries of South, Central and North America. Although many studies have reported aspects of its biology, none of them has used regularly either ophidian as hosts, or controlled temperature, humidity and luminosity for parasitic stages. The objective of this experiment was to study the life cycle of A. rotundatum feeding on Viperidae snakes under room controlled conditions at 27 ± 1 °C temperature, 85 ± 10% relative humidity and 12:12 hours photoperiod for parasitic stages, and under B.O.D incubator conditions at 27 ± 1 °C temperature, 85 ± 10% relative humidity and scotophase for non-parasitic stages. The total duration of the life cycle ranged from 56 to 163 days (mean of 105 days). Two-host life cycle was observed for most of the ixodid population studied.

Percepção de criadores de Gir a respeito da otite parasitária de bovinos em três estados brasileiros, 2009

This study aimed to know the perception of Gir cattle breeders and farm employees about parasitic otitis and practices regarding methods of treatment and control. A questionnaire was applied on specific topics about the disease. The results showed that the otitis occurred in 25 (89.3%) of the 28 farms studied, where the main etiologic agents were the nematodes Rhabditis spp. The majority of the farmers regarded the disease as a serious problem, mainly in cattle older than eight years of age. About half of the respondents did not observe a correlation between season and prevalence of the otitis; however, 30.8% reported an increase of its incidence during the rainy season. In addition to various methods and products for the rhabditiosis treatment, a lack of standardized preventive or curative protocols was found, suggesting insufficient knowledge about control of the disease.

QUILL MITES IN BRAZILIAN PSITTACINE BIRDS (AVES: PSITTACIFORMES)

The primary and secondary feathers of 170 Brazilian psittacine birds (Aves: Psittaciformes) were examined in order to identify feather quill mite fauna. Birds were held captive in two locations in the state of Minas Gerais (MG), and two in the state of Espirito Santo (ES). The quills were cut longitudinally and were examined under optical microscopy. The genus of quill mites most frequently found was Paralgopsis (Astigmata: Pyrogliphidae), followed by Cystoidosoma (Astigmata: Syringobiidae). Astigmata: Syringophilidae mites were sporadically observed. After analyzing the data using logistic regression models, it was determined that there was higher infestation risk for psittacines in ES state, as compared with those in MG, and a significant increase in risk depending on the psittacine host species. However, the location of captivity did not have a significant effect. Lesions were observed in infested feathers. Cystoidosoma sp. and Paralgopsis sp. were always observed together, with parts of Paralgopsis found inside Cystoidosoma sp., suggesting thanatochresis or predation.

Hepatozoon ssp. (Apicomplexa: Hepatozoidae) Infection and Selected Hematological Values of the Neotropical Rattlesnake, Crotalus durissus collilineatus (Linnaeus, 1758) (Serpentes: Viperidae), from Brazil

Abstract:  This study aims to establish the hematological values of Crotalus durissus collilineatus snakes captured in Brazil as well as to verify the effects of hematozoan infection on these snakes. Eighty-three blood samples were drawn from C. d. collilineatus specimens for analysis. The sample set was composed of 30 males and 30 females, recently caught from the wild, and 11 males and 12 females bred in captivity. Blood samples were used to determine red blood cell counts, white blood cell counts, thrombocyte counts, hematocrit values, hemoglobin concentration, and total plasma protein. Blood smears were used to diagnose Hepatozoon spp. infection and to calculate the parasitic load in the sample as well as the percentage of immature red cells. Results obtained for the wild-caught animals, with and without parasites, were compared among themselves and with the values obtained for the captive-bred animals. Hematological values for C. durissus were established. Wild-caught snakes had an infection rate of 38.3%, while no Hepatozoon sp. infection was detected in the captive-bred animals. The snakes which were not infected by the Hepatozoon sp. exhibited average weight, length, and weight–length ratios higher than those of the infected animals. An increase in immature red cells was noted in the Hepatozoon-infected snakes.

Epidemiology of Megninia spp. in laying flocks from the State of Minas Gerais, Brazil

Aspects related to the epidemiology of Megninia ginglymura were studied, in order to determine predisposing factors for the occurrence in layer chicken houses of commercial farms in the State of Minas Gerais, Brazil. An observational, cross-sectional, analytical survey was conducted for identifying major risks or protection factors for infestations. Four hundred thirty-one houses located in forty-three farms were visited in 2012. Regarding the farms, 17 (39.53%) had chickens infested by M. ginglymura and 1 (2.32%) presented Megninia cubitalis. The epidemiological aspects of the occurrence of M. ginglymura were investigated using multiple logistic regression models. The chicken house organization was an important protection factor involved in the occurrence of M. ginglymura (odds ratio [OR] = 0.85). The presence of subsistence breedings of poultry within the premises or at the proximity of a farm was characterized as a risk factor for the occurrence of infestations (OR = 3.92). The use of mineral oil (OR = 0.16) was considered protective against new infestations. Some regions of the state were characterized by a higher risk for mite infestation than others.

Laminosioptes cysticola in free-range chickens in Minas Gerais, Brazil

The subcutaneous acarid parasite Laminosioptes cysticola, the fowl cyst mite, has been found for a number of years in free-range chickens of peri-urban and rural Minas Gerais, forming collagen cysts which may be subsequently calcified after the parasites death. The role of free-range chickens as hosts and the possible risk of food-borne human allergy, as a result of its consumption in feed, are considered.

Epidemiological Characterization and Risk Assessment Associated with the Presence of Diptera Order in Laying Poultry Farms

Background: Health aspects of flocks of laying chickens, such as the occurrence of infestations by parasites and poultry pests, influence significantly the productivity indicators. In recent years, Brazilian poultry has gone through a scientific and technological evolution which resulted in high density poultry hens in the laying sheds and an increase of the occurrence of ectoparasites such as Diptera. The presence of these flies have caused negative impacts for poultry farming, since these may be responsible for the increase of stress and disease emergence and, in addition, reduction of productivity. In this context, the control of synanthropic Diptera is one of the challenges of the poultry farmers and professionals of this area. This study was carried to assess and characterize the risks for the presence of flies in chicken houses of laying farms in the state of Minas Gerais. Materials, Methods & Results: Was used a secondary database and adapted for this study, with information from 402 chicken houses of 42 laying hens commercial properties. The variables used to compose the correspondence model were selected through chi-square tests (P ≤ 0.05). A risk index was built to the presence of flies from variables considered as risk factors for these ectoparasites. In addition, a study of the spatial analysis was carried to evaluate the intensity of chicken houses of poultry farms with the presence of flies. For this, a Kernel map was produced using the QGIZ 2.18.1 software, georreferencing the regions of state of Minas Gerais that have these ectoparasites. It was observed the presence of flies in 253 chicken houses evaluated, which corresponds to a frequency of 62.9%, with the most present flies were Chrysomya spp. 37.3%, M. domestica 34.3%, Fannia spp. 16% and Stomoxys spp. 14%. The graph of the correspondence analysis produced for the epidemiological characterization of the presence of flies presented an accumulated chi-square value of 56.05%. There was an association of the risk index with removal interval and the humidity of the manure and with the type of installation of chicken houses. Farms with chicken houses that create their birds on the ground present a lower risk for the presence of Diptera. In addition, when the removal of the manure is performed manually and is not done periodically, the presence of flies in the chicken houses is observed. It was verified that clusters located in the messoregion south/southwest of Minas Gerais and between the west and metropolitan mesoregion of Belo Horizonte with chicken houses that have the presence of flies. Discussion: The accumulation and permanence of manure can occur in less technical farms that have laying hens kept in confinement with high densities. In the case of Diptera, the greater the interval of removal of the manure below cages, the greater the risk for their presence, combined with the high densities of the birds that contribute to a faster accumulation of manure. The humidity of the manure is another important factor for the development of flies. The risk is high when chicken feces are liquefied, due to the fact that larvaes of flies need a moist substrate for survival. These results provide knowledge about the epidemiology of flies, in addition to demonstrate the profile of laying farms in the state of Minas Gerais. The implementation of certain management measures and the investment in technification of the chicken houses could reduce the risks of possible infestations in the flocks, besides the negative effects resulting from this ectoparasitism.