A single exposure to sub-lethal concentrations of a glyphosate-based herbicide or fluoxetine-based agent on growth performance in Nile tilapia

The aim of the present study was to determine e whether a single acute 96 hr exposure of a glyphosate-based herbicide (GBH) to Nile tilapia fingerlings affected growth performance during the first 90 days of culture. This association was considered as GBH increases serotoninergic activity that affect fish anorexically. Although these findings were based upon chronic investigations, this study was designed to examine whether a single, acute, but excessive concentration GBH might impair growth performance in fish. In parallel, fish were also exposed to fluoxetine (FLU), a drug that selectively inhibits the reuptake of serotonin in brain synapses, leading to increased serotoninergic activity. Data demonstrated a decreased growth performance in fingerlings exposed to GBH or FLU compared to unexposed fingerlings. In fact, FLU-exposed fingerlings exhibited lower average weight and length, diminished weight gain, which resulted in lower final biomass. GBH-exposed fish, despite displaying a lower mean body weight, exhibited a biomass similar to biomass on controls. These body weight differences were noted after 30-60- and 90-day growth period in clean water. In an aquaculture context, these observed changes may be considered harmful to the production or economic performance of large-scale farming as currently practiced in tilapia farming.

Stimulants cocktail: Methylphenidate plus caffeine impairs memory and cognition and alters mitochondrial and oxidative status

Methylphenidate (MPH) is a psychostimulant widely misused to increase wakefulness by drivers and students. Also, MPH can be found in dietary supplements in a clandestine manner aiming to burst performance of physical exercise practitioners. The abusive use of high doses of caffeine (CAF) in these contexts is equally already known. Here, we demonstrate the behavioral, oxidative and mitochondrial effects after acute exposure to high doses of MPH (80 mg/L) and CAF (150 mg/L), alone or associated (80 mg/L + 150 mg/L, respectively). We used zebrafish as animal model due to its high translational relevance. We evaluated the behavioral effects using the Novel Tank Test (NTT), Social Preference Test (SPT) and Y-maze Task and analyzed biomarkers of oxidative stress and activity of mitochondrial respiratory chain complexes. MPH alone induced antisocial behavior. MPH inhibited lipid peroxidation. The association of MPH + CAF presented memory impairment and anxiogenic behavior. In oxidative status, it inhibited lipid peroxidation, increased protein carbonylation and mitochondrial complex II, III and IV activity. Our results demonstrate that MPH and CAF alone negatively impact the typical behavioral of zebrafish. When associated, changes in cognition, memory, oxidative and mitochondrial status are more relevant.

Glyphosate- and Fipronil-Based Agrochemicals and Their Mixtures Change Zebrafish Behavior

Environmental contamination caused by the human occupancy and economic activities that generate a wide range of contaminated effluents that reach natural water resources, is a current reality. Residues of agrichemicals used in plant production were detected in different environments and in different countries. Among these agrochemicals, we studied a glyphosate-based herbicide (GBH), a fipronil-based insecticide (FBI), and their mixtures (GBH + FBI). Zebrafish exposed to 3 and 5 mg/L of GBH spend more time in the top zone and less time in the bottom zone. Fish exposed to 0.009 and 0.018 mg/L of FBI spent less time in the bottom zone, whereas zebrafish exposed to the three GBH + FBI mixtures spend more time in the top zone compared with unexposed control fish. This clear anxiolytic pattern, in an environmental context, can directly impair the ability of fish to avoid or evade predators. We concluded that both glyphosate-based herbicide and fipronil-based insecticide and their mixtures alter zebrafish behavior, which may result in significant repercussions on the maintenance of the species as well as on the food chain and the ecosystem.

Previous Treatment with Trilostane and Levotiroxin in Subdosis Difficult the Diagnosis of Canine Hypothyroidism

Background: hypothyroidism is a disease of clinical importance that causes multisystem disorders, which can be confused with other endocrinopathies. Rapid and accurate diagnosis is necessary in order to avoid worsening of the clinical manifestation. The use of drugs in a wrong way can directly imply the difficulty of the diagnostic approach, since they may causechanges in the biochemical profiles, which are of great importance as markers in diseases of animals with low thyroid function.Case: The case reports a German Spitz male, one year old and six months old, neutered, who presented bilateral do not cause itching alopecia, being treated by another professional for endocrine and fungal affections. In this same medical appointment were neglected biochemical and hematological profile exams. The exams that had been performed were skin scrapings,which showed growth of fungi and bacteria, besides the measurement of thyroid hormones as TSH, T4L (T4 free) e T3, and also the low-dose dexamethasone suppression test. Based on the findings the therapy instituted by such professional was the administration of itraconazole (ITL®), levothyroxine sodium (compounded drugs) and trilostane (compounded drugs). With absence of clinical improvement, the guardian came to the hospital veterinary, in search of a second diagnostic opinion, where during the collection of information at the time of the anamnesis the patient presented lethargy, drowsiness and absence of hair on both sides. During the clinical examination, the animal presented mild bradycardia and a slightly diminished rectal temperature; in the dermatological evaluation the presence of pup pelt, cutaneous hyperpigmentation and hair thinning in the abdominal area were noted. From this evaluation, hematological exams were requested, which had altered the presence of lymphocytosis, and biochemical tests, where changes in the cholesterol and triglyceride levels were expected, but they were within the normal range. Hormone measurement showed decreased TSH and T4L levels within the reference range. Thyroid ultrasonography demonstrated a hypoplastic gland, while the assessment of abdominal organs were preserved. Based on this, the new therapy instituted was the increase of levothyroxine sodium (Puran®) dose with the withdrawal of other drugs that were being administered to the patient. Over the course of five months, the tutor returned because of lack of improvement in the condition, where he returned to present symptoms such as drowsiness, apathy and indisposition. Thus, a new battery of tests was requested, where the biochemical and hormonal parameters were within the normal range. Due to TSH being within normal, it was decided to change the medication for another version of human levothyroxine sodium (Synthroid®), which has been presenting satisfactory results so far.Discussion: In cases of patients, even when young, when they present bilateral symmetrical alopecia, complementary exams such as scraping of the skin and hair, trichrome and fungal culture, together with hemogram and biochemical profile, are necessary for discarding of endocrinopathies other than hypothyroidism. Treatments instituted with drugs such as trilostan cause changes in laboratory tests, which may make diagnosis difficult. Treatment with levothyroxine sodium expected in patients with hypothyroidism, and serum TSH and T4L levels should be monitored for evaluation of treatment efficacy. The present study demonstrated that the inadequate treatment made diagnosis difficult due to hematological andbiochemical alterations.Keywords: alopecia, dog, endocrine dermatopathy, hypothyroidism, levothyroxine, trilostane.

Waterborne aripiprazole blunts the stress response in zebrafish

Here we provide, at least to our knowledge, the first evidence that aripiprazole (APPZ) in the water blunts the stress response of exposed fish in a concentration ten times lower than the concentration detected in the environment. Although the mechanism of APPZ in the neuroendocrine axis is not yet determined, our results highlight that the presence of APPZ residues in the environment may interfere with the stress responses in fish. Since an adequate stress response is crucial to restore fish homeostasis after stressors, fish with impaired stress response may have trouble to cope with natural and/or imposed stressors with consequences to their welfare and survival.