The thyroid gland is a highly vascularized organ in vertebrates. However, the information on the vascular pattern of this gland in pigs remains limited. This study elucidates the morphoanatomy and arterial supply of the gland in three breeds: Landrace (L), Large White (W), and Crossbreed (LWD). Two hundred twelve pigs were used and dissected to observe the arteries supplying blood to the gland. As a result, the gland was classified into three types based on its appearance: pear-shaped, butterfly-shaped, or partially separated. Moreover, the arteries supplying the gland were observed and then compared among breeds. The arterial supply of the thyroid gland on the cranial side consisted of branches from the cranial laryngeal artery, cranial thyroid artery, superficial cervical artery, and common carotid artery. Otherwise, the caudal side was supplied by the caudal thyroid artery, superficial cervical artery, bicarotid trunk, internal thoracic artery, and external thoracic artery. Furthermore, significant differences were identified between L and LWD, as well as between W and LWD, in the pattern of arterial origin on the cranial right side of the thyroid gland. Similarly, on the left side, significant differences were observed not only between L and W but also between W and LWD. On the caudal side, significant differences were found between L and W, as well as between W and LWD. These anatomical variations provide important insights for research and clinical applications involving the thyroid gland in pigs.

Branching patterns of the adrenal artery exhibit interspecies and individual variations. As Eulipotyphla species have distinctive morphological characteristics, observations in this group may provide insights into the comparative anatomy of this artery. This study used 15 house musk shrews (Suncus murinus). In most cases, adrenal arteries arose from a single parent artery, namely the caudal phrenic artery, abdominal aorta, or renal artery. In one left case, adrenal arteries emerged from both the abdominal aorta and renal artery. The most common pattern of adrenal arterial supply was one middle and one caudal adrenal artery on both sides, with no cranial one. The house musk shrew exhibited a simpler branching pattern than other species, offering comparative anatomical insights into the adrenal artery.

Mastitis is one of the most common diseases in dairy cows, causing significant economic losses due to reduced productivity and the need for treatment. In recent years, MRSA (methicillin-resistant Staphylococcus aureus) has emerged as an important cause of chronic and recurrent mastitis, posing additional challenges for herd health management. The aim of this study was to conduct a comparative analysis of recurrent mastitis in Holstein-Friesian cows caused by MRSA and non-MRSA S. aureus, with a particular focus on the number of recurrences, somatic cell count (SCC), milk production, and risk factors. The study included 120 cows, divided into two groups of 60, raised under identical conditions on a single farm. Milk samples were collected under sterile conditions, cultured on Blood agar and Mannitol Salt agar, and analyzed for the presence of MRSA using PCR for the mecA gene. Cows were monitored for the number of recurrences, SCC, daily milk yield, and response to therapy. Statistical analyses included t-tests, ANOVA, correlation analysis, and logistic regression. The results showed that MRSA-infected cows had significantly higher recurrence rates, along with elevated SCC and reduced milk yield compared to the non-MRSA group. MRSA was identified as the strongest independent risk factor for mastitis recurrence. These findings highlight the importance of regular bacteriological monitoring, appropriate therapy, and preventive measures to reduce economic losses and protect herd health.

The interaction between gut bacteria and their host is vital for the early diagnosis and treatment of disease in captive animals. Here, we report a 16S rRNA sequencing-based bacterial profile during the progression of cardiovascular disease and drug treatment in a captive giant panda (Ailuropoda melanoleuca). We observed changes in the composition of bacteria associated with inflammation and regulating nutrient metabolism. Predicted metabolic functions also exhibited alterations. The remarkably reduced gut microbiome diversity, along with the imbalance in community interaction networks, indicated possible gut dysfunction. Our findings represent the first description of gut bacterial changes in a giant panda with cardiovascular disease. Maintaining symbiotic bacteria diversity is crucial for preventing health issues in captive animals and advancing wildlife conservation efforts.

European foulbrood, caused by Melissococcus plutonius, is a major bacterial disease of honey bee brood. Although strains belonging to the genetically related group known as clonal complex 12 (CC12) are highly virulent, their virulence factors remain unclear. Since tyramine has been proposed as a putative virulence factor, we constructed a knockout mutant of the putative tyrosine decarboxylase gene (tdc) from a CC12 strain to assess its role in pathogenicity. The tdc knockout mutant lost the ability to produce tyramine, confirming that tdc is responsible for tyramine production. However, the mutant showed no attenuation in virulence toward honey bee brood. These results suggest that tyramine production is not essential for the pathogenicity of CC12 strains in European foulbrood.

Hepatic copper accumulation is assessed qualitatively via histopathology, and hepatic copper concentration is measured quantitatively. Laparoscopic biopsy provides samples adequate for histopathology; however, its suitability for copper quantification in cats remains unclear. Liver tissue samples from 19 cats undergoing laparoscopic liver biopsy were evaluated for hepatic copper score and concentration. Copper scores were determined by a board-certified pathologist using rhodanine-stained sections. Hepatic copper concentrations were determined using atomic absorption spectrometry, and the rhodanine-positive pixel ratio was calculated from histological images using ImageJ. Copper-associated hepatopathy was identified in three cats: two with a score of 4 and one with a score of 5. Seven cats demonstrated cholangiohepatitis (scores 0–3). The hepatic copper score was significantly correlated with copper concentration in the 19 cats (Spearman’s r=0.757, P<0.001). Rhodanine-positive pixel ratio also correlated with copper concentration (Spearman’s r=0.668, P<0.01). Therefore, laparoscopic biopsy provides feline liver tissue feasible for qualitative and quantitative copper analysis. The liver rhodanine-positive pixel ratio offers a useful quantitative alternative when hepatic copper concentration cannot be measured in cats.

Inflammation suppresses erythropoiesis, leading to non-regenerative anemia in dogs. Currently, clinical evidence of this inhibitory effect remains limited. This study provides important clinical insight by demonstrating a negative correlation between C-reactive protein (CRP) concentration and reticulocyte count over time in dogs with inflammatory anemia. This study aimed to leverage inflammatory anemia as a model to examine the longitudinal relationship between CRP levels and reticulocyte counts in dogs. Medical records of 23 dogs diagnosed with various inflammatory conditions and persistently non-regenerative erythropoiesis were retrospectively reviewed. Serial results of hematological and serological parameters were analyzed using linear mixed-effects models to account for intra- and inter-individual variation. Reticulocyte counts in anemic dogs with resolving underlying inflammatory conditions were significantly negatively correlated with CRP levels (standardized β=−0.53, 95% confidence interval (CI) −0.68 to −0.37; P<0.001). Moreover, cross-sectional analysis revealed that higher CRP levels were significantly associated with lower reticulocyte counts, suggesting that the severity of inflammation may be linked to reduced reticulocyte counts (Pearson’s r=−0.5; P=0.01). Similarly, erythropoietic responses to darbepoetin alfa appeared to be attenuated in dogs with elevated CRP concentrations. In these dogs, whose mean CRP concentration was 6.15 mg/dL, the onset of reticulocytosis was delayed approximately twofold, and the increase in peak reticulocyte count was approximately 38% lower than that in dogs with normal CRP concentrations. This study provides clinical evidence supporting an association between systemic inflammation and reduced or delayed reticulocytosis in dogs, highlighting the clinical utility of concurrently monitoring CRP and reticulocyte levels to assess disease progression and inflammatory recovery.

Serum amyloid A (SAA) is a major acute-phase protein in cats; however, the agreement between commercially available feline SAA assays has not been fully evaluated. This study compared two analytical systems: the FUJI DRI-CHEM vf-SAA (sandwich fluorescence immunoassay) and VET-SAA Eiken (immunoturbidimetry). Eighty residual plasma samples from client-owned cats were analyzed. Methods were compared using Spearman’s correlation, Passing–Bablok regression, and Bland–Altman percentage difference analysis. These assays revealed a strong association (Spearman’s ρ=0.948). Passing–Bablok regression indicated proportional and constant bias (y=0.3325x + 1.155), and Bland–Altman analysis demonstrated a large negative mean percent difference (−86.2%). These findings suggest that the results are not interchangeable and method-specific reference intervals may be required.

The incidence of enzootic bovine leukosis, which is due to bovine leukemia virus (BLV), has been increasing in Japan. However, large-scale surveys have not been conducted in recent years, and the impact of cattle harboring high BLV proviral loads on within-farm BLV prevalence remains unclear. To clarify the situation, questionnaires and PCR and serological testing for BLV were conducted between 2022 and 2024 on 95 beef breeding farms (3,082 cattle) and 9 Japanese Black fattening farms (140 cattle) in the Tohoku region. We also examined the effects of various factors on within-farm proportions of BLV-positive cattle. The proportions of PCR-positive and seropositive cattle were 34.3% and 35.9% in beef breeding cattle and 15.7% and 15.0% in Japanese Black fattening cattle, respectively. Among the 74 farms with at least one PCR-positive animal, the proportion of PCR-positive cattle was significantly higher on farms with at least one animal with a high proviral load (≥400 copies/10 ng DNA) than on farms without any such cattle. Similarly, farms where high-proviral-load cattle accounted for≥10% of the herd had significantly higher proportions of PCR-positive cattle. In addition, farms that used public pastures, practiced on-farm grazing, or had experienced enzootic bovine leukosis within the past 5 years had significantly higher proportions of PCR-positive cattle. These findings suggest that BLV prevalence in beef cattle in the Tohoku region remains comparable to that reported approximately 10 years ago, indicating that BLV transmission in this region may be under control. Furthermore, cattle with high proviral loads may adversely affect within-farm BLV prevalence, indicating that targeted control measures focusing on such animals are essential for effective BLV control.

This retrospective study investigated the bacterial species distribution and antimicrobial susceptibility of canine ocular isolates submitted to a Japanese diagnostic laboratory between October 2022 and March 2026. A total of 737 isolates were recovered, with Staphylococcus pseudintermedius (248/737, 33.6%) and Streptococcus canis (116/737, 15.7%) the most common isolates. Notably, 100 (40.3%) of the S. pseudintermedius isolates were methicillin-resistant. Cefotaxime demonstrated high activity against major Gram-positive pathogens, except for methicillin-resistant S. pseudintermedius, and Escherichia coli. In contrast, susceptibility to gatifloxacin varied markedly among the species, whereas the spectrum of gentamicin and polymyxin B was limited due to intrinsic resistance among common Gram-positive pathogens. These findings provide useful information for empirical antimicrobial selection in canine ocular infections in Japan.

Understanding the underlying issues related to animal transport is essential for promoting animal welfare. However, no research has focused on the transport process and its physiological effects on spent layer breeder chickens. Therefore, this study aimed to investigate a single commercial transport process in spent layer breeder chickens and evaluated its physiological and behavioral effects across three strains of focal hens: Sakura, Lohmann Julia (Julia), and Hy-Line Brown (Brown). A total of 1,611 chickens (1,547 hens and 64 roosters, aged 700 days) including various crossbreeds and lineages were transported over 32.9 km in 55 min. The total mortality rate was 0.25%. Each chicken was sequentially housed in two transport crate types and remained there until shackling. The maximum duration from initial capture to shackling was 7 hr 30 min. Temperatures inside cages and crates were higher than ambient conditions. Transported focal hens showed reduced body weight and elevated heterophil-to-lymphocyte ratios. Brown hens exhibited higher heterophil-to-lymphocyte ratios and lower core body temperatures compared to the overall mean. Additionally, transported focal hens exhibited wet plumage, shivering, and piloerection due to rain exposure, although temperatures near them remained within their thermal comfort zone. These findings reveal the complexity of the transport process and its adverse effects on spent layer breeder chickens, highlighting genetic differences among strains in physiological and behavioral responses. They also underscore the need for careful animal monitoring, preventing wetting, and adopting strain-specific transport management practices to improve animal welfare.

Porcine circovirus type 2 (PCV2) is the major causative agent of porcine circovirus-associated disease. We investigated the dynamics of maternally derived anti-PCV2 antibodies (MDA) in 40 piglets born to five healthy, unvaccinated sows on a Japanese swine farm. Anti-PCV2 antibody levels were measured by ELISA from birth to 19 days of age and analyzed together with serum total protein and IgG concentrations. Data were stratified by sow, and uncertainty was estimated using sow-cluster bootstrap analysis. The S/P ratio increased after colostrum intake, peaked at 1–3 days of age, and then declined exponentially until day 19. These findings characterize pre-vaccination anti-PCV2 MDA kinetics and indicate that serum total protein at birth may reflect passive immune status.

Canine pulmonary adenocarcinoma (CPAC) is a rare, aggressive tumor with no established prognostic molecular biomarkers. The expression of monocarboxylate transporter 4 (MCT4) and glucose transporter 1 (GLUT1), key glycolysis-related proteins, is induced by hypoxia and is generally associated with poor prognosis in human pulmonary adenocarcinoma; however, their clinical significance in dogs remains unclear. This study investigated the expression of MCT4 and GLUT1 in 61 CPAC cases. Immunohistochemistry revealed significantly higher MCT4 and GLUT1 expression in tumors compared with normal lung tissues. High expression of both proteins was associated with lymph node metastasis. Kaplan–Meier analysis showed that high MCT4 expression was associated with prolonged overall survival, while GLUT1 showed no prognostic impact. However, MCT4 was not retained as an independent prognostic factor in multivariable Cox proportional hazards analysis. These results suggest that MCT4 and GLUT1 are upregulated in CPAC and may have distinct biological and clinical significance compared with human pulmonary adenocarcinoma.

The glottis of 26 dogs with respiratory signs was examined by virtual laryngoscopy for peering into the throat from within the trachea (RDVL: rostral direction virtual laryngoscopy) with and without sedation of butorphanol, medetomidine, and alfaxalone (BMA). These dogs are divided into two groups of with or without sedation. In 9 unsedated dogs, there were many Chihuahuas, and the primary symptom was coughing. In 17 sedated dogs, Toy Poodles and Pomeranians were the most common breeds, and the primary symptoms were coughing and worsening respiratory symptoms at excitement. RDVL provided a reliable view of glottic motion, and the airway space was interfered with for flaccid adductors. RVDL without sedation is recommended. However, BMA sedation is suggested when necessary.

Serological monitoring of infectious diseases in laboratory rodents is vital for ensuring animal health. Therefore, we have previously developed a multiplex immunochromatographic assay (ICA) to detect antibodies against six pathogens as follows: mouse hepatitis virus, Sendai virus, and Clostridium piliforme (Tyzzer’s disease) in mice, and Seoul type orthohantavirus, Sendai virus, and sialodacryoadenitis virus in rats. However, the preparation of these strips is time-consuming and labor-intensive. Therefore, this study aimed to determine the long-term storage conditions for the developed multiplex ICA strips. The multiplex ICA strips stored in the polyethylene zipper-sealed bags (poly_bags) at −30°C maintained detectable reactivity for all six targeted pathogens for 36 months, regardless of the presence or absence of desiccants, oxygen absorbers, or a vacuum state. However, when stored at 18–28°C (room temperature) and 4°C, the detectable reactivity of the multiplex ICA strips stored in poly_bags was reduced for some of the six targets pathogens at 18 months after storage. This reduction was not prevented by the storage with the desiccants and in the vacuum-sealed poly_bags (vacuum_bags). The oxygen absorber reduced detectability of the multiplex ICA strips. These results indicate that storing ICA strips in poly_bags at −30°C, which is a simple method, is able to maintain detectability long-term for the strips format and pathogen targets examined in this study.

The clinical, histological, and immunohistochemical features of 26 fibrous proliferative lesions in the vagina of 14 female dogs (13 intact and 2 neutered) were examined. These lesions presented as nodular or pedunculated masses. Histopathological examination revealed that all lesions consisted of spindle- and stellate-shaped cells with mild atypia, collagenous stroma, and blood vessels. Mitotic figures were rare. The number of blood vessels was significantly greater in pedunculated masses than in nodular masses. Immunohistochemically, spindle- and stellate-shaped cells were positive for progesterone receptor in all 26 lesions, estrogen receptor in 5 of 26 lesions, desmin in 20 of 26 lesions, and α-smooth muscle actin (αSMA) in 8 of 26 lesions. Lesions in neutered dogs exhibited lower progesterone receptor expression and higher estrogen receptor expression than those in intact females. No significant differences in desmin or αSMA expression were observed between the two groups. These findings suggest that the fibrous proliferative lesions in the canine vagina described in this study may represent progesterone-associated benign proliferative changes composed of myofibroblasts.

Ductal tumors of canine mammary glands can be difficult to distinguish from simple tumors on routine histology. Because oxytocin receptor (OXTR) expression in myoepithelial cells has been implicated in human breast tumorigenesis, we immunohistochemically evaluated 8 ductal adenomas and 5 ductal carcinomas, including OXTR expression. Luminal cells were positive for cytokeratin 19 and pan-cytokeratin. Suprabasal myoepithelial cells were strongly positive for p63, weakly and focally positive for vimentin, and negative for smooth muscle actin and calponin, therefore indicating that p63 is the most suitable marker for these cells in ductal tumors. Unlike humans, OXTR was expressed in luminal cells of normal canine mammary ducts and in both luminal and suprabasal myoepithelial cells in ductal tumors, suggesting a role in ductal tumor development.

A captive male Japanese raccoon dog died after self-mutilation by biting its tail and developing anorexia. At necropsy, ulceration of the tail root and pelvic region, an abdominal mass, multifocal nodules in the lungs, and thrombi in the heart were observed. Histopathological examinations revealed multifocal pyogranulomatous inflammation in the lungs, abdominal mass, spleen, brain, liver, and kidneys. Gram-positive bacterial aggregates were observed in the lungs, abdominal mass, and spleen. These organisms were partially acid-fast and periodic acid-Schiff-positive, and branching filaments were observed on Grocott’s methenamine silver staining. Nocardia aobensis was identified in the abdominal mass by PCR and sequence analysis. These findings suggest that N. aobensis should be considered a potential cause of disseminated pyogranulomatous disease in animals.

The Na⁺/Ca²⁺ exchanger (NCX) is a key regulator of intracellular Ca²⁺ homeostasis, mediating bidirectional ion transport in response to electrochemical gradients. NCX plays essential roles in diverse physiological processes, including cardiac contraction, neuronal signaling, and hormone secretion, while its dysregulation is implicated in a wide range of pathophysiological conditions such as heart failure, ischemia, and neurodegenerative diseases. Recent advances in structural biology, particularly cryo-electron microscopy, have provided detailed insights into the molecular architecture of eukaryotic NCX, revealing the mechanisms underlying ion transport, regulation, and inactivation. These studies have highlighted the functional importance of conserved structural elements, including the α1- and α2-repeats and cytosolic regulatory domains, in governing exchanger activity. In parallel, pharmacological studies have identified a variety of NCX modulators with distinct mode and isoform selectivity. While classical inhibitors predominantly target the reverse mode, emerging compounds—including highly selective inhibitors and novel activators—demonstrate diverse mechanisms of action, often involving allosteric modulation rather than direct interaction with the ion-binding site. This review integrates current knowledge of NCX structure, function, and pharmacology, with a particular focus on the relationship between structural determinants and transport mode selectivity. We also discuss the challenges that have limited the clinical translation of NCX-targeting drugs and outline future perspectives for the rational design of next-generation NCX modulators.

Ticks harbor diverse Rickettsia spp., including several spotted fever group rickettsiae of veterinary and public health importance. However, information on tick-associated Rickettsia spp. in Zambia remains geographically limited. In this retrospective molecular survey, we examined 1,587 individual ticks collected from vegetation and domestic animals in eight provinces of Zambia during 2016–2018. Ticks were identified morphologically and screened for Rickettsia spp. by PCR targeting the citrate synthase gene (gltA). Representative gltA positive samples were further characterized by sequencing of ompA, ompB, htrA, sca4, and the 16S rRNA gene. In total, 204 ticks (12.9%) were tested positive for gltA and detected in all eight provinces examined. Sequencing of gltA revealed 26 sequence variants, of which 25 clustered within the spotted fever group and one belonged to transitional group rickettsiae. Multilocus phylogenetic analysis identified sequence variants related to recognized or putative tick-borne rickettsiae, including R. africae, R. conorii, R. massiliae, R. aeschlimannii, Candidatus R. jingxinensis, Candidatus R. rhabdomydis, and R. hoogstraalii. These findings indicate that ticks in Zambia harbor genetically diverse Rickettsia lineages and provide a geographically broad molecular baseline for future surveillance, isolation attempts, and genomic characterization of tick-borne rickettsiae in the region.

A 5-month-old Munchkin cat was referred for hematuria. Computed tomographic angiography revealed hepatic arteriovenous malformation (HAVM) within the left lateral liver lobe and multiple acquired portosystemic shunts (APSSs), in addition to a bladder calculus. Following medical management, the cat underwent attenuation of arterioportal communications. Because ligation of the left hepatic artery did not normalize portal pressure, the left hepatic division was resected. Surgical ligation of a subset of the APSSs was performed 1 month later. Postoperatively, clinical signs improved, hepatopetal portal flow was restored, and biochemical liver function parameters normalized. The remaining APSSs regressed spontaneously. To our knowledge, based on the English-language literature, this is the first reported case of feline or canine HAVM in which liver function parameters normalized.

A 5-year-old Poodle presented with a plantigrade stance three weeks after traumatic gastrocnemius tendon rupture. Surgical exploration confirmed a complete rupture; following debridement and tenorrhaphy, a 20 mm defect remained. This gap was bridged using a double-layer ultra-high-molecular-weight polyethylene (UHMWPE) suture tape and augmented with flexor digitorum lateralis (FDL) transposition. At 2 months, ultrasonography confirmed maintained tendon continuity without foreign body reaction. By 3 months, posture normalized and gait analysis showed near-symmetric hindlimb loading. No major complications occurred during the 12-month follow-up. Combined UHMWPE bridging and FDL augmentation is an effective surgical option for chronic gastrocnemius ruptures with substantial defects when primary apposition is not feasible.

Fesaviruses, members of the group of picorna-like viruses, were discovered in 2014 in stool samples from cats in an animal shelter in the United States. In this study, we investigated the serological evidence of fesavirus 4 infection in domestic cats in Japan using a purified recombinant antigen corresponding to a portion of the large open reading frame of fesavirus 4. An enzyme-linked immunosorbent assay was developed and used to test 100 cat plasma samples to detect specific antibodies against the fesavirus 4 antigen and Western blotting confirmed presence of specific antibodies against the fesavirus 4 antigen in 12 samples. These findings highlight the importance of investigating newly discovered viruses circulating in companion animals in Japanese animal shelters.

Long-term monitoring of viruses and Varroa destructor within the same honey bee colonies is rare in Japan. Thus, we conducted a 4-year fixed-point survey of three Apis mellifera colonies in Tokyo with monthly screening for seven viruses (using polymerase chain reaction) and Varroa infestation. Deformed wing virus was detected year-round, whereas sacbrood virus and black queen cell virus peaked in spring and summer. Israeli acute paralysis virus appeared sporadically, without seasonal trends. Varroa infestation rates (monitored during the latter 2.5 years) did not correlate with the number of detected virus types and showed no seasonality. Although viral load was not quantified, this long-term dataset provides valuable baseline data on local virus dynamics, providing baseline information on seasonal virus dynamics in managed honey bee colonies in Tokyo.

Various aspects of movement, excavation, ecology, and muscle structure of Gymnophiona species have been reported. However, the unique mechanisms and dynamics of peristaltic locomotion and excavation are unclear, particularly for soil-inhabiting Gymnophiona spp. Previous studies primarily focused on forward locomotion and thrusting behavior, with less attention paid to the underlying vertebral and muscular mechanisms. Herein, using X-ray computed tomography, video analysis, and tissue specimens, we determined that the Mexican caecilian (Dermophis mexicanus) could generate peristaltic locomotion via coordinated bending and extension of the vertebral column and associated musculature, including the M. dorsalis trunci, M. subvertebralis, and external muscular sheath, facilitating both forward and backward movement. Thrust forces akin to a multistep spring mechanism are generated by extending their twisted and bent spines across the head, neck, chest, and abdomen. Each region flexes its vertebrae and modulates muscle size to fulfill various functions. The spinous processes of the vertebrae are loosely connected to independent segmental annuli via tendons. Unlike snakes, caecilians can move forward and backward by bending and stretching their spinal columns within their bodies, allowing movement through soil when there is space for their heads and bodies, which confers remarkable survival advantages. Dorsoventral and right–left dynamics of the spinal and muscular structures and the locomotion of Mexican caecilians was confirmed.

The African grey parrot (Psittacus erithacus) is endangered due to habitat loss, poaching, and illegal trade. In 2022, Chubu University and the Uganda Wildlife Education Centre–Conservation Area (UWEC-CA) have initiated an ex-situ conservation project for rehabilitation and future reintroduction. Noninvasively genetic sampling was conducted using feces from four parrots at UWEC-CA and naturally shed feathers from 22 parrots at 11 Japanese zoos. Non-invasive genetic sampling enabled reliable sex identification and mitochondrial sequencing of parrots in Uganda and Japan. Phylogenetic analysis revealed two major clades, including a Gabon-associated lineage within which all UWEC-CA parrots clustered, providing baseline genetic context relevant to ex-situ conservation management and evidence-based reintroduction.

This study investigated the timing of puberty and seasonal changes in spermatogenesis in raccoons (n=156) from Wakayama Prefecture. In the 0-year class, testis size, weight, and seminiferous tubule diameter increased in winter, although only a few raccoons were sexually mature. Most raccoons in the 1-year class attained sexual maturity by autumn–winter of their second year. In the ≥2-year class, testicular activity regressed during summer. Spermatogenesis scores were used to assess age-dependent spermatogenic development. Logistic regression indicated that testes with epididymides ≥19.1 mm in size and ≥9.6 g in weight corresponded to a 50% predicted probability of the presence of morphologically mature spermatozoa. These findings provide region-specific indices of male reproductive cycles in raccoons.