Serum biochemical profile of emus (Dromaius novaehollandiae) reared in captivity

Serum Biochemistry of Greater Rhea (Rhea americana) in Captivity in the Northeast of Brazil

We investigated the biochemical profile of greater rheas (Rhea americana) in captivity and correlated these values according to the birds' sex. A total of 69 serum samples were collected from a breeding site in Mossoró, northeastern Brazil, and analyzed to quantify serum biochemical parameters (total protein, albumin, cholesterol, calcium, phosphorus, uric acid, urea, creatinine, ALP, AST, and CK). The birds had levels of urea, creatinine, total cholesterol, aspartate aminotransferase, calcium, and phosphorus similar to the values reported for ratite and ostrich species. By sex, females showed higher values (p < 0.05) of calcium (3.5 mmol/L), total cholesterol (7.5 mmol/L), and uric acid (435.3 μmol/L) than males, which had 3.1 mmol/L, 3.8 mmol/L, and 390.7 μmol/L, respectively. This can be attributed to the difference in diet, the productive phase of females, or stress at the time of sampling. The data present a wide spectrum of biochemical results regarding the health of greater rheas, contributing to the veterinary clinical practice of this species.

Microplastic Ingestion Induces Size-Specific Effects in Japanese Quail

Plastic pollution can pose a threat to birds. Yet, little is known about the sublethal effects of ingested microplastics (MP), and the effects of MP < 1 mm in birds remain unknown. This study therefore aimed at evaluating the toxicity of environmentally relevant polypropylene and polyethylene particles collected in the Norwegian coast in growing Japanese quail (Coturnix japonica). Birds were orally exposed to 600 mg MP over 5 weeks, covering small (<125 μm) and large (3 mm) MP, both separately and in a mixture. We evaluated multiple sublethal endpoints in quail, including oxidative stress, cytokine levels, blood-biochemical parameters, and reproductive hormones in blood, as well as body mass. Exposure to small MP significantly induced the activities of the antioxidant enzymes catalase, glutathione-S-transferase, and glutathione peroxidase. Exposure to large MP increased the levels of aspartate aminotransferase (liver parameter) and decreased 17β-estradiol levels in females. Body mass was not directly affected by MP ingestion; however, quail exposed to small MP and a mixture of large and small MP had a different growth rate compared to control quail. Our study used similar levels of MP as ingested by wild birds and demonstrated size-dependent effects of MP that can result in sublethal effects in avifauna.

Post mortem changes in M. iliotibialis lateralis muscle protein profile of emu (Dromaius novaehollandiae)

The available literature lacks information on the metabolic processes taking place in emu muscles after the cessation of circulation. Hence, this study was undertaken to examine the physicochemical characteristics (pH, drip loss, WHC, TBARS, L*, a*, b*) with concomitant changes in protein expression patterns (SDS-PAGE) of femoral muscle (M. iliotibialis lateralis) that occur post mortem and during the first days (0 h, 24 h, 48 h) of its maturation in 1- and 3-year-old emus. Our results indicated that the interaction between emus age and storage time had significant impact on meat pH and all color indicators. Furthermore, we detected 24 differentially expressed protein bands, representing 22 different gene products. ClueGO pathways analysis revealed that these proteins were mainly involved in glycolysis/gluconeogenesis pathway, pyruvate metabolism and pyrophosphate hydrolysis-driven proton transmembrane transporter activity. Based on the results obtained it can be assumed that early post-mortem metabolism of emu muscle is predominantly based on the glycolysis as reflected by the relative abundance alterations of the glycogenolytic and glycolytic enzymes. Moreover, the energy supplies provided by ATP and other high-energy substances degradation is higher in the group of older emus. Our findings also highlighted the complexity of the molecular mechanisms underlying the conversion of muscle to meat.