Sudden outbreak of metastatic intestinal adenocarcinoma in rainbow trout Oncorhynchus mykiss.

Intestinal adenocarcinomas are uncommon in fishes. To date, they have been reported in zebrafish Danio rerio, blue gularis Fundulopanchax sjostedti, koi carp Cyprinus carpio koi, Atlantic salmon Salmo salar and rainbow trout Oncorhynchus mykiss. Metastases are even rarer and have been observed so far at very low prevalence, only in feed-induced adenocarcinoma in Atlantic salmon and rainbow trout. Intestinal adenocarcinoma with liver and heart metastases and mesenteric invasion was found in approximately 33% of 4 yr old rainbow trout from a Slovene hatchery with 2000 breeding trout. During stripping, lumps in the abdominal cavity were palpated in one-third of the breeding fish; some of the fish were anorectic and lethargic, and mortality was slightly increased. Affected trout were euthanized and 4 were submitted for necropsy and histopathology. Necropsy revealed firm, whitish, irregularly lobular masses originating from the intestine. Histologically, the intestinal masses showed a prominent proliferation of tall columnar neoplastic epithelial cells arranged in dense irregular islands or solid areas and papillotubular protuberances. Solid areas of neoplastic cells were also observed in the mesentery of all trout and in the liver of one trout, whereas minute groups of neoplastic cells were seen in the vessels of the intestinal mucosa in all trout and in the myocardium and the liver of one trout. Epithelial origin of neoplastic cells was confirmed by expression of the cytokeratin marker AE1/AE3. The intestinal masses were diagnosed as intestinal adenocarcinoma with mesenteric invasion and metastases to the liver and heart. The cause of intestinal adenocarcinoma was not determined.

Seminiferous epithelium cycle staging based on the development of the acrosome in ram testis.

Testicular histopathology is considered the most sensitive and reliable method to detect the effects of chemicals on sperm production. To carry out a sensitive examination of testicular histopathology and interpret the changes require knowledge of spermatogenic stages. Spermatogenic staging based on acrosome development during spermiogenesis is conventionally performed in animal species routinely used for research and toxicity testing. In contrast, small ruminants, such as sheep and goats, are rarely used as animal models to evaluate toxicity in male reproductive organs. To the best of our knowledge, a comparable spermatogenic staging system in rams has not yet been fully characterised. Hence, this study aimed to adapt the existing spermatogenic staging based on acrosome development in bull testes to fit the seminiferous epithelium cycle of ram testes. The results show that spermatogenic staging based on acrosome development in bull testes can, with slight modifications, be efficiently used for the staging of ram testes.

Determination of free and total bisphenol A in the urine and feces of orally and subcutaneously dosed sheep by high-performance liquid chromatography with fluorescence detection.

An analytical procedure has been introduced to enable a study of the excretion of free bisphenol A (BPA), total BPA and its main metabolite bisphenol A glucuronide (BPA-GLUC). In the experiment, in which 100 µg/kg b. w. BPA was administered daily to one Istrian Pramenka sheep for 5 days with consecutive urine and feces samples being taken, BPA and total BPA were determined in samples using high-performance liquid chromatography (HPLC) with fluorescence detection. Because of their good recovery, precision, and sensitivity, the methods have also proved applicable to further ecotoxicological studies of free BPA, BPA-GLUC and total BPA. The results were subsequently compared with reported field studies of BPA in livestock excreta.

Bisphenol A in edible tissues of rams exposed to repeated low-level dietary dose by high-performance liquid chromatography with fluorescence detection.

The presented work deals with levels and distribution of bisphenol A (BPA) in the edible tissues of a large food-producing animal species. An experimental animal study included 14 young Istrian pramenka rams (Ovis aries), of which seven were exposed for 64 days to a low dietary dose of BPA at 25 µg/kg b.w./day, and seven served as a control group. Residue analysis of both aglycone and total BPA was performed in the muscle tissue, liver, kidney and fat tissue of the individual animals by means of enzymatic deconjugation (for total BPA), organic solvent extraction, molecularly imprinted polymer solid-phase extraction (MISPE) clean-up and high-performance liquid chromatography with fluorescence detection (HPLC-FLU). The analysis was optimized and validated for aglycone BPA in the fat tissue and for the total BPA in all tissues investigated. Edible tissues of the control group of rams generally remained BPA-free, while there were concentration differences between the control and treated groups for liver and kidney post last administration. The human health risk resulting from this study was assessed by the estimated dietary exposure in adults, which was < 0.1% related to the valid European Union Tolerable Daily Intake (TDI) value of 4 µg/kg b.w./day. However, it would be 58-fold higher than the newly proposed TDI value of 0.04 ng/kg b.w./day.

Experimental Exposure to Bisphenol A Has Minimal Effects on Bone Tissue in Growing Rams-A Preliminary Study.

Bisphenol A (BPA) is a well-known synthetic compound that belongs to the group of endocrine-disrupting chemicals. Although bone tissue is a target for these compounds, studies on BPA-related effects on bone morphology in farm animals are limited. In this preliminary study, we investigated the effects of short-term dietary BPA exposure on femoral morphology, metabolism, mineral content, and biomechanical behavior in rams aged 9-12 months. Fourteen rams of the Istrian Pramenka breed were randomly divided into a BPA group and a control group (seven rams/group) and exposed to 25 µg BPA/kg bw for 64 days in feed. Blood was collected for determination of bone turnover markers (procollagen N-terminal propeptide, C-terminal telopeptide), and femurs were assessed via computed tomography, histomorphometry, three-point bending test, and mineral analysis. BPA had no significant effects on most of the parameters studied. Only mineral analysis showed decreased manganese (50%; p ≤ 0.05) and increased copper content (25%; p ≤ 0.05) in the femurs of BPA-exposed rams. These results suggest that a 2-month, low-dose exposure to BPA in growing rams did not affect the histomorphology, metabolism, and biomechanical behavior of femurs; however, it affected the composition of microelements, which could affect the histometric and biophysical properties of bone in the long term.

Basic Exploratory Study of Bisphenol A (BPA) Dietary Administration to Istrian Pramenka Rams and Male Toxicity Investigation.

Bisphenol A (BPA), an endocrine-disrupting chemical and environmental pollutant, has been reported by many researchers to induce male reproductive toxicity in different experimental models. In this study, we investigated whether long-term exposure for two months to 25 µg/kg body weight (low dose) of BPA affects spermatogenesis or sperm quality in young Istrian Pramenka rams exposed via diet. We evaluated body and testicular weights, histopathology of testes and epididymides, and sperm analyses, and compared these parameters between the group of treated rams and the control group of rams. Although there were some differences between the two groups, these differences were not large or statistically significant. The only statistically significant difference was the lower epithelial height of seminiferous tubules in treated rams, compared to control rams. In addition to assessing toxicity, BPA concentrations in the blood plasma of treated rams were determined after the first administration, and the toxicokinetic parameters of total BPA were calculated. In this study, no major signs of altered reproduction in rams were detected.

A rapid analysis of Bisphenol A using MISPE coupled with HPLC-FLD in tissues of food-producing animals.

Bisphenol A (BPA) is a highly-produced organic compound of anthropogenic origin with a wide-range use and is ubiquitously present in both living organisms and the environment. A previously published analytical method for testing of the free (aglycone) BPA in foodstuffs was simplified and optimized for sheep muscle tissue, kidney and liver, by using only a single MISPE purification step allied with HPLC-FLD analysis. The recovery rates and RSD values over a concentration range of 1-10 µg/kg were in the range of 67‒86% and 3‒34%, respectively, while linearity in the matrix, represented by the r2, was ≥0.999. LOD values were 0.5‒1 µg/kg and LOQ values were 1 µg/kg. The analytical method used is a contribution to the field of veterinary toxicology and food testing and also proved to be applicable for other food-producing animal species, e.g. pigs, poultry and freshwater fish. The MISPE sorbent material for testing of BPA was reusable, with up to five re-use cycles without significant loss in performance characteristics.•The paper reports on a rapid determination of free (aglycone) BPA in tissues of food-producing animals by HPLC-FLD and presents a substantial improvement of analytical performance with regard to time- and cost-savings, as well as environmental protection.•MISPE is an advanced analytical technology, and the results proved that in a single and simplified SPE step it had good performance characteristics such as selectivity, recovery and precision, allied with low LOD and LOQ values.•It was proved that MISPE BPA cartridges could be used at least five times without significant loss of methodological recovery and precision.

Preliminary toxicokinetic study of BPA in lactating dairy sheep after repeated dietary and subcutaneous administration.

Dietary intake is the predominant route of human exposure to bisphenol A and one of the important food commodities is milk. The aim of our study was to preliminarily evaluate the bisphenol A exposure and disposition in sheep milk after repeated dietary and subcutaneous administration of a relatively low dose (100 µg/kg of b. w./day) of bisphenol A to a sheep. On the basis of blood plasma sampling, milk sampling and HPLC analysis, we developed the toxicokinetic model. With the toxicokinetic model we showed that most likely only free bisphenol A passes into the mammary gland and is subsequently conjugated there. The percentage of the dose eliminated with milk was less than 0.1%, regardless of the route of bisphenol A administration. It is proven that the bisphenol A is eliminated through the milk of lactating sheep. However, the amounts excreted in the milk that were detected in this study are minimal.

The first detection and whole genome characterization of the G6P[15] group A rotavirus strain from roe deer.

Although rotaviruses have been detected in a variety of host species, there are only limited records of their occurrence in deer, where their role is unknown. In this study, group A rotavirus was identified in roe deer during a study of enteric viruses in game animals. 102 samples of intestinal content were collected from roe deer (56), wild boars (29), chamois (10), red deer (6) and mouflon (1), but only one sample from roe deer was positive. Following whole genome sequence analysis, the rotavirus strain D38/14 was characterized by next generation sequencing. The genotype constellation, comprising 11 genome segments, was G6-P[15]-I2-R2-C2-M2-A3-N2-T6-E2-H3. Phylogenetic analysis of the VP7 genome segment showed that the D38/14 rotavirus strain is closely related to the various G6 zoonotic rotavirus strains of bovine-like origin frequently detected in humans. In the VP4 segment, this strain showed high variation compared to that in the P[15] strain found in sheep and in a goat. This finding suggests that rotaviruses from deer are similar to those in other DS-1 rotavirus groups and could constitute a source of zoonotically transmitted rotaviruses. The epidemiological status of group A rotaviruses in deer should be further investigated.