The Eastern spot-billed duck ( Anas zonorhyncha ) is a common migratory waterfowl widely distributed throughout East Asia. However, the lack of species-specific reference intervals, defined as the normal range of values derived from a healthy population for clinical interpretation, hampers accurate health assessment and clinical diagnostics in this species. This is further complicated by hematologic characteristics of avian blood, such as nucleated red blood cells and thrombocytes, which pose challenges to conventional automated measurement systems optimized for mammals. This study aimed to establish hematological and biochemical reference intervals for juvenile Eastern spot-billed ducks and to evaluate the accuracy of an automated hematology analyzer (XN-1000V, Sysmex, Japan), which newly supports avian blood analysis, compared to traditional manual counting methods. Blood samples were collected from 55 clinically healthy juvenile ducks. The established reference intervals were largely consistent with those reported in related Anas species, though Eastern spot-billed ducks exhibited a heterophil-predominant leukogram. No significant differences were observed between sexes. Comparison between manual and automated methods revealed statistically significant differences in most hematological parameters; however, most of these differences were not clinically relevant, except for thrombocyte counts. Moderate correlations were found for key parameters, including WBC, RBC, hemoglobin, PCV, and MCV, suggesting potential clinical applicability of the automated analyzer with some limitations. This study provides the first species-specific hematologic and biochemical reference intervals for juvenile Eastern spot-billed ducks under semi-captive conditions, offering valuable baseline data for clinical assessments in this subset of the population. Additionally, it highlights the need for further optimization of XN-1000V analyzers for reliable and precise application in avian diagnostics.

Sungryong Kim, Sungin Lee, Ok-Joo Lim, Ki-Jeong Na, Dong-Hyuk Jeong. J Vet Clin 2022;39:411-6. https://doi.org/10.17555/jvc.2022.39.6.411

The long-tailed goral (Naemorhedus caudatus) is classified as an endangered species globally, and national projects for conservation are underway in South Korea. However, blood test references would enable comprehensive health assessments in this species. This study provides reference intervals for hematology, biochemistry, and blood gas analysis in long-tailed goral for health assessments and to aid conservation strategies. Blood test data from 75 gorals managed between 2016 and 2020 were analyzed to establish reference intervals and to examine the influence of age and sex on hematological and biochemical parameters, as well as differences between arterial and venous blood in blood gas analysis. Significant age-related differences (p < 0.01) were observed in MCH, lymphocyte count, platelet count, total cholesterol, HDL cholesterol, ALT, amylase, creatinine, calcium, and inorganic phosphorus. Sex-related differences were found in lymphocyte count, total cholesterol, HDL cholesterol, ALT, and amylase. Blood gas analysis showed significant differences in pO₂, SO₂, and lactate between arterial and venous samples. This retrospective study provides statistical reference intervals for hematology, biochemistry, and blood gas analysis in clinically healthy long-tailed gorals, which is particularly valuable for endangered wildlife where obtaining an adequate number of specimens is challenging.