Haematological and serum biochemical reference values in Chinese water deer (Hydropotes inermis): a preliminary study

Interactions Between Heavy Metal Exposure and Blood Biochemistry in an Urban Population of the Black Swan (Cygnus atratus) in Australia

There is growing recognition of the threat posed to wildlife by pollutants. Waterbirds are robust bioindicators of ecosystem health, and metal toxicity is a threat to these species in waterways worldwide. Urban waterbirds are likely to be at the highest risk of heavy metal exposure, but this issue has not been widely explored in Australia. Our aim was to estimate contemporary heavy metal exposure in a sedentary urban waterbird population: black swans (Cygnus atratus) inhabiting an inner-city wetland in one of Australia's largest cities, Melbourne. To investigate the physiological implications of legacy heavy metal exposure in these birds, we quantified blood biochemistry profiles and examined their relationships with metal concentrations in feathers. We caught 15 swans in 2021 and took feather samples to measure the concentration of eight heavy metals (chromium (Cr), manganese (Mn), iron (Fe), nickel (Ni), copper (Cu), zinc (Zn), lead (Pb), and mercury (Hg)), and blood samples to measure the concentration of 13 plasma analytes. Multivariate regression analysis revealed few associations between heavy metals and biochemistry markers, and no differences between sexes or age classes. This study presents a baseline dataset of these contaminants and blood biochemical profiles of swans at this wetland that can be used for future monitoring and is an important step toward a better understanding of the threat posed by heavy metals to Australian urban waterbirds.

Haematological and chosen biochemical parameter assessment of the antioxidant system in red deer (Cervus elaphus) blood in early and late pregnancy

Introduction

The aim of this study was to investigate changes in haematological parameters and the antioxidant system in the early and late pregnancy of red deer (Cervus elaphus).

Material and Methods

Blood samples were collected from 30 red deer females 50 days after impregnation and 40 days before calving. Complete blood counts and stained blood smears were assessed. Paraoxonase 1 (PON1), superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR) activities, glutathione disulphide (GSSG), total glutathione, total bilirubin, total protein, albumin, uric acid, malondialdehyde (MDA), beta-hydroxybutyrate (BHB), low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides, cholesterol levels and total antioxidant status (TAS) were measured.

Results

The haematological characteristics of blood collected in the third trimester showed higher haemoglobin levels, haematocrit, mean corpuscular volume (P < 0.05) and a lower mean cell haemoglobin concentration (P < 0.05) in comparison to samples collected on the 50^th day after mating. Activity of CAT and MDA, LDL, and triglyceride levels were lower while GR, GSSG, total glutathione, total protein and BHB levels were increased in blood samples drawn in the third trimester compared with the first trimester blood samples. There were no changes in SOD, PON1 activities, TAS, bilirubin, albumin, HDL, cholesterol or uric acid concentrations.

Conclusion

Red deer’s compensatory mechanisms facilitate its optimal adaptation to seasonal changes evidenced by mild pronounced haematological disturbances and an effective antioxidant system during pregnancy.

Effect of heat stress on vital and hematobiochemical parameters of healthy dogs

Background and Aim:

Heat stress is a major challenge for animals, impairing their welfare and performance. This study aimed to determine the effect of heat stress on the vital and hematobiochemical parameters of healthy dogs.

Materials and Methods:

The experimental subjects comprised 10 dogs, encompassing seven males and three non-pregnant females between 2 and 3 years of age. Ambient temperature (AT) and relative humidity (RH) were recorded 2 hourly during the day and the temperature humidity index was calculated. Vital parameters [i.e., rectal temperature (RT), respiratory rate, and heart rate (HR)] were assessed and blood was collected from each dog daily for hematobiochemical analysis.

Results:

The RT (38.5±0.2°C) of dogs exposed to high AT and high RH (HA/HR) conditions was significantly (p<0.05) higher than that of dogs exposed to HA and low RH (LR) conditions (37.2±0.11°C). Under HA/HR conditions, packed cell volume, hemoglobin concentrations, and white blood cell counts were significantly lower than those of the same dogs exposed to HA/LR conditions. Conversely, under HA/HR conditions, the lymphocyte, monocyte, eosinophil, alanine aminotransferase, aspartate aminotransferase, and cortisol values were significantly higher (p<0.05) than the values obtained in dogs exposed to HA/LR conditions. Meanwhile, the alkaline phosphatase, urea, and glucose levels were significantly lower (p<0.05) in dogs exposed to HA/HR conditions.

Conclusion:

The exposure of healthy dogs to HA/HR conditions induced heat stress, which may have an adverse effect on their immune status, thereby affecting their health and welfare.

Early Embryo Exposure to Assisted Reproductive Manipulation Induced Subtle Changes in Liver Epigenetics with No Apparent Negative Health Consequences in Rabbit

Embryo manipulation is a requisite step in assisted reproductive technology (ART). Therefore, it is of great necessity to appraise the safety of ART and investigate the long-term effect, including lipid metabolism, on ART-conceived offspring. Augmenting our ART rabbit model to investigate lipid metabolic outcomes in offspring longitudinally, we detected variations in hepatic DNA methylation ART offspring in the F3 generation for embryonic exposure (multiple ovulation, vitrification and embryo transfer). Through adult liver metabolomics and proteomics, we identified changes mainly related to lipid metabolism (e.g., polyunsaturated fatty acids, steroids, steroid hormone). We also found that DNA methylation analysis was linked to changes in lipid metabolism and apoptosis genes. Nevertheless, these differences did not apparently alter the general health status. Thus, our findings suggest that ART is likely to be a player in embryo epigenetic events related to hepatic homeostasis alteration in adulthood.