The influence of eugenol, benzocaine and ice water on the welfare of adult grass carp (Ctenopharyngodon idella).

The aim of this study was to evaluate the effects of eugenol, benzocaine, and ice water during the sedative, anesthetic or euthanasia processes on the welfare of adult grass carp (Ctenopharyngodon idella). The experimental design was randomized and the animals were divided into eight groups. Sixty-two animals underwent an acclimation period. The neutral group used to obtain basal data of grass carp were not subjected to treatments, but anesthetized to collect blood samples and euthanized by medullary section. The others seven groups were submitted to seven treatments with eight repetitions (control group; ethanol; eugenol 50 mgL-1, eugenol 250 mgL-1, benzocaine 100 mgL-1, benzocaine 300 mgL-1, and ice water 2:1), their behavior was observed. Blood samples was collected and then euthanized by medullary sectioning. Biometric data were measured and a part of the liver was collected for hepatic glycogen analysis. There was a statistically significant difference in the time required to reach the anesthetic stage between the groups (p < 0.01). Benzocaine and eugenol at the higher concentration provided the fastest responses to sedatives and anesthetics, respectively. The animals subjected to higher anesthetic concentrations reached stage five and did not return from anesthesia, therefore, benzocaine and eugenol were effective euthanizing agents. Benzocaine at the lowest concentration showed the highest concentrations of glucose and cortisol (p < 0.05). Although benzocaine at 100 mgL-1 concentrations is widely used as an anesthetic in fish, this study demonstrated its use as a stressor agent. Basal data of grass carp for stress parameters are presented for the first time.

Escherichia coli ST224 and IncF/blaCTX-M-55 plasmids drive resistance to extended-spectrum cephalosporins in poultry flocks in Parana, Brazil.

Resistant Enterobacterales of avian intestinal origin can contaminate carcasses during broiler processing and thereby spread through the human food chain. This study aimed at assessing the prevalence, diversity and genomic characteristics of ESBL/AmpC Enterobacterales in poultry flocks from different farms and cities in the state of Paraná, Brazil. Enterobacterales isolated from cloacal samples were subjected to antimicrobial susceptibility testing (AST). ESBL/AmpC isolates were whole-genome sequenced and subjected to S1-nuclease pulsed-field gel electrophoresis (S1-PFGE) followed by Southern blotting to determine the location of resistant genes on plasmids. A surprisingly high proportion of E. coli (40.6 %) collected on non-selective plates presented an ESBL/AmpC phenotype. Multidrug resistance was statistically not higher in ESBL/AmpC E. coli having the potential to be Avian Pathogenic (APEC-like) compared to non-APEC-like ESBL/AmpC E. coli isolates. Resistance to antibiotics not authorized for use in poultry in the State of Paraná was observed, suggesting that antimicrobial resistance (AMR) is co-selected by the use of veterinary-licensed antibiotics. Phylogenetic analyzes revealed the presence of identical or highly similar ESBL/AmpC E. coli clones on farms distant up to 100 km of each other; this strongly suggests that the centralization and verticalization of the poultry industry can facilitate the spread of resistant bacteria among different farms, companies, and cities. The molecular characterization of clones and plasmids proved the dominance of the ST224 E. coli lineage and the IncF/blaCTX-M-55 plasmid, possibly indicating the emergence of successful clones and plasmids adapted to the chicken host. Our data contribute to the epidemiological tracking of resistance mechanisms in Enterobacterales from poultry and to knowledge for further One Health studies to control the spread of resistant bacteria from food animals to humans.

Intake and performance of growing lambs supplemented with quebracho tannins.

Tannins can modulate rumen fermentation and increase the bypass protein; however, the use of different doses and sources of condensed tannins (CT) in animal diets has divergent results. The aim of this study was to evaluate the effect of different levels of dietary quebracho extract inclusion, as a CT source, in the performance and carcass characteristics of growing lambs. Forty-eight weaned lambs (Texel, Suffolk, and Hampshire Down crossbred) were homogenously blocked into four groups and supplemented at 0, 10, 30, and 60 g tannins/kg dry matter intake (DMI) (CONT, T1%, T3%, and T6%, respectively). The DMI, the roughage to concentrate ratio, the feed conversion rate (FCR), the average daily gain (ADG), and the body condition score (BCS) were evaluated. After the trial, animals were slaughtered, and the cold carcass weight, carcass yield, and subcutaneous fat thickness (SFT) were determined. Higher levels of CT in T3% and T6% reduced (P < 0.001) the total DMI and intake of concentrate without impacting (P = 0.071) the roughage intake (% body weight). ADG was the lowest for T6%, although the total weight gain and BCS were the lowest also for T3% (P < 0.001). FCR was worst for T6% (P < 0.001). Regarding carcass characteristics, T6% had the lowest weight of carcass (P = 0.003) and SFT (P = 0.021) compared to CONT. Carcass yields were similar among all the groups (P = 0.247). T1% did not differ from CONT to any parameter (P > 0.05). Supplementing quebracho CT at a low dose did not show beneficial effects; moreover, higher doses of CT led to detrimental effects in intake and animal performance.

Non-conventional cultures and metabolism-derived compounds for bioprotection of meat and meat products: a review.

Meat and meat products are important nutritional sources for humans; however, they are highly susceptible to pathogenic or spoilage bacteria, which leads to economic losses for the industry and has become a public health threat. Several biological methods have been developed to promote meat safety and to increase shelf life, mostly focusing on lactic acid bacteria from the genera Lactobacillus and Pediococcus. However, little attention has been paid to other groups of microorganisms with potential use as bioprotective cultures. This review aims to discuss the potential use of non-conventional microorganisms and biometabolites for bioprotection in meat and meat products. This review covers recent research involving the use of non-conventional microorganisms to improve the quality and safety of meat products. Bacteria that are often overlooked also have the potential for use in the food industry, either by direct application or by using their metabolites in the product itself or the development of intelligent packaging systems. Hopefully, this review will instigate new studies on emerging biological methods to ensure the safety of food and protect the health of consumers.