Concentrations of polycyclic aromatic hydrocarbons (PAHs) in liver samples of green turtles Chelonia mydas stranded in the Potiguar Basin, northeastern Brazil.

Sea turtles are affected by pollutants worldwide, and the polycyclic aromatic hydrocarbons (PAHs) have been detected in different types of samples and at high levels in some cases. The present study brings concentrations of 37 PAHs in liver samples of 17 green turtles Chelonia mydas stranded in northeastern Brazil [four with cutaneous tumors of fibropapillomatosis (FP), being classified as FP+]. Six PAHs were detected in 100% of the liver samples, and all alkylated PAHs were frequently quantified. High levels of phenanthrene (771.20 and 794.43 ng g-1 d.w.) and fluorene (1882.36 ng g-1 d.w.) were found in three females FP- (without FP cutaneous tumors). On the other hand, one green turtle FP+ had the higher level of naphthalene (531.70 ng g-1 d.w.), compound detected in 82.35 % of the samples. Our study brings additional baseline of organic pollutants in green turtles, improving knowledge on bioaccumulation of these compounds in sea turtles.

Epidemiological Situation of Glanders in the State of Pará, Brazil.

Glanders is an anthropozoonosis caused by the bacteria Burkholderia mallei, affecting mainly equids. It has been eradicated in North America, Australia, and Western Europe, but continues to occur sporadically in countries in Asia, Africa, the Middle East, and South America. Its notification is mandatory by the World Organization for Animal Health. After 30 years, the disease reappeared in Brazil in 1999 and, thereafter, 1,413 outbreaks have been reported. However, the epidemiological situation of the disease in the country is not adequately known. Thus, 2718 animals from 654 properties in the state of Pará were randomly selected by sampling and examined using a serial protocol with Complement Fixation and Western Blot serological tests. The prevalence of properties infected with glanders in the state was estimated at 1.68% [0.84; 3.33] and of seropositive animals at 0.50% [0.27; 0.94]. The introduction of animals was individualized as a risk factor for disease introduction in the properties (OR = 5.9 [1.4; 25.5]). Despite the low prevalence of infected properties and seropositive animals, the state must review actions to fight the disease, considering that the strategies implemented have not affected the endemic balance of the disease. This process must involve all public and private agents interested in the topic.

Apparent prevalence and risk factors for bovine tuberculosis in the state of Paraná, Brazil: an assessment after 18 years since the beginning of the Brazilian program.

Bovine tuberculosis (bTB) impacts considerably animal production and one health worldwide. To describe the prevalence, risk factors, and spatial pattern of the disease in the state of Paraná, Brazil, a cross-sectional study was conducted from September 2018 to February 2019. The area was divided into seven regions. Within each region, farms were randomly selected, and a predetermined number of cows was selected and tested by a comparative cervical tuberculin test. 17,210 animals were tested across 1757 farms. Herd prevalence of bTB-infected herds in Paraná was 2.5% [1.87-3.00%]. It has varied from 0.8 to 3.98% among seven regions, with clustering being detected in the west, central, and northeast areas. Animal prevalence was 0.35% [0.21-0.59%] and has varied from 0.08 to 0.6% among the pre-set regions. No major shifts in the prevalence of bTB were detected since 2007. Large-sized herds, dairy production, and feeding with whey were detected to be correlated with the presence of bTB. Exclusively among dairy herds, veterinary assistance from cooperatives, possession of self-owned equipment to cool milk, and feeding with whey were correlated with the disease. Considering these results, it is recommended that the state of Paraná seek to implement a surveillance system for the detection of bTB-infected herds transforming them into free ones, if possible, incorporating elements of risk-based surveillance. Health education is also recommended to inform farmers about the risks of introducing animals without testing and of feeding raw whey to calves.

Network analysis of pig movements in Ecuador: Strengthening surveillance of classical swine fever.

The analysis of domestic pig movements has become useful to understand the disease spread patterns and epidemiology, which facilitates the development of more effective animal diseases control strategies. The aim of this work was to analyse the static and spatial characteristics of the pig network, to identify its trading communities and to study the contribution of the network to the transmission of classical swine fever. In this regard, we used the pig movement records from the National Veterinary Service of Ecuador (2017-2019), using social network analysis and spatial analysis to construct a network with registered premises as nodes and their movements as edges. Furthermore, we also created a network of parishes as its nodes by aggregating their premises movements as edges. The annual network metrics showed an average diameter of 20.33, a number of neighbours of 2.61, a shortest path length of 4.39 and a clustering coefficient of 0.38 (small-world structure). The most frequent movements were to or from markets (55%). Backyard producers made up 89% of the network premises, and the top 2% of parishes (highest degree) contributed to 50% of the movements. The highest frequencies of movements between parishes were in the centre of the country, while the highest frequency of movements to abattoirs was in the south-west. Finally, the pattern of classical swine fever (CSF) disease outbreaks within the Ecuador network was likely the result of network transmission processes. In conclusion, our results represented the first exploratory analysis of domestic pig movements at premise and parish levels. The surveillance system could consider these results to improve its procedures and update the disease control and management policy, and allow the implementation of targeted or risk-based surveillance.

Seroprevalence and risk factors for bovine brucellosis in the state of Paraná, Brazil: an analysis after 18 years of ongoing control measures.

Seroprevalence and risk factors of bovine brucellosis (Brucella abortus) in herds and cattle were estimated by a cross-sectional study in the state of Paraná, Brazil. The state was divided into seven regions and a random, two-stage sampling was performed on properties and cattle from each region between 2018 and 2019. Serum samples were collected from 11,592 cows over 24 months from 1,757 properties and a questionnaire was applied to identify potential risk factors. As recommended by the National Program for the Control and Eradication of Animal Brucellosis and Tuberculosis (PNCEBT), serological testing for the detection of anti-Brucella antibodies included the buffered plate agglutination test (screening test) and the fluorescence polarization assay (confirmatory test). The seroprevalence of bovine brucellosis on properties and in cattle was 4.87% (95% confidence interval [CI]: 3.98-5.93%) and 2.24% (95% CI: 1.47-3.41%), respectively. Multiple logistic regression analysis identified larger herd size and failure to test for brucellosis as risk factors for the presence of anti-B. abortus antibodies. These results demonstrate no change in the prevalence when comparing initial studies conducted in 2002. Given our findings, it is recommended that policies for brucellosis control include a widespread vaccination program for higher prevalence areas and eradication approach to lower prevalence areas. All steps related to correct immunization of the herds should be verified and improved by training and education. Health education action must be carried out informing farmers about the risks of introducing animals not tested for brucellosis into their herds and the benefits of testing their herds regularly.

High Occurrence of Chelonid Alphaherpesvirus 5 (ChHV5) in Green Sea Turtles Chelonia mydas with and without Fibropapillomatosis in Feeding Areas of the São Paulo Coast, Brazil.

Chelonid alphaherpesvirus 5 (ChHV5) has been consistently associated with fibropapillomatosis (FP), a neoplastic disease that affects sea turtles globally. The DNA of ChHV5 has been detected in cutaneous and noncutaneous tissues (e.g., lung) of green sea turtles Chelonia mydas with (FP+) and without (FP-) clinical signs of FP, indicating a persistent ChHV5 infection. Previously published and custom primer pairs were used to amplify the fragments of ChHV5 unique long (UL) partial genes (UL30 and UL18) through end-point PCR from cutaneous tumors (n = 31), nontumored skin (n = 49), and lungs (n = 26) from FP+ (n = 31) and FP- (n = 18) green sea turtles. The DNA of ChHV5 was detected in cutaneous tumors (80.6%, 25/31), nontumored skin (74.2%, 23/31 FP+; 27.8%, 5/18 FP-), and lung samples (91.7%, 11/12 FP+; 100%, 14/14 FP-). The high occurrence of ChHV5 observed in lung samples from FP- individuals was unexpected (14/14), providing the first evidence of ChHV5 DNA presence in lungs of individuals without FP. Our results also revealed high ChHV5 occurrence among the tested cohort (93.9%, 46/49) and suggested that a large proportion (83.4%, 15/18) of FP- green sea turtles had subclinical ChHV5 infections. Hence, our findings support the hypothesis that ChHV5 requires one or more possibly environmental or immune-related co-factors to induce FP.

High discrimination of Mycobacterium bovis isolates in Brazilian herds by spoligotyping.

Bovine tuberculosis is an infectious disease caused by Mycobacterium bovis (M. bovis), that leads to economic losses in infected herds and it is also considered an important zoonosis. The molecular typing methods of M. bovis isolates are fundamental for the bovine tuberculosis surveillance system, and spoligotyping is the standard genotyping technique for this species. Thus, the aim of the present study is to analyze the spatial and cluster distribution of M. bovis strains from several regions of Brazil through molecular typing. Spoligotyping technique was applied on 422 isolates identified as M. bovis, and Ripley's K function was used to perform the spatial and cluster analysis of each identified profile. Forty-three (43) different profiles were identified and spoligotype SB0121 was the most frequent and showed a uniform pattern in the spatial distribution while spoligotypes SB0295, SB1380 and SB1050 formed clusters. In addition, three novel spoligotype profiles (SB2361, SB2362, SB2364) were identified in different herds. In this perspective, it is believed that molecular identification and typing can significantly improve the performance of surveillance systems for bovine tuberculosis in Brazil.

Analysis of the cattle trade network in the state ofMato Grosso, Brazil / Análise da rede de trânsito de bovinos no estado de Mato Grosso, Brasil

We characterized the network of cattle movements in Mato Grosso, Brazil­a state responsible for a significant amount of Brazilian beef exports. In this analysis, we were particularly interested in the importance of slaughterhouses in the network of cattle movements, in the characteristics of the trade for different purposes (especially for reproduction, fattening, and slaughter), and about the importance of the main traders. We found that the median distance of all movements was 79.0 km, with an interquartile range between 37.2 and 163.2 km, which suggests a relatively short-range trade pattern; roughly 20% of the premises purchasing more animals were responsible for 95% of the animals purchased and 20% of the premises selling more animals were responsible for 86% of the animals sold, indicating the importance of the cattle trade hubs. Fitting the degree distribution using a power-law distribution, we obtained a scaling parameter of 2.59, indicating that the cattle movement network of Mato Grosso is less dense than other observed cattle movement networks. The networks for fattening, reproduction, and slaughtering only comprised 73%, 56%, and 25% of all nodes and 52%, 30%, and 17% of all edges, respectively; and slaughterhouses had the highest in-degrees and total degrees, followed by markets and farms, playing the role of main cattle trade hubs. Therefore, slaughterhouses are potentially useful as surveillance points to detect cases, and controlling important trader premises may optimize the use of resources for controlling diseases.(AU)

Caracterizamos a rede de trânsito de bovinos em Mato Grosso, Brasil ­ um estado responsável por uma quantidade significativa das exportações brasileiras de carne bovina. Nesta análise, o interesse foi na importância de abatedouros na rede de trânsito de bovinos, nas características do comércio para diferentes finalidades (especialmente para reprodução, engorda e abate), e sobre a importância dos principais comerciantes. Encontramos que a distância mediana de todos os movimentos foi de 79,0 km, com um intervalo interquartil entre 37,2 e 163,2 km, o que sugere um padrão de comércio de alcance relativamente curto; cerca de 20% dos estabelecimentos que compram mais animais foram responsáveis por 95% dos animais comprados e 20% dos estabelecimentos que vendem mais animais foram responsáveis por 86% dos animais vendidos, o que mostra a importância dos principais comerciantes de bovinos. Ajustando a distribuição de graus usando uma distribuição de lei de potência, obtivemos um parâmetro de escala de 2,59, indicando que a rede de movimentação de bovinos de Mato Grosso é menos densa do que outras redes de trânsito bovino observadas. As redes para engorda, reprodução e abate compreenderam 73%, 56% e 25% de todos os nós e 52%, 30% e 17% de todas as arestas, respectivamente; e os frigoríficos tiveram os mais altos graus de entrada e totais, seguidos por mercados e fazendas, desempenhando o papel de principais pontos de comércio de gado. Por conseguinte, abatedouros são potencialmente úteis como pontos de vigilância para detectar casos, e o controle de estabelecimentos importantes para o comércio pode otimizar o uso de recursos para o controle de doenças.(AU)

Congenital Transmission of Toxoplasma gondii After Experimental Reinfection With Brazilian Typical Strains in Chronically Infected Sheep.

Toxoplasma gondii is a cause of congenital diseases, miscarriages and stillbirths in production animals. In Brazil, non-archetypal genotypes of the parasite may be related to severe disease. Experimental infection with T. gondii was studied in sheep to analyse congenital transmission-related parameters in reinfections with different Brazilian parasite strains. Thirteen T. gondii-seronegative sheep were orally infected with 2 × 103oocysts for the primary infection: G1 (4 animals) were inoculated with TgCatBr71 strain (Type BrI genotype) and G2 andG3 (5 and 4 animals, respectively) withTgCatBr60 strain (Type BrIII genotype). After chronification of infection, the animals were impregnated. A second infection was performed after 60 days of gestation. TheG1 andG3 animals were inoculated withTgCatBr60BrIII and the G2 animals withTgCatBr71 BrI oocysts. The effects of reinfection were compared with a control group (5 animals) through physical examination, ultrasound imaging and serology. Ovine experimental infections were evaluated using mouse bioassays, molecular analysis, serological tests, histopathology, and immunohistochemistry. No abortions occurred; a seropositive lamb and a mummified fetus from G2-BrIIIxBrI were produced. The vertical transmission rate detected in lambs from chronically infected sheep was 31.6% (6/19). It is demonstrated that reinfection and subsequent congenital transmission occured in one sheep with a primary Brl infection challenged with BrIII genotype of T. gondii. In a twin pregnancy from G2-BrIIIxBrI, congenital transmission from a latent infection was detected in both lambs. Congenital transmission could not be tracked in three lambs. Overall, previous T. gondii infection may fail to protect against congenital transmission from a reinfection and primary infection induced insufficient protection against vertical transmission which must be taken into account in decision-making for the use of seropositive animals as breeders. Similar trials with larger groups and contemplating host cellular immune response studies should be conducted to evaluate the actual impact of T. gondii reinfection involving different strains in sheep.

Validity of a two-stage cluster sampling design to estimate the total number of owned dogs.

Estimates of owned dog population size are necessary to calculate measures of disease frequency and to plan and evaluate population management programs. We calculated the error and bias of estimates of the total number of owned dogs using a two-stage cluster sampling design. The estimates were conditioned on sample composition as well as on size and heterogeneity of the spatial distribution of owned dog populations. For this, we simulated nine cities that differed systematically in size (number of census tracts) and heterogeneity (variance of the number of dogs per census tract). Then, we defined 16 scenarios to calculate the sample composition using an algorithm that incorporated data from a pilot sample, estimates of cost, and prior specifications of the expected error and confidence level. In three additional scenarios of predefined sample composition, the numbers of primary and secondary sampling units were: 30 × 30, 50 × 20 and 65 × 15. Finally, for each city and sample composition, we selected primary sampling units (census tracts) with probability proportional to its size and with replacement, and secondary sampling units (households) by simple random sampling. For each city and composition we selected 500 samples, totaling 85500 samples. The distribution of errors conditioned on the sample composition and city showed that estimates were accurate (average mean bias = 0.006%, maximum mean bias = 0.3%). All sample compositions resulted in errors between 4% and 7% in cities with low heterogeneity. In cities with high heterogeneity, the errors for the various compositions ranged as follows: 8-11% (calculated), 11-13% (65 × 15), 12-14% (50 × 20) and 15-17% (30 × 30). The sample size of predefined compositions was between 33% and 87% lower than the sample size of calculated compositions. Therefore, the predefined compositions have an operational advantage (reduced sampling effort) and simplify the sampling design (calculation of sample composition is not needed). Furthermore, the expected error of estimates under different scenarios is known for each predefined composition. In the absence of information about the heterogeneity of the cities, the 65 × 15 is the more conservative composition.

Seroprevalence of Leptospira spp infection and its risk factors among domestic dogs in Bogotá, Colombia.

Different analytical tools were used to determine the seroprevalence of and risk factors associated with Leptospira spp infection in 192 domestic dogs (Canis familiaris) in Bogotá, Colombia. Using the microscopic agglutination test (MAT), a battery of 16 Leptospira serovars were tested. The seroprevalence of Leptospira spp was calculated as 36.46% (95% CI 0.30-0.43). A questionnaire was applied to the dogs' owners at the time of sampling and the variables "Water sources near home" and "Dog hunting rodents" were identified as risk factors for leptospirosis occurrence in the urban area of Bogotá. Geographical coordinates relating to the dogs' households were obtained in order to map out the spatial distribution of reactive and unreactive dogs. Additionally, we found that the mean annual precipitation was higher at geographical locations with reactive animals than at those with unreactive dogs (p < 0.05). Preventing exposure of dogs to rodents and waste-water bodies that could be contaminated with Leptospira might effectively reduce occurrences of leptospirosis. Moreover, promoting preventive programs and vaccination of dogs against leptospirosis in areas of higher precipitation and prior to rainy months could be an effective strategy for leptospirosis prevention.

Livestock markets play an important role in the cattle movement network in Pernambuco, Brazil / Feiras de gado desempenham papel importante na rede de trânsito de bovinos em Pernambuco, Brasil

The animal trade is an important risk factor that affects the spread of diseases among animals and herds. The goal of the present study was to characterize the cattle movement network in Pernambuco, Brazil, based on the animal movement permits (Guias de Trânsito Animal; GTAs) from 2012 to 2013, and identify the intensity of the commercial relationship between farm premises. A total of 737,950 GTAs were issued, and the movement of 3,481,185 cattle (1,688,585 in 2012 and 1,792,600 in 2013) was analyzed. Of the moved animals analyzed, 52.57% (1,829,907/3,481,185) were involved in the movement of cattle in or out of livestock markets, indicating that livestock markets played a major role in the network. Approximately 20% of the more-connected premises were responsible for approximately 87% of the movement related to sales and 95% of the movement related to purchases. Considering the important role of livestock markets and the intense cattle trade between farm premises, surveillance, and control measures could be more efficient if targeted to livestock markets and highly connected premises to prevent the spread of infectious diseases.(AU)

O comércio de animais é um importante fator de risco para a disseminação de doenças entre animais e rebanhos. O objetivo do presente estudo foi caracterizar a rede de movimentação de bovinos em Pernambuco, com base nas guias de trânsito animal (GTAs) de 2012 a 2013, e identificar a intensidade da relação comercial entre os estabelecimentos. Foram analisadas 737.950 GTAs emitidas, e as movimentações de bovinos totalizaram 3.481.185 animais (1.688.585 em 2012 e 1.792.600 em 2013). Um percentual de 52,57% (1.829.907/3.481.185) das movimentações de bovinos envolveu entrada ou saída de feiras de gado, indicando que as feiras desempenharam um papel importante na rede. Aproximadamente 20% dos estabelecimentos mais conectados foram responsáveis por aproximadamente 87% das movimentações relacionadas às vendas, e 95% das movimentações, relacionadas às compras. Considerando o importante papel das feiras e o intenso comércio de bovinos entre as propriedades, medidas de vigilância e controle podem ser mais eficientes se aplicadas em feiras e estabelecimentos altamente conectados, para prevenir a propagação de doenças infecciosas.(AU)

Challenges in Evaluating the Severity of Fibropapillomatosis: A Proposal for Objective Index and Score System for Green Sea Turtles (Chelonia mydas) in Brazil.

Fibropapillomatosis (FP) is a neoplastic disease that affects marine turtles worldwide, especially green sea turtles (Chelonia mydas). FP tumors can develop on the body surface of marine turtles and also internally in the oral cavity and viscera. Depending on their quantity, size and anatomical distribution, these tumors can interfere with hydrodynamics and the ability to feed, hence scoring systems have been proposed in an attempt to quantify the clinical manifestation of FP. In order to establish a new scoring system adapted to geographic regions, we examined 214 juvenile green sea turtles with FP caught or rescued at Brazilian feeding areas, counted their 7466 tumors and classified them in relation to their size and anatomical distribution. The patterns in quantity, size and distribution of tumors revealed interesting aspects in the clinical manifestation of FP in specimens studied in Brazil, and that FP scoring systems developed for other areas might not perform adequately when applied to sea turtles on the Southwest Atlantic Ocean. We therefore propose a novel method to evaluate the clinical manifestation of FP: fibropapillomatosis index (FPI) that provides the Southwest Atlantic fibropapillomatosis score (FPSSWA). In combination, these indexing and scoring systems allow for a more objective, rapid and detailed evaluation of the severity of FP in green sea turtles. While primarily designed for the clinical manifestation of FP currently witnessed in our dataset, this index and the score system can be adapted for other areas and compare the characteristics of the disease across regions. In conclusion, scoring systems to classify the severity of FP can assist our understanding on the environmental factors that modulate its development and its impacts on the individual and population health of green sea turtles.

Large-scale study of herd-level risk factors for bovine brucellosis in Brazil.

Bovine brucellosis is an important zoonosis caused by Brucella abortus that negatively impacts livestock productivity. In 2001, Brazil launched a new national program aimed at eradicating animal brucellosis that included large-scale studies of the prevalence and risk factors to support strategic decision-making. These studies were implemented by the animal health authorities and were underpinned by the scientific coordination of the University of São Paulo and the University of Brasília. The state-level results were published and revealed important differences in herd prevalence among regions. The risk factors varied across states and did not clearly explain the observed spatial disease spread. This study used a consolidated herd-level database of 14 states and 17,100 herds, from the prevalence surveys' data, to gain insights into herd profiles and cattle production practices that might be associated with the risk of brucellosis. At the time of data collection, the study area comprised just over 56 million bovine females aged over 24 months and approximately 1.8 million herds. After an exploratory univariable analysis, all factors with p≤0.20 were included in a multiple logistic regression model, using the design-based method in order to take herd sampling weights into account. The number of females in the herd markedly increased the risk of infection; compared with smaller herds (less than 30 females), the odds ratio was 3.42 [CI 95% 2.98-3.91] for herds with 31 to 100 females, 5.68 [4.92-6.55] for herds with 101 to 400 females, and 13.14 [10.94-15.78] for herds with more than 400 females. The risk was higher for extensive cattle production farms (OR=1.23 [1.07-1.42]) and for farms that purchased replacement stock from cattle traders (OR=1.27 [1.08-1.47]) or directly from other farms (OR=1.19 [1.07-1.32]). The exclusive use of artificial insemination (OR=0.57 [0.4-0.81]) and regular veterinary support (OR=0.68 [0.6-0.77]) appeared to be protective factors. These findings are consistent with the regional prevalence trends observed in the study and provide key guidance for the planning of the national effort to control and eradicate brucellosis. High vaccination coverage of heifers is recommended, especially when targeted to areas where large-scale extensive cattle production predominates. The smaller, more intensive herds, are good candidates for disease accreditation schemes.

Infection of mice with oocysts of Toxoplasma gondii by oral route showed differences of virulence from Brazilian RFLP genotypes BrI and BrIII.

South American strains of Toxoplasma gondii present higher genetic diversity than classical European strains. We compared the virulence of two non-archetypal Brazilian genotypes of T. gondii to mice. Oocysts of four isolates, two genotype BrI (TgCatBr71 and TgShBr11) and two BrIII (TgCatBr74 and TgCatBr60) were obtained from cats fed experimentally infected mice. After sporulation, 5.0×10(1) and 1.0×10(2) oocysts were orally administrated to Swiss albine mice in Experiments #1 and #2, respectively (4-10 mice/group). Humoral response from dead and surviving mice was analyzed on days 9 to 35 post-infection. Microscopic observations of lungs and brains were performed for tachyzoites and cysts visualization in fresh preparations. Negative results were tested by PCR. Virulence after infection with oocysts is dose dependent for genotype BrIII isolates, but not for BrI. Differences in mortality were observed among isolates from genotype BrIII on Experiment #1. Intra-genotype phenotypic variation related to the parasite stage of infection was demonstrated and this characteristic should be further studied and may influence future work regarding the role of virulence amid hosts.

Monitoring techniques in the capture and adoption of dogs and cats.

The continuous improvement of the information systems of organizations that work toward the control of stray dog and cat populations facilitates the implementation of programs aimed at reducing the number of animals that roam free in public streets. This study aimed to present techniques to improve the understanding of the spatial distribution of stray dogs and cats and of people who adopt these animals and the fate of these animals in zoonosis control centers (ZCC). Ripley's K function was used with a Euclidean distance graph to detect the distribution pattern of dogs and cats captured and of the people who adopted these animals. An estimate of the kernel density was used to allow a better assessment of the spatial distribution of the phenomenon studied. The results showed that the distribution of captured animals and of the people who adopted these animals form a spatial cluster (p = 0.01). Most of the animals were captured near the premises of the ZCC and near the downtown area. Factors such as the abandonment of animals near animal control agencies and the availability of food sources are the main hypotheses associated to the distribution of the captures. The awareness of the people who live in places where there is a greater number of stray animals and the distribution of the urban population are the main hypotheses to explain the distribution of the adoptions. The results will help to implement control measures over these populations in the most problematic areas.

Dog and cat management through sterilization: Implications for population dynamics and veterinary public policies.

The present study aimed to compare different sterilization scenarios allowing the adoption of the most adequate strategy to control owned dog and cat population sizes as the official veterinary public policy for animal control in an urban area of Campinas municipality, Brazil. To achieve this goal, the vital parameters of the owned pet population were measured in a neighborhood of Campinas called Jardim Vila Olimpia through questionnaires used in two census studies performed in February 2012 and June 2013. Different hypothetical sterilization scenarios were compared with the scenario of a single sterilization campaign performed in the study area between the census studies. Using a deterministic mathematical model, population dynamics were simulated for these different scenarios. We have observed that for both owned dogs and cats, the impact on the population size achieved by a single sterilization campaign would be diluted over the years, equating to the impact achieved by the usual sterilization rate practiced before the sterilization campaign yearly. Moreover, using local and global sensitivity analyses, we assessed the relative influence on animal population evolution of each vital parameter used in the mathematical models. The more influential parameters for both species were the carrying capacity of the environment and sterilization rates of males and females (for both species). We observed that even with sterilizing 100% of the intact animals annually, it would not be possible to obtain proportions greater than 86% and 88% of sterilized dogs and cats, respectively, after 20 years due to the high introduction of new intact animals. There is no public dog and cat sterilization service in place in the city, and sporadic and local sterilization campaigns are performed with a prior communication to the owners to bring their animals to be sterilized in a selected veterinary facility. If a sterilization campaign was performed annually in the study area, it would have the most favorable cost effectiveness ratio after 20 years compared to the scenarios of 50% and 100% sterilization of intact animals annually. These results allowed the veterinary public policy stakeholders to make decisions based on scientific evidence to implement adequate control of dog and cat populations in urban areas, aiming to reduce zoonosis transmission to humans and other problems associated with uncontrolled animal populations.

Infectious disease surveillance in animal movement networks: An approach based on the friendship paradox.

The network of animal movements among livestock premises is an important topological structure for the spread of infectious diseases. The central focus of this study was to analyze strategies for selecting premises based on the friendship paradox ("your friends have more friends than you do") - in which premises that neighbor randomly selected premises are sampled for surveillance or control - to determine whether these strategies are viable alternatives for the surveillance and control of diseases in scenarios with insufficient data on animal movement. To test the effectiveness of these strategies, we performed three sets of simulations. In the first set, we examined the risk of spreading an infectious disease using the cattle movement network of the state of Mato Grosso, Brazil. All tested strategies based on the friendship paradox have comparable performance to the hub control strategy (controlling premises that sold more animals) and superior performance to random sampling in terms of both reducing the risk of purchasing infected animals and the number of premises that need to be controlled. In the second and third sets of simulations, we observed that the friendship paradox strategies were more sensitive than the random sampling strategy to detect cases and disease, respectively. The survey of the entire animal movement network to identify animal premises with a key role in trade is not always possible, either because the data are insufficient or because informal trade is significant. If surveying the network is not possible, all approaches based on knowledge of the network become useless. As an alternative, knowing that there is a hidden movement network that follows rules inherent to all networks, such as the friendship paradox, can be used to our advantage. Strategies based on the friendship paradox do not assume knowledge of the animal movement network and therefore may be viable alternatives for the surveillance or control of infectious diseases in the absence of network information, thus optimizing the use of human and financial resources.

Occurrence of antibodies anti-Toxoplasma gondii and anti-Neospora caninum in dogs from Natal, RN, Brazil / Ocorrência de anticorpos contra Toxoplasma gondii e Neospora caninum em cães de Natal, RN, Brasil

The occurrence of anti-Toxoplasma gondii and Neospora caninum in dogs from the municipality of Natal, RN, Brazil, was determined. Information about the presence of these coccidia in this species was not known. Blood samples were collected from 29 domiciled dogs which inhabit areas that surround two important protected areas of Atlantic Forest (Parque da Cidade and Parque das Dunas) and another 73 dogs that were sacrificed due to Leishmania spp. infection, in Center for Control of Zoonosis (CCZ) for the municipality of Natal. It was only possible to obtain information about the gender of dogs that live in the parks area. The presence of antibodies against each parasite was determined by indirect Fluorescence Antibody Test (IFAT), with a cutoff of 16 for T. gondii and 50 for N. caninum. Of the 102 dogs examined, 13 (12.7%, 95% CI 7.0-20.8%) were T. gondii positive and three (2.9%, CI 0.6-8.4%) for N. caninum. Association between: localities of obtaining samples (parks x CCZ) and sex of animals, with the occurrence of antibodies against each of the parasites, was determined by the Fisher exact test. For T. gondii association was found with males (p = 0.027) and dogs living close to parks (p = 0.008) had higher rates of infection. Associations were not observed in relation to N. caninum.

A ocorrência de anticorpos anti-Toxoplasma gondii e anti-Neospora caninum foi determinada em cães do município de Natal, RN, onde informações sobre a presença destes coccídios nessa espécie não era conhecida. Para tanto, foram utilizados 29 cães domiciliados, que habitam áreas que circundam duas importantes Unidades de Conservação de Mata Atlântica presentes no município (Parque da Cidade e Parque das Dunas), e outros 73 cães que foram sacrificados no Centro de Controle de Zoonoses de Natal por serem positivos a Leishmania spp. Somente em relação aos cães que vivem próximos aos parques foi possível a obtenção de informações sobre o sexo dos animais. A presença de anticorpos contra cada um dos coccídios foi determinada com a Reação de Imunofluorescência Indireta com ponto de corte de 16 para T. gondii e 50 para N. caninum. Dos 102 cães examinados, 13 (12,7%, IC 95% 7,0-20,8) foram positivos para T. gondii e 3 (2,9%, IC 0,6-8,4%) para N. caninum. Associação entre: localidades de obtenção das amostras (parques x CCZ) e sexo dos animais com a ocorrência de anticorpos contra cada um dos parasitos, determinada através do teste exato de Fisher, foram positivas para T. gondii, com os machos (p = 0,027) e cães que habitam próximos aos parques (p = 0,008) apresentando maiores taxas de infecção. Associações não foram observadas em relação a N. caninum.