ABSTRACT This study aimed to analyze 19 isolates of Salmonella spp., from broiler litter swabs in the State of São Paulo, by typing and analyzing the detection of resistance genes associated with ESBL’s (Extended Spectrum Beta Lactamase), AMPC (C-type cephalosporinases) and carbapenemases by molecular and phenotypic techniques. A PCR microarray platform (Check and Trace by Check-Points) was used to identify the isolated serotype. The isolates were also evaluated for identification of carbapenemase genes, MCR 1-2 (colistin resistance), AmpC (C-type cephalosporins), and ESBLs (β-lactamases resistance). To identify phenotypic antibiotic resistance, the minimal inhibitory concentration (MIC) was evaluated with the antibiotics meropenem, amoxicillin, and ceftriaxone. The most prevalent serotypes identified were S. Infantis and S. Saintpaul, with a prevalence of 15.07% (3/19). Other strains identified were S. Cerro, S. Sandiego, S. Kentucky, S. Alachua, S. Javiana, S. Livingstone, S. Typhimurium, S. Heidelberg, non-enteric Salmonella, and a Salmonella not typifiable by the typing kit. All samples were negative for identifying carba resistance genes, MCR, ESBL, and AmpC. In the phenotypic profile, meropenem was the least resistant, while amoxicillin and ceftriaxone showed a high resistance pattern. The results show that phenotypic resistance is not associated with the presence of resistance genes studied here. In addition, the resistant bacteria found in MIC have resistance mechanisms not associated with the genes studied here. Additional measures must be implemented to prevent the indiscriminate use of antimicrobial agents therapeutically or as growth promoters.

ABSTRACT This study aimed to evaluate the efficacy of biofilms formed by lactic acid bacteria and Bacillus sp. (BLA) in preventing and controlling the formation of wild biofilms and/or planktonic forms of Salmonella Gallinarum (SG), Salmonella Heidelberg (SH), and methicillin-resistant Staphylococcus aureus (MRSA) on different surfaces. The SH and SG viability was evaluated in polystyrene plates, wood shavings, and soil samples. Two protocols were developed to examine the use of BLA in a preventive and control application. For analysis of Campylobacter jejuni (CJ) BLA was used only preventively in a polystyrene plate. Results showed that BLA was effective in preventing the growth of SG and SH in all matrices. The effectiveness of BLA for MRSA was lower than for SG and SH. The efficiency of BLA in preventing CJ growth seems to be related to the initial CJ contamination. BLA proves to be a potential alternative to control food-borne pathogens commonly encountered in animal production and food industry.

SUMMARY Raising backyard birds is a common practice in Brazil, mainly in the countryside or suburban areas. However, the level of respiratory pathogens in these animals is unknown. We sampled two hundred chickens from 19 backyard flocks near commercial poultry farms and performed ELISA to Infectious Bronchitis Virus, avian Metapneumovirus, Mycoplasma synoviae and Mycoplasma gallisepticum. We evaluated the association between the predictive ability of ELISA and Hemagglutination-inhibition (HI)by comparing results from eight flocks positive to Mycoplasma gallisepticum on ELISA. Besides, we assessed essential biosecurity measures in the properties (multiple species birds, rodent control, hygienic conditions, and water quality for the bird`s consumption). We could access the vaccination program only on four properties; in three of them, the birds were supposedly vaccinated for IBV. Overall the properties had a poor score for the biosecurity measures, and the seroprevalence in backyard poultry flocks for IBV, a MPV, MS, and MG were respectively 87.5% (14/16), 89.5% (17/19), 100 (19/19) and MG 84.21% (16/19). We found low specificity and predictive value between ELISA and HI in MG analysis and a positive correlation between the presence of clinical symptoms and mean MG titers. Backyard chicken are pathogens’ reservoirs and pose a risk for the commercial poultry farms in the region, and further efforts of the governmental entities and private sector of poultry production should consider these information to avoid future economic losses.

RESUMO: Objetivou-se incorporar informações genômicas de marcadores SNP (“single nucleotide polymorphism”) na avaliação genética das características “stay-green” (SG), arquitetura de planta (AP), aspecto de grãos (AG) e produtividade de grãos (PG) em feijoeiro-comum via modelos Bayesianos. Estes modelos foram comparados quanto a acurácia de predição e habilidade de estimação da herdabilidade para cada característica. Utilizaram-se informações de 80 cultivares genotipadas para 377 marcadores SNP, cujos efeitos de substituição alélica foram estimados por meio de cinco diferentes modelos Bayesianos: Bayes A (BA), B (BB), C (BC), LASSO (BL) e regressão “ridge” (BRR). Embora as acurácias de predição calculadas por meio de análise de validação cruzada tenham sido similares dentro de cada característica, o modelo BB se destacou para a característica SG, enquanto o modelo BRR foi indicado para as demais. As herdabilidades estimadas para SG, AP, AG e PG foram, respectivamente, 0,61, 0,28, 0,32 e 0,29. Em resumo, os métodos contemplados mostraram-se efetivos e de fácil implementação. O conjunto de marcadores utilizado pode auxiliar na seleção precoce de genótipos promissores, uma vez que a incorporação de informações genômicas aumenta a acurácia de predição do mérito genético estimado.

ABSTRACT: We aimed to apply genomic information based on SNP (single nucleotide polymorphism) markers for the genetic evaluation of the traits “stay-green” (SG), plant architecture (PA), grain aspect (GA) and grain yield (GY) in common bean through Bayesian models. These models were compared in terms of prediction accuracy and ability for heritability estimation for each one of the mentioned traits. A total of 80 cultivars were genotyped for 377 SNP markers, whose effects were estimated by five different Bayesian models: Bayes A (BA), B (BB), C (BC), LASSO (BL) e Ridge regression (BRR). Although, prediction accuracies calculated by means of cross-validation have been similar within each trait, the BB model stood out for the trait SG, whereas the BRR was indicated for the remaining traits. The heritability estimates for the traits SG, PA, GA and GY were 0.61, 0.28, 0.32 and 0.29, respectively. In summary, the Bayesian methods applied here were effective and ease to be implemented. The used SNP markers can help in the early selection of promising genotypes, since incorporating genomic information increase the prediction accuracy of the estimated genetic merit.

ABSTRACT The excellence of modern broiler production is based on the genetic improvement of broiler strains for high growth rate and high egg production, associated with technological developments in nutrition, management, and health. Over the last decades, the clinical biochemistry of broilers has been studied to determine serum biochemical component values; however, there are still many knowledge gaps on factors that determine changes in these values. In this study, the serum lipid and protein profiles of 4-week-old male and female Cobb broiler breeders were evaluated. Blood samples were collected on a commercial farm located in the city of Uberlândia, MG, Brazil. The following parameters were evaluated: total protein, albumin, globulin, albumin to globulin ratio (A/V), uric acid, urea, cholesterol, and triglyceride levels using an automatic analyzer. The results showed sex-specific biochemical patterns for most blood parameters evaluated. Moreover, the obtained values were different from those obtained in many published studies with broilers and commercial layers, stressing the need to develop further studies with chickens of different ages.

Abstract Campylobacteriosis is a worldwide foodborne zoonosis disease caused by Campylobacter jejuni. This microorganism is considered a commensal bacterium in chicken hosts. C. jejuni produces epithelial cell modifications and induces a cytokine gene transcription innate immunity repertoire. In the present study, we describe the invasiveness, morphological cellular modifications, and transcript level expressions of innate immune cytokines from C. jejuni-inoculated chicken ileum explants. C. jejuni was internalized by epithelial ileum cells at 15 minutes postinoculation (p.i.) and was detected intracellularly for 4hs (p.i.). Inoculated explants displayed significant increases in cell height. C. jejuni induced a significant elevation of Transforming Growth Factor Beta 3 (TGF-b3) and Interleukin-1b (IL-1b) transcripts. In conclusion, C. jejuni is internalized in explanted epithelial ileum cells, produces morphological cell modifications, and induces gene transcription of both anti-inflammatory and pro-inflammatory cytokines.

Storing hatchable eggs is a common practice in commercial hatcheries. However, storage time may negative effects on several performance parameters. An experiment was carried out to evaluate inverting egg position during storage of eggs laid by young and old layer breeders. Fertile eggs of 32 and 58-week-old breeders were stored for seven, 14, and 21 days at 18ºC ± 2ºC and 80% ± 10% relative humidity (RU). The following parameters were evaluated: egg weight loss, hatchability and hatchling weight, and embryodiagnosis results. Eggs stored with the small end up lost less weight during storage compared with the control eggs. Storing eggs for 14 days with the small end up reduced early embryo mortality, improving hatchability. In addition, hatchling weight increased. These results show that the detrimental effects of long storage periods may be alleviated when eggs are stored with the small end up to 14 days of storage.

Campylobacter sp is an important agent that causes foodborne infection, particularly in food of poultry origin. Therefore, the efficient control of the transmission routes in chicken farms is of outmost importance to prevent it from spreading. In chicken farms, the main transmission route of this microorganism is horizontal, as the vertical route continues to be the object of inconclusive researches. The objective of this study was to verify the presence of Campylobacter sp in breeder hens, meconium, and other organs of day-old chicks derived from these breeders in order to obtain information on vertical transmission. Microbiological analyses were performed, using cloacal swabs from 279 breeder hens. Positive breeders were segregated, and the presence of Campylobacter sp. was verified in their progeny by analyzing 117 meconium samples; 36 heart, liver and spleen samples (pool of 3 day-old chicks per sample), and 34 intestine samples (pool of 3 chickens in each sample). The analysis of the 279 breeder hens showed that 39 (13.97%) were positive for Campylobacter sp, using the cloacal swab method. The meconium and the organs of day-old chicks were not positive. The physiological characteristics of breeder hens, of eggs, and of Campylobacter sp favor the entrance of bacteria and their survival inside the eggs, and therefore, this probably is the contamination route of day-old chicks. However, chick meconium and organs were negative in the present experiment, indicating that the vertical way of transmission is a rare event.

O objetivo deste trabalho foi avaliar a associação dos polimorfismos dos genes bGH, IGF-1 e PIT-1 com características de peso e ganho de peso numa população F2 de bovinos (Gir x Holandês), pela técnica de PCR-RFLP. As freqüências alélicas A e B, do gene PIT-1, e dos genótipos AA, AB e BB, nas populações parentais foram semelhantes entre si, mas diferentes das freqüências nas populações cruzadas F1 e F2, para esse gene. Quanto ao gene bGH, os animais da raça Holandesa apresentaram freqüência de 100% para o alelo E e os animais da raça Gir, 92% para o alelo F, resultando em alta freqüência de indivíduos heterozigotos nas populações F1 e F2. Quanto ao gene IGF-1, todos os animais da raça Holandesa eram heterozigotos (AB) e, nos animais Gir, a maioria dos indivíduos foi de homozigotos (AA), o que resultou em alta freqüência do alelo A nas populações F1 e F2. Foram encontradas associações significativas do alelo A do gene PIT-1 com as características de peso aos 60, 205, 365 dias e ganho de peso do nascimento aos 60 dias. Em bGH, observou-se efeito significativo do alelo E para peso aos 365 dias e ganho de peso do nascimento aos 60 dias, enquanto o efeito do alelo A do IGF-1 foi significativo somente para peso ao nascimento. Os alelos identificados podem ser usados como marcadores no melhoramento animal.

The objective of this work was to evaluate the association between polymorphisms of bGH, IGF-1 and PIT-1 genes with weight and weight gain traits in a bovine F2 population derived from Holstein x Gyr crosses, using the PCR-RFLP technique. Allelic frequencies A and B of PIT-1 gene and AA, AB, and BB genotypes were similar between parental populations but different from F1 and F2 crossed populations. For the bGH gene, Holstein animals showed allelic frequency of 100% for E allele, while Gyr animals showed allelic frequency of 92% for F allele, resulting in high frequency of heterozygous animals in F1 and F2 populations. For the IGF-1 gene, all Holstein were heterozygous (AB) and most Gyr were homozygous (AA), resulting in a high frequency of A allele in F1 and F2 populations. Significant associations were found between PIT-1 allele A with traits weight at 60, 205 and 365 days and weight gain from birth to 60 days. For IGF-1, significant association was found between A allele and birth weight. For bGH gene, significant associations were found between E allele and 365 days weight and weight gain from birth to 60 days. The selected alleles could be used as markers in animal breeding for these traits.