Animals最新文献

Fasting and refeeding systems can cause significant short-term fluctuations in nutrient and energy levels, triggering adaptive physiological responses in animals. This study examines the effects of fasting and refeeding on blood biochemical indicators and transcriptional profiles in the hypothalamus and subcutaneous adipose tissue of geese. Biochemical assays reveal that fasting significantly increases levels of free fatty acids and glucagon, while reducing concentrations of triglycerides, leptin, and insulin. Transcriptomic analyses identify a complex transcriptional response in both the hypothalamus and subcutaneous adipose tissue, affecting several metabolic pathways and key genes associated with feed intake and energy metabolism. In subcutaneous adipose tissue, fasting downregulates genes involved in fatty acid synthesis (LPL, SCD, and ACSL1) and upregulates PLIN2, a gene promoting lipid droplet degradation. Fasting affects a variety of metabolic pathways and critical genes in the hypothalamus, including Apelin, insulin, and mTOR signaling pathways. After fasting, the mRNA expression of NOG, GABRD, and IGFBP-1 genes in the hypothalamus are significantly upregulated, while proopiomelanocortin (POMC) gene expression is markedly downregulated. This study highlights the intricate biological responses to nutritional changes in geese, which adds to our understanding of energy balance and metabolic regulation in avian species.

The increase in acarological risk of tick bites is significantly driven by profound changes in landscape, which alter the density and distribution of wildlife that support tick populations. As a result of habitat shifts and land abandonment, which create environments conducive to tick proliferation, the risk of disease transmission to humans and animals is increasing. In this context, it is important to explore tick ecology by applying a comprehensive methodology. In this study, we examined the relationship between wildlife temporal occupancy and tick abundance in two distinct regions: an alpine hunting district and a natural park in the Apennines. For each sampling point, we calculated wildlife temporal occupancy from camera trap pictures and estimated ticks' abundance from dragging transects in the area immediately surrounding camera traps. In modelling the relationship between those two variables, we included abiotic factors such as saturation deficit, normalized difference vegetation index, and altitude. Results show the importance of altitude and wildlife temporal occupancy (itself related to different habitat and land management characteristics) on the ecology of questing ticks. If employed in management decisions for natural environments, such information is useful to modulate the acarological risk and thus the risk of tick-borne pathogens' transmission.

Wild boar (Sus scrofa) is the most widespread member of the order Artiodactyla, a group of even-toed ungulates that are prone to overabundance, with adverse consequences for conservation, agriculture, transportation and public health [...].

In the present study, Asian seabass (Lates calcarifer, Bloch) fingerings were used as an animal model to investigate the toxicological effects of zinc oxide nanoparticles (ZnO NPs) under 5 ppt estuarine conditions. The fish were exposed to 0, 1, 5 or 50 ppm ZnO NPs for 8 weeks. It was found that ZnO NP concentrations of 5-50 ppm negatively affected several growth rate parameters, such as the weight and total length of the fish. Additionally, 5 and 50 ppm ZnO NPs led to 32.55% and 100% mortality, respectively, after 8 weeks after exposure (WAE). Furthermore, compared with the control, exposure to 1-50 ppm ZnO NPs strongly affected hematological indices, such as total blood cells, red blood cells, leukocytes and hematocrit, and suppressed lysozyme activity, superoxide anion production and bactericidal activity. High Zn concentrations accumulated in the head kidney, gills and liver, whereas low levels were detected in the gut, skin and muscle. Expression analysis of immune-related genes via quantitative real-time RT-PCR revealed that 5 and 50 ppm ZnO NPs significantly upregulated the cc and cd4 genes at 1 WAE. In contrast, 50 ppm ZnNPs downregulated the expression levels of the cd8, cc, hsp70, hsp90, tcrα, lyz and igmh genes at 1 WAE (p < 0.05). Finally, at 8 WAE, histopathological analysis revealed that 5 and 50 ppm ZnO NPs severely induced alterations in the head kidney, gills and liver.

The study investigated fish welfare at slaughter. Killing animals may induce suffering to the animals even under the best available technical conditions. Moreover, fish have different physiological characteristics and are slaughtered differently from terrestrial animals. The use of commercially available methods exposes farmed fish to pain and suffering during slaughter, which could lead to acute stress and post mortem changes in fish quality. The study aimed to discuss (i) the current knowledge and knowledge gaps on fish welfare related to stunning and killing methods; (ii) the variables that affect the post mortem changes in fish meat, and (iii) the indicators of welfare during slaughter. Application of welfare protocols at slaughter improves fish welfare. Specific protocols for fish are not provided in EC Regulation 1099/2009 on animal protection at killing. Detailed guidelines in the fish welfare assessment may allow the development of specific fish legislation. Developing humane technologies might have important effects on fish quality, consumer perception and aquaculture economics.

In this study, the influence of fasting on hepatic glucose and lipid metabolism was explored by examining biochemical, antioxidative, and morphological indicators and transcriptional expression in the liver of javelin goby (Synechogobius hasta) after 0, 3, 7, or 14 days of starvation. Marked reductions in hepatic glycogen and triglycerides occurred from the seventh day of starvation until the end of the trial (p < 0.05). However, no alterations in hepatic cholesterol or protein were detected throughout the entire experiment (p > 0.05). During fasting, the activities of pyruvate kinase, lactate dehydrogenase, and glycogen phosphorylase a all rose firstly and then fell (p < 0.05). The activities of hepatic fatty acid synthase and acetyl-CoA carboxylase were minimized to their lowest levels at the end of food deprivation (p < 0.05), while lipase was elevated after 7-14 days of fasting (p < 0.05). Catalase, glutathione, and the total antioxidative capacity were increased and maintained their higher values in the later stage of fasting (p < 0.05), whereas malondialdehyde was not significantly changed (p > 0.05). Hepatic vein congestion, remarkable cytoplasmic vacuoles, and irregular cell shape were present in S. hasta which endured 3-7 days of fasting and were less pronounced when food shortage was prolonged. In terms of genes associated with glucose and lipid metabolism, the hepatic phosphofructokinase gene was constantly up-regulated during fasting (p < 0.05). However, the mRNA levels of glycogen synthase and glucose-6-phosphatase were obviously lower when the food scarcity extended to 7 days or more (p < 0.05). Fatty acid synthase, stearoyl-CoA desaturase 1, and peroxisome proliferator-activated receptor γ were substantially down-regulated in S. hasta livers after 7-14 days of food deprivation (p < 0.05). However, genes involved in lipolysis and fatty acid transport were transcriptionally enhanced to varying extents and peaked at the end of fasting (p < 0.05). Overall, starvation lasting 7 days or more could concurrently mobilize hepatic carbohydrates and fat as energy resources and diminished their hepatic accumulation by suppressing biosynthesis and enhancing catabolism and transport, ultimately metabolically and structurally perturbing the liver in S. hasta. This work presents preliminary data on the dynamic characteristics of hepatic glucose and lipid metabolism in S. hasta in response to starvation, which may shed light on the sophisticated mechanisms of energetic homeostasis in fish facing nutrient unavailability and may benefit the utilization/conservation of S. hasta.

Haploid embryonic stem cells (ESCs), which combine the properties of haploidy and pluripotency, hold significant potential for advancing developmental biology and reproductive technology. However, while previous research has largely focused on haploid ESCs in freshwater species like Japanese medaka (Oryzias latipes), little is known about their counterparts in marine species. This study hypothesizes that haploid ESCs from marine fish could offer unique insights and tools for genetic and virological research. To address this, we successfully established and characterized a novel haploid ESC line, hMMES1, derived from marine medaka (Oryzias melastigma). The hMMES1 cells contain 24 chromosomes, exhibit core stem cell characteristics, and express key pluripotency markers. In vitro, hMMES1 cells form embryonic bodies (EBs) capable of differentiating into the three germ layers. In vivo, hMMES1 cells were successfully transplanted into marine medaka and zebrafish, resulting in the generation of interspecies and interordinal chimeras. Additionally, hMMES1 cells demonstrate high efficiency in transfection and transduction, and show susceptibility to major aquaculture viruses, nodavirus (NNV) and iridovirus (SGIV). These findings suggest that hMMES1 cells represent a valuable model for genetic manipulation and virological studies in marine fish species.

Effective antimicrobial stewardship (AMS) is crucial for combating the rise of antimicrobial resistance (AMR), particularly in veterinary medicine. Educational programs targeting veterinary students can play a significant role in shaping their knowledge and attitudes toward antimicrobial use and stewardship. This study aimed to evaluate the impact of educational programs on the knowledge and attitudes regarding AMS among veterinary students in Serbia. A structured educational program on AMS was implemented for veterinary students at the Faculty of Agriculture, University of Novi Sad. Pre- and post-symposium assessments were conducted to measure changes in students' knowledge and attitudes. The study employed a mixed-methods approach, including surveys and focus groups, to gather quantitative and qualitative data. The study resulted in significant short-term improvements in students' knowledge of AMS principles and their attitudes toward responsible antimicrobial use. Participants demonstrated a better understanding of the mechanisms of resistance and the importance of adhering to stewardship guidelines. Qualitative feedback indicated increased awareness of the consequences of inappropriate antimicrobial use and a stronger commitment to applying stewardship practices in their future careers. The educational programs effectively enhanced immediate veterinary students' knowledge and attitudes regarding AMS. These findings underscore the importance of integrating targeted educational programs into veterinary curricula to promote responsible antimicrobial use and combat resistance in veterinary practice.

Duck hepatitis A virus type 1 (DHAV-1) is the main pathogen causing viral hepatitis in ducks, marked by high contagion and acute mortality. Live attenuated DHAV-1 vaccines are widely used to control the disease. This study aims to develop a mismatch amplification mutation assay (MAMA)-PCR for the rapid detection and differentiation of Korean DHAV-1 wild-type strains from vaccine strains. A MAMA primer was designed to target a single nucleotide polymorphism (SNPs) at position 2276 within the VP1 gene, allowing differentiation in a single PCR reaction. The MAMA-PCR accurately identified both strains, with detection limits of 10^0.5 ELD₅₀/mL and 10^2.3 ELD₅₀/mL, respectively. The MAMA-PCR demonstrated specificity, showing no cross-reactivity with 12 other viral and bacterial pathogens. The MAMA-PCR was applied to 89 farms, yielding results consistent with nested-PCR and sequence determination, identifying four positive farms for DHAV-1 vaccine strains. In conclusion, this study is the first to employ the MAMA-PCR method to distinguish between DHAV-1 wild-type and vaccine strains. The developed method is rapid, simple, specific, and sensitive, thereby serving as an effective tool for clinical diagnostics in identifying and differentiating between Korean DHAV-1 wild-type and vaccine strains.

This paper focuses on the problem of numeracy when writing regulations, specifically how to describe a threshold for crowding of pigs during transport, considering transported pigs range in body mass from 5 to 500 kg. When scientific findings provide the basis for regulation in the public interest, those findings must be communicated in a consistent way to regulators and policymaking bodies. Numeracy is the ability to understand, reason with, and apply appropriate numerical concepts to real-world questions. Scientific understanding is almost always based on rational understanding of numerical information, numeracy. The threshold of administrative offenses is often a numerical description. Commercial livestock transporters have an interest in loading livestock compartments to the maximum to achieve the largest payload allowed by axle weight laws, as is the case in all bulk commodity transport. Maximizing payload minimizes costs and environmental hazards of fuel exhaust and can benefit the public with lower pork prices, but has a serious animal welfare risk. Livestock production academics, veterinarians, and animal welfare activists have been working for decades to determine the level of livestock crowding in transport containers that would be appropriate for regulatory enforcement. The scientific discourse has been plagued by a lack of numerical standardization when describing results of trials and forming recommendations. Exceeding specific numerical thresholds is the core to implementing enforcement actions. This paper examines the communication and other barriers that have prevented emergence of a consensus on this question and provides a direction toward resolution. Further confirmation of effects of crowding livestock in transit is needed. This paper suggests that articulating an enforceable standard in pig transport is possible. In inspection for compliance, discovering the LP₅₀ (lethal pressure-50) for slaughter-weight pigs is an initial global benchmark goal. The LP₅₀ is the loading floor pressure in a commercial transport compartment, under field conditions, that would result in the death of at least one pig in the group 50% of the time.