Antimicrobial and disinfectant resistance of Salmonella Heidelberg from Brazilian flocks did not increase for ten years (2006-2016) / A resistência a desinfetantes e a antimicrobianos não aumentou em um período de 10 anos (2006 a 2016) em Salmonella Heidelberg isoladas de granjas avícolas brasileiras

Salmonella is a major cause of foodborne illness worldwide, and poultry and its derived products are the most common food products associated with salmonellosis outbreaks. Some countries, including Brazil, have experienced an increased prevalence of Salmonella Heidelberg among their poultry flocks. Some isolates have also presented high resistance to antimicrobial agents and persist in the poultry farm environment. This study aimed to compare the susceptibility of S. Heidelberg strains isolated in 2006 with those isolated in 2016 against disinfectants and antimicrobial agents. The results showed that all the strains were highly susceptible to sodium hypochlorite, regardless of the conditions and year of isolation. Resistance to benzalkonium chloride varied according to the conditions applied, but not to the year of isolation. Increased antimicrobial resistance from 2006-2016 was observed only for tetracycline. The results suggest that the antimicrobial and disinfectant resistance of S. Heidelberg did not increase for ten years (2006-2016). However, further analysis should include a larger number of S. Heidelberg isolates from poultry origin and additional antimicrobial agents for more precise conclusions about the increasing in antimicrobial resistance in the last years.(AU)

Salmonella é uma das principais causas das doenças transmitidas por alimento em todo o mundo, e a carne de frango e produtos derivados são os principais alimentos associados com surtos de salmonelose em humanos. Alguns países, incluindo o Brasil, têm observado um aumento da ocorrência de Salmonella Heidelberg nas suas granjas avícolas. Além disto, alguns isolados têm apresentado alta resistência aos antimicrobianos e têm persistido no ambiente de produção avícola. Neste contexto, o objetivo deste estudo foi comparar a susceptibilidade de cepas de S. Heidelberg isoladas em 2006 com aquelas isoladas em 2016 contra desinfetantes e agentes antimicrobianos. Os resultados demonstraram que as cepas foram altamente resistentes a hipoclorito de sódio, independentemente das condições e do ano de isolamento. A resistência ao cloreto de benzalcônio variou de acordo com as condições testadas, mas não com o ano de isolamento. Um aumento da resistência aos antimicrobianos de 2006 a 2016 foi observado apenas para tetraciclina. Os resultados sugerem que a resistência aos desinfetantes e aos antimicrobianos não aumentou em um período de dez anos (2006-2016). Entretanto, novas análises devem incluir um número maior de cepas de S. Heidelberg isoladas de fontes avícolas e outros agentes antimicrobianos para uma conclusão mais precisa sobre o aumento da resistência antimicrobiana nos últimos anos.(AU)

Antimicrobial and disinfectant resistance of Salmonella Heidelberg from Brazilian flocks did not increase for ten years (2006-2016)

ABSTRACT: Salmonella is a major cause of foodborne illness worldwide, and poultry and its derived products are the most common food products associated with salmonellosis outbreaks. Some countries, including Brazil, have experienced an increased prevalence of Salmonella Heidelberg among their poultry flocks. Some isolates have also presented high resistance to antimicrobial agents and persist in the poultry farm environment. This study aimed to compare the susceptibility of S. Heidelberg strains isolated in 2006 with those isolated in 2016 against disinfectants and antimicrobial agents. The results showed that all the strains were highly susceptible to sodium hypochlorite, regardless of the conditions and year of isolation. Resistance to benzalkonium chloride varied according to the conditions applied, but not to the year of isolation. Increased antimicrobial resistance from 2006-2016 was observed only for tetracycline. The results suggest that the antimicrobial and disinfectant resistance of S. Heidelberg did not increase for ten years (2006-2016). However, further analysis should include a larger number of S. Heidelberg isolates from poultry origin and additional antimicrobial agents for more precise conclusions about the increasing in antimicrobial resistance in the last years.

RESUMO: Salmonella é uma das principais causas das doenças transmitidas por alimento em todo o mundo, e a carne de frango e produtos derivados são os principais alimentos associados com surtos de salmonelose em humanos. Alguns países, incluindo o Brasil, têm observado um aumento da ocorrência de Salmonella Heidelberg nas suas granjas avícolas. Além disto, alguns isolados têm apresentado alta resistência aos antimicrobianos e têm persistido no ambiente de produção avícola. Neste contexto, o objetivo deste estudo foi comparar a susceptibilidade de cepas de S. Heidelberg isoladas em 2006 com aquelas isoladas em 2016 contra desinfetantes e agentes antimicrobianos. Os resultados demonstraram que as cepas foram altamente resistentes a hipoclorito de sódio, independentemente das condições e do ano de isolamento. A resistência ao cloreto de benzalcônio variou de acordo com as condições testadas, mas não com o ano de isolamento. Um aumento da resistência aos antimicrobianos de 2006 a 2016 foi observado apenas para tetraciclina. Os resultados sugerem que a resistência aos desinfetantes e aos antimicrobianos não aumentou em um período de dez anos (2006-2016). Entretanto, novas análises devem incluir um número maior de cepas de S. Heidelberg isoladas de fontes avícolas e outros agentes antimicrobianos para uma conclusão mais precisa sobre o aumento da resistência antimicrobiana nos últimos anos.

Characterization of embryonic mortality in broilers / Caracterización de mortalidad embrionaria en pollos de engorde

ABSTRACT Objective. The purpose of this study was to characterize the incidence of EM in Ross 308 strain eggs. Materials and methods. A prospective cohort study was performed, through candling and embryodiagnosis, in 4 groups of eggs coming from 4 different age breeders. Other data such as percentage of infertility, malformation, malposition, cracked and contaminated eggs were reported. Results. General EM reached 16.08% IC95% (14.69; 17.60) and was different among the different age-groups (p<0.001), being higher for eggs from 64 week-old breeders with 27.66% IC95%(23.92; 31.99) and lower for the 47 weeks old ones (8.84% IC95%) (6.97; 11.22). In the first week of incubation 57.53% of the embryos died and mortality was at its highiest during days 1 and 3; in the second week EM was 38.42% died, with a maximum of deaths between days 19 and 21. Conclusions. This study allowed confirmation on the biphasic behaviour of EM, although there are variations in the peaks of mortality possibly attributed to differences in production conditions for each enterprise.

RESUMEN Objetivo. El propósito de este estudio fue caracterizar la incidencia de mortalidad embrionaria (ME) en huevos de estirpes Ross 308 en una empresa de Santander, Colombia. Materiales y métodos. Se realizó un estudio de cohorte prospectivo en el cual se siguieron durante la incubación, por medio de ovoscopía y embriodiagnóstico, 4 grupos de huevos provenientes de reproductoras de 4 edades diferentes. Se reporta el porcentaje de infertilidad, de malformaciones, malposición, huevos fisurados y contaminados. Resultados. La ME general alcanzó 16.08% IC95%(14.69; 17.60) y fue diferente entre los grupos de edad (p<0.001); esta fue mayor para los huevos de reproductoras de 64 semanas con 27.66% IC95% (23.92; 31.99) y menor para las de 47 semanas con 8.84% IC95% (6.97; 11.22). En la primera semana de incubación murió el 57.53% de los embriones y se presentó el pico de muerte entre los días 1 y 3; la segunda semana murió el 38.42%, con un máximo de muertes entre el día 19 y 21. Conclusiones. Este estudio, es el primero de su naturaleza para la zona y la estirpe y permitió confirmar el comportamiento bifásico de la ME aunque existen variaciones en los picos de mortalidad atribuidas posiblemente a las diferencias de las condiciones de producción propias de las empresas.

Epidemiology of Mycoplasma agalactiae and Mycoplasma mycoides cluster in flocks of northeastern Brazil / Epidemiologia de Mycoplasma agalactiae e Mycoplasma mycoides cluster em rebanhos do nordeste do Brasil

ABSTRACT: The present study aimed to investigate contagious agalactia (CA) in flocks from Pernambuco State. The study involved 225 goats and 63 ewes; 288 milk samples and 100 vaginal swabs were collected in total. The PCR assays were carried out using specific primers to Mycoplasma agalactiae and the Mycoplasma mycoides cluster. Among the goat's milk samples,12.0% (27/225) were positive for Mycoplasma agalactiae DNA, while 5.3% (12/225) contained the Mycoplasma mycoides cluster. Of the vaginal swabs taken from goats, 15.4% (12/78) were positive for Mycoplasma agalactiae DNA and 3.8% (3/78) contained the Mycoplasma mycoides cluster. In the case of ewes, 4.3% (1/23) of the milk samples contained Mycoplasma agalactiae DNA, and 7.5% (3/40) were positive for the Mycoplasma mycoides cluster. Vaginal swabs taken from sheep´s were negative. Analysis of risk factors for mycoplasmosis, showed that goats and sheep flocks on the extensive breeding system are more likely to have mycoplasmosis than those on the intensive breeding system (odds ratio (OR) 6.2; p=0.004); meat goat and sheep flocks are more likely to have infection compared to dairy flocks (OR 4.8; p=0.011); unclean animal housing increases the chances of infection (OR 5.0; p=0.031) and not performing quarantine increases the chances of mycoplasmosis (OR 4.6; p=0.042). Based on these findings we conclude that CA syndrome in the semiarid region of Pernambuco state can be associated with Mycoplasma agalactiae and Mycoplasma mycoides cluster.

RESUMO: O objetivo deste estudo foi investigar a Agalaxia contagiosa em rebanhos do estado de Pernambuco. Foram examinadas 225 cabras e 63 ovelhas, das quais foram colhidas 288 amostras de leite e 100 suabes vaginais. Foram realizadas reações da PCR com iniciadores específicos para Mycoplasma agalactiae e Mycoplasma mycoides cluster. A frequência total de Mycoplasma agalactiae em amostras de leite caprino foi de 12,0% (27/225) e de 5,3% (12/225) para Mycoplasma mycoides cluster. Dos suabes vaginais de cabras as frequências detectadas na PCR foram de 15,4% (12/78) para Mycoplasma agalactiaee 3,8% (3/78) para Mycoplasma mycoides cluster. Em leite de ovelhas a frequência de Ma foi de 4.3% (1/23) e de 7,5% (3/40) para Mycoplasma mycoides cluster. Na análise dos fatores de risco para micoplasmoses verificou-se que rebanhos de caprinos e ovinos mantidos no sistema extensivo são mais prováveis de adquirir micoplasmose quando comparados com o sistema intensivo (odds ratio (OR) 6,2; p=0,004); rebanhos de caprinos e ovinos de corte são mais prováveis de adquirir micoplamsose do que rebanhos de leite (OR 4,8; p=0,011); não realizar limpeza das instalações aumenta as chances de infecção (OR 5,0; p=0,031); não realizar quarentena aumenta as chances das micoplasmoses estudadas (OR 4,6; p=0,042). Conclui-se que M. agalactiae e Mycoplasma mycoides cluster estão envolvidos na síndrome de CA em rebanhos de caprinos e ovinos do semiárido pernambucano.

Investigation of avian diseases eradication in parent breeding flocks in China in 2015 / 中国兽医学报

In order to understand the management measures,technique abilities and difficulties in controlling and eradicating avian diseases in parent breeding flocks,the current situation of avian disease eradication in breeding flocks was investigated by China Animal Disease Control Centre in 19 provinces in July 2015.Questionnaires investigation was conducted and the feedbacks were received from 214 parent breeding flocks.This study summarized and analyzed the information of farm management,breeding resources,avian disease surveillance and disease eradication in these flocks,which will provide the basic data to promote the avian diseases control and eradication in China.

Comportamiento predestete de cabritos cruzados en Guanajuato, México / Pre-weaning performance of crossbred goat kids from Guanajuato, Mexico

Objetivo. Los pesos al nacimiento y al destete fueron registrados para evaluar el comportamiento pre-destete de cabritos cruzado en ocho pequeñas fincas de producción de leche de cabra en Guanajuato, México. Materiales y métodos. Se usaron 234 registros de cabritos, las cabras fueron mantenidas en condiciones de pastoreo con suplementación de un concentrado comercial. Los cabritos eran cruzados, de las razas Sannen, Alpina y Toggenburg, los datos fueron analizados con un modelo estadístico que considero los efectos de rebaño (RE), grupo contemporáneo (GC), número de parto (NP), tipo parto (TP) y sexo del cabrito (SC). Resultados. Las medias de peso al nacer, peso a los 60 días de edad y la ganancia diaria de peso fueron 3.4±0.5 (rango 2.0 a 5.5), 13.7±1.8 (rango 8.0 a 17.5) y 0.17±0.02 (0.08 a 0.23 kg). El peso al nacimiento fue afectado (p<0.01) por RE, GC, NP, TP y SC. Sin embargo, el peso a 60 días y ganancia diaria de peso fueron afectadas (p<0.05) por RE y SC. Conclusiones. El rebaño afectó el comportamiento de los cabritos.

Objective. Birth and weaning weights were recorded, to valuate pre-weaning performance of crossbred kids, in eighth small milk goat flocks, from Guanajuato, Mexico. Materials and methods. Records of 234 kid dings were used; the goats were kept under grazing rangeland with supplementation of commercial concentrate. The kids were crossbred between Sannen, Alpine and Toggenburg breeds. Data was analyzed by a statistical model in which the flock effects (FL), contemporary group (CG), parity number (PN), litter size (LS) and sex of the kid (SK) were considered. Results. Birth weights averaged 3.4±0.5 kg (range 2 to 5.5 kg) and weight at 60 days of age averaged 13.7±1.8 kg (range 8.0 to 17.5 kg); and daily weight gain averaged 0.17±0.02 kg (range 0.08 to 0.23 kg). Birth weights were affected (p<0.01) by FL, CG, PN, LS and SK. However, weight at 60 days and daily weight gain were affected (p<0.05) by FL and SK. Conclusions. The flock affected the performance of the kids.

seroprevalencia de la leucosis enzoótica bovina y su asociación con signos clínicos y factores de riesgo en rebaños lecheros del estado barinas, venezuela / Seroprevalence of Enzootic Bovine Leukosis and its Association with Clinical Signs and Risk Factors in Dairy Herds from Barinas State, Venezuela

Se realizó un estudio sobre la seroprevalencia de la leucosis enzoótica bovina (LEB) en 360 bovinos lecheros, representativos de los municipios Pedraza y Barinas del estado Barinas, Venezuela, durante el periodo comprendido entre julio y noviembre 2007. En todos ellos se evaluó la presencia de signos clínicos compatibles con LEB (caquexia, decaimiento, y tumefacciones en los ganglios linfáticos supraescapulares e inguinales superficiales). Se recolectaron muestras de sangre, para la detección de anticuerpos y la proporción de linfocitos, lo cual se hizo mediante la prueba de ELISA y por contaje de linfocitos, respectivamente, relacionándose el porcentaje de animales seropositivos con el hallazgo de signos, tumefacciones en los ganglios y valores linfocíticos. Adicionalmente, se evaluó la seropositividad entre sexos, grupos etarios y número de partos, como factores de riesgo, mediante la prueba de Chi cuadrado (X²). Se detectaron 219 de 360 (60,83%) bovinos con anticuerpos específicos contra el virus de la LEB (VLEB), indicando una prevalencia elevada de distribución uniforme, en ambos municipios. La proporción de animales seropositivos con signos clínicos resultó ligeramente superior (33,79%) a la de los seronegativos (19,86%), aunque estos valores no fueron estadísticamente significativos. De igual manera, no se encontraron diferencias entre los seropositivos y seronegativos, en cuanto a las tumefacciones detectadas en los ganglios detectados, indicando que la ausencia de ellas no implica ausencia de infección. Las elevadas proporciones de linfocitos en los bovinos seropositivos y seronegativos resultaron similares, revelando no estar relacionadas con la infección por el VLEB. Con respecto a los factores de riesgo, la edad y el número de partos, mostraron estar asociados con la presencia de anticuerpos (P=0,0030 y P=0,0001, respectivamente), mientras que para el sexo no se detectaron. Estos resultados representan una contribución al conocimiento del comportamiento de la LEB en Venezuela.

An investigation was conducted to study the seroprevalence of enzootic bovine leukosis (EBL) in dairy cattle from the municipalities of Pedroza and Barinas, located at the State of Barinas, Venezuela, from July to November 2007. A total of 360 dairy cows were used. In all animals, the presence of clinical signs compatible with EBL, such as emaciation, weakness, tumefaction in suprascapular and superficial inguinal lymph nodes, were assessed. Blood samples positive to antibodies against EBLV were collected, specific antibodies to EBLV and lymphocyte proportion in samples were determined through the ELISA test and lymphocyte count, respectively. The percentage of positive animals was related to clinical findings, tumors, and lymphocytes values. Additionally, seropositivity among sex, age groups, and calving number, considered as risk factors, were also analyzed using the Chi square (X²) test. Of a total of 360 animals, 219 (60.83%) were positive to EBLV antibodies, indicating an elevated prevalence of uniform distribution in both municipalities. The proportion of seropositive animals with clinical signs was slightly higher (33.79%), when compared to seronegative animals (19.86%), although these values were not statistically significant. Likewise, no differences were found between serpositives and seronegatives regarding tumefaction detected, indicating that absence of such tumefaction does not imply lack of infection. The elevated amount of lymphocytes in both seropositive and seronegative animals was similar, reflecting no relationship with the infection through the EBLV. Concerning risk factors, age and calving number showed to be associated with the presence of antibodies (P=0.0030 and P=0.0001, respectively). In contrast, such association was not found for the variable sex. These results represent a contribution to the comprehension of EBL behaviour in Venezuela.

Bird mixed-flocks and nuclear species in a tecoma savanna in the Pantanal / Bandos mistos de aves e espécie nuclear em uma savana de ipês no Pantanal

In bird mixed flocks, a prominent species, the so-called nuclear species, improves the cohesion and maintenance of the flocks, while other less conspicuous species are assumed as satellite. In this study we described the composition, as well as examined the existence of both nuclear and satellite species in mixed flocks of a savanna in the Pantanal. The observations were developed using three transects during the dry season of 2002. Bird species abundance and respective rate of participation in mixed flocks were surveyed by transects, while intraspecific sociality, communication, foraging maneuvers of species, and responses to predators were sampled by direct observations. These parameters were evaluated to distinguish nuclear from satellite species. We observed 41 bird mixed flocks, which included from 2 to 17 species of which Suiriri suiriri (Vieillot), one of the most abundant species, was present in most flocks, often represented by 2-4 individuals, whereas most other species occurred lone or in pairs. While foraging by acrobatic maneuvers S. suiriri often gave contact calls, as well as earlier giving alarm calls if faced with a risk of predation. In addition, S. suiriri always started mixed flocks movements. Conversely, most other species were silent and closely inspected the vegetation while foraging. Such species always followed S. suiriri and seldom gave contact calls. Hence, the conspicuous traits exhibited by S. suiriri, potentially, are exploited by the other bird species as cues, which are important references for bird mixed flock cohesion in a savanna in the southern Pantanal.

Em bandos mistos de aves, a espécie nuclear possui características que promovem a coesão e manutenção dos bandos, enquanto espécies menos conspícuas são consideradas satélites. Este estudo teve como objetivos descrever a composição, bem como analisar a existência de espécies nucleares e satélites em bandos mistos em um tipo de savana do Pantanal Sul. As observações foram desenvolvidas ao longo de três trajetos durante a estação seca de 2002. A abundância das espécies e respectiva taxa de participação nos bandos mistos foram amostradas através de trajetos, enquanto dados sobre socialidade intra-específica, comunicação, manobras de forrageio e reação a predadores foram obtidos através de observações diretas. Esses parâmetros foram adotados como critérios, para distinguir espécies nucleares de satélites. Foram detectados 41 bandos mistos que incluíram de 2 a 17 espécies, sendo que Suiriri suiriri, uma das espécies mais abundantes na savana de ipês, esteve presente em praticamente todos os bandos, na forma de um par ou grupo de indivíduos que, regularmente, emitiam chamados de contato, enquanto forrageavam executando manobras acrobáticas. Também, emitiram chamados de alarme quando em risco de predação e foram seguidos pelas demais espécies durante os deslocamentos dos bandos. A maioria das outras espécies inspecionava a vegetação silenciosamente enquanto forrageavam, seguiam S. suiriri em seus deslocamentos e raramente emitiam chamados de contato. Portanto, características conspícuas exibidas por S. suiriri, potencialmente, são exploradas pelas demais espécies como importantes referências para coesão dos bandos mistos de aves em uma savana no Pantanal sul.