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Eimeria spp. are the pathogen that causes coccidiosis, a significant disease that affects intensively reared livestock, especially poultry. Anticoccidial feed additives, chemicals, and ionophores have routinely been employed to reduce Eimeria infections in broiler production. Therefore, the shift to antibiotic-free and organic farming necessitates novel coccidiosis preventive strategies. The present study evaluated the effects of potential feed additives, liver free and chitosan, against Eimeria tenella infection in White Leghorn broiler female chickens. One hundred sixty-five 1-day-old White Leghorn broiler female chicks were divided into 11 groups (15 female chicks per group), including the positive control group (G1), the negative control group (G2), a chitosan-treated group (G3), a chitosan-treated-infected group (G4), the liver free-treated group (G5), the liver free-treated-infected group (G6), the liver free-and-chitosan-treated group (G7), the liver free-and-chitosan-infected group (G8), the therapeutic liver free-and-chitosan-treated-infected group (G9), the sulfaquinoxaline-treated group (G10), and the sulfaquinoxaline-treated-infected group (G11). Chitosan was fed to the chicks in G3 and G4 as a preventative measure at a dose of 250 mg/kg. The G5 and G6 groups received 1.5 mg/kg of Liverfree. The G7 and G8 groups received chitosan and Liverfree. The G10 and G11 groups were administered 2 g/L of sulfaquinoxaline. From the moment the chicks arrived at Foshan University (one-day-old chicks) until the completion of the experiment, all medications were given to them as a preventative measure. G8 did; however, receive chitosan and liver free as therapeutic supplements at 7 dpi. The current study showed that the combination of liver free and chitosan can achieve better prophylactic and therapeutic effects than either alone. In E. tenella challenged chickens, G8 and G9 chickens showed reduced oocyst shedding and lesion score, improved growth performance (body weight, body weight gain, feed intake, feed conversion ratio, and mortality rate), and cecal histology. The current study demonstrates that combining liver free and chitosan has superior preventive and therapeutic benefits than either alone, and they could also be used as alternative anticoccidial agents. [ABSTRACT FROM AUTHOR]

We studied the serovars present and the performance of two selective plating media, Hektoen enteric agar (HE) and Xylose-Lysine-Desoxycholate (XLD) agar, as well as the time of tetrathionate broth incubation (one and five days) used for Salmonella isolation in different samples of egg and egg packs collected from supermarkets in Argentina. We also determined the occurrence of bacterial growth inhibitors in egg content and the antibiotic resistance profile of the isolated strains. Salmonella spp. was detected in 29 samples (1.8%) from 1,643 different types of egg and egg pack samples analyzed. Eight serovars of Salmonella were isolated: S. ser. Typhimurium (ST), S. ser. Enteritidis (SE), S. ser. Agona, S. ser. Westhampton, S. ser. Brandenburg, S. ser. Gallinarum (biovar Gallinarum), S. ser. Muenchen, and S. ser. Montevideo. The most frequent were ST and SE; both were present in eggshells, yolk, and albumen. The increase in the incubation time in tetrathionate broth affected the isolation of Salmonella spp. from eggshell and pool of yolk and albumen with different values of relative sensitivity and accuracy (p<0.05). Furthermore, there was a significant difference between the two-plating media at the time of tetrathionate broth incubation in eggshell for the relative sensitivity (p<0.05). The agreement between XLD and HE agar in relation to the time of tetrathionate broth incubation depended on the type of samples studied. The occurrence of bacterial growth inhibitors in yolk and albumen depended on bacteria assayed. However, these were presented in yolk and albumen from the same pool of egg content. There were 2 and 8 different patterns of resistance among Salmonella strains isolated, and 87% of these strains were multidrug-resistant. It is necessary to understand the epidemiology of Salmonella from eggs and to alert public health to minimize the prevalence of antibiotic resistance of Salmonella spp. in Argentina. [ABSTRACT FROM AUTHOR]

Metabolomics is a bottom-up approach to studying metabolism in living cells, tissues, organoids, or even whole organisms. In conjunction with genomics and proteomics, it is a crucial tool for better understanding complex biological systems. In comparison to genomics or proteomics, metabolomics more directly reflects the phenotype since it encompasses events that occur downstream of gene expression. In the field of poultry or avian diseases, this method is now well established, although it could have more innovative applications in the future. For example, 13Cguided metabolomics and flux analysis could be used to identify biochemical pathways associated with heat or immune stress. It could also help to explore the effects of alternatives to antimicrobials on the intestinal health of poultry and their action on avian pathogens, including the mechanisms of resistance and persistence. In this review, we discuss some basic principles of metabolomics and its current and potential applications in poultry. [ABSTRACT FROM AUTHOR]

Simple Summary: Heat stress is a growing concern in broiler production due to increasing environmental temperatures. Little is known about the effects of heat stress on the natural immune system defenses and health of broiler chickens. Using an environmental heat stress model in combination with minimally invasive tissue sampling techniques, the local and systemic, acute inflammatory responses to intradermal injection of bacterial component lipopolysaccharide or sterile saline (injection control) were examined in broilers reared in cyclic heat-stress- or thermoneutral-temperature conditions. This study revealed suppressive effects of heat stress on inflammatory responses initiated by lipopolysaccharide and by the sterile saline injection. Specifically, at the site of LPS injection, heat stressed broilers had lower infiltration of inflammatory leukocytes, reactive oxygen species generation, and expression of inflammatory factors than thermoneutral control broilers. Additionally, in the blood, concentrations of inflammatory leukocytes and plasma acute phase proteins did not increase in heat-stressed broilers like in thermoneutral broilers. Moreover, heat-stressed broilers had lower baseline concentrations of circulating lymphocytes than thermoneutral broilers. Hence, broilers reared in cyclic heat stress conditions have impaired ability to respond to bacterial challenges and associated tissue damage. To assess effects of environmental heat stress (HS) on the local and systemic inflammatory responses to lipopolysaccharide (LPS), broilers were reared under thermoneutral (TN) or cyclic HS conditions. Thermoneutral temperatures followed commercial production settings, with HS broilers exposed to 35 °C for 14 h/day from 4 days onward. At 37 days, HS- and TN-broilers were assigned to either LPS (100 μg/mL) or endotoxin-free phosphate-buffered saline (PBS; vehicle) treatments, eight each to HS- and TN-LPS, four each to HS- and TN-PBS. Treatments were administered by intradermal injection of growing feather (GF) pulps; 10 μL/GF; 12 GF/broiler. Blood and GF were collected before and at 6 and 24 h post-injection to assess leukocyte population changes in GF-pulps and blood, reactive oxygen species (ROS) generation and cytokine expression in GF-pulps, and plasma concentrations of alpha-1 acid glycoprotein (AGP-1). HS-LPS broilers had lower (p ≤ 0.05) infiltration of heterophils and macrophages, ROS generation, and inflammatory cytokine expression in GF-pulps, and lacked the increases in heterophil, monocyte, and plasma AGP-1 concentrations observed in TN-LPS broilers. HS-broilers had similar or greater drops in blood lymphocytes 6 h post-LPS or -PBS injection, respectively, and lower baseline levels (p ≤ 0.05) of circulating T- and B-lymphocytes than TN-broilers. Results indicated that cyclic HS reduced the local and systemic acute inflammatory responses to LPS in broilers, likely impairing their innate defense against microbial infection. [ABSTRACT FROM AUTHOR]

Moringa oleifera (MO), a cultivated species of the Moringa, is known for its high concentration of essential nutrients that promote growth. To assess its impact on rabbits' gut morphometric, behavioural, and physiological parameters, a study was conducted using sixty growing male white New Zealand rabbits at 40 days old. The rabbits were divided into four groups and supplemented with dried MO leaves at varying levels (0%, 0.5%, 1% and 2% of body weight) for four weeks. The results revealed significant increases in organ weights, such as liver and intestinal length, and the height of intestinal villi and crypt depth in the large intestine. The muscular layer's and submucosa's thickness also increased in different parts of the intestine in rabbits fed with MO compared to the control group. No significant effect was observed on the caecum mucosa depth. Interestingly, no significant differences were found in body weight or weight gain between the Moringa supplementation groups and the control group. However, rabbits offered 0%, 0.5% and 1% MO spent more time feeding and resting than those given 2% MO. The grooming and sniffing percentage remained unaffected by Moringa supplementation. Regarding blood parameters, rabbits that received MO leaves in their diet showed improvements in red blood cell count, haemoglobin levels, packed cell volume, white blood cell count, neutrophil count, total protein, globulin, and A/G ratio. Moreover, there was a significant decrease in malondialdehyde levels and an increase in glutathione and high‐density lipoprotein levels, indicating an antioxidative effect. Overall, the study concluded that MO leaves supplementation in the rabbit diet positively influenced the rabbits' health by modulating the immune system, improving histological aspects of the intestine, liver, and spleen, and enhancing physiological parameters through its antioxidative properties. [ABSTRACT FROM AUTHOR]