Cysticercus fasciolaris infection induced oxidative stress and apoptosis in rat liver: a strategy for host-parasite cross talk

The infection of Cysticercus fasciolaris in natural rats (Rattus species) residing in human residence areas, Nakhon Si Thammarat, Thailand

Cysticercus fasciolaris (C. fasciolaris) is the larval stage of a cestode parasite named Taenia taeniaeformis (T. taeniaeformis). C. fasiolaris is found in small rodents, especially rats. Rattus species are listed as intermediate hosts of this parasite, and cats are the main definitive host of C. fasiolaris. The objective of this study was to study the pathological, microscopic, and molecular aspects of C. fasciolaris in rodents residing in human residence areas. One hundred and two rodents were trapped in human settlements and dissected for larva-containing cyst examinations in the body cavity. The larvae of C. fasciolaris were investigated using histopathological examination, microscopic observations under a stereomicroscope and scanning electron microscope, and molecular detection using polymerase chain reaction. The prevalence of hepatic cysts containing larvae was 8.91% (95% CI = 4.16-16.24). In addition, the older larvae also had longer micropapillae. Histopathological investigation revealed normal hepatic tissue containing larvae and a scanty fluid cyst. The cyst capsule contains mostly mononuclear cells and spindle cells in all infected rats. The molecular detection using two primer sets revealed the amplicons were similar to the clade of C. fasciolaris. In the future, more investigation is necessary to fully understand the parasite's molecular pathogenesis and virulent molecules, which are less obvious.

High Prevalence of Bovine Cardiac Cysticercosis in Upper Egypt: An Epidemiological and Histopathological Study

Bovine cysticercosis is categorized as a serious parasitic zoonotic infestation. The infection is mainly caused by the tapeworm Taenia saginata, which infects cattle and humans. The larval stage, Cysticercus bovis (C. bovis), is found in the skeletal and cardiac muscles of infected cattle. Despite its potential public health concern, few studies have been conducted on cardiac cysticercosis in Upper Egypt. This study investigates the prevalence, epidemiology, and impact of cardiac cysticercosis in Upper Egypt, emphasizing how histopathological changes in cardiac muscle and physiological parameters might be associated with the infection. From December 2022 to October 2023, a total of 941 animals from Assiut province, Upper Egypt, were slaughtered and their cardiac muscles were examined for the presence of C. bovis. Cysts were classified as viable or degenerated through macroscopic inspection. The overall prevalence of C. bovis infected hearts made up 10.8% of the total examined. The highest prevalence rate was in the summer season followed by spring; winter had the lowest infections. The histopathological examination of infected tissues revealed immune cell infiltration around Cysticercus-infected areas. Additionally, Bax immunostaining demonstrated the apoptotic effect of cysticercosis. Regarding the measured physiological parameters, there were non-significant changes in plasma levels of total protein and albumin in cattle infected with cysticercosis compared with control animals. Moreover, there was a significant decrease in total antioxidant capacity (TAC) combined with a significant increase in lipid peroxide (Malondialdehyde) (MDA), troponin T, and lactate dehydrogenase (LDH) activity in infected animals. The present work documented a set of epidemiological and pathological findings, revealing that C. bovis is a potentially harmful parasite and can cause significant health problems in both cattle and humans.

Pfaffia glomerata polyploid accession compromises male fertility and fetal development

ETHNOPHARMACOLOGICAL RELEVANCE

Pfaffia glomerata (Spreng.) Pedersen has traditionally been used as a tonic and a stimulant by the Brazilian population. It shows higher biomass accumulation and production of secondary compounds, such as the phytosterol 20-hydroxyecdysone.

AIMS

The present study aimed to evaluate the effects of the hydroalcoholic extract of the root of tetraploid P. glomerata (BGEt) on testicular parenchyma, and its implications on fertility.

MATERIAL AND METHODS

Adult Swiss mice were divided as: control (water) and sildenafil citrate (7 mg/kg), BGEt at 100, 200, and 400 mg/kg, and BGEtD 200 mg/kg (treated with BGE every three days). Males (n = 4/group) were mated with normal untreated adult females to assess fertility rates, while other animals (n = 6/group) were euthanized for testis, epididymis, and oxidative stress analyses.

RESULTS

Increase in tubule diameter and epithelium height in the discontinuous group, in addition to an increase in the proportion of tubules with moderate pathologies was observed. The pre-implantation loss was lower in all treated groups. The post-implantation loss was significantly increased in all treated groups, except for the lowest BGEt dose. BGEt intake caused a decrease in daily sperm production, along with the number and quality of sperm in the epididymis. Changes were observed in protein carbonylation and hydrogen peroxide and nitric oxide levels, characterizing oxidative stress.

CONCLUSIONS

The hydroalcoholic extract of P. glomerata tetraploid altered sperm and testicular parameters, compromising embryonic development after implantation.

Morphophysiological alterations in fruit-eating bats after oral exposure to deltamethrin

Deltamethrin (DTM) is a synthetic pyrethroid widely used in the cultivation and management of several crops due to its insecticidal action. Application to crops of pyrethroids such as DTM can result in the exposure of water and fruit consumed by fruit bats having a high pyrethroid content which may be harmful. Therefore the objective of this study was to evaluate the effects of short-term oral exposure of the fruit-eating bats (Artibeus lituratus) to two concentrations of DTM (0.02 and 0.04 mg/kg of papaya) on histopathology of the intestine, liver and kidney. The intestine of the animals exposed to both concentrations showed inflammatory infiltrate, degeneration, necrosis and goblet cell hyperplasia as the most frequent pathologies. Besides, the acid mucins showed an increase in the frequency of non-viable cells. The liver showed hepatocyte vacuolizatio and nuclear enlargement, as well as inflammatory infiltrate and steatosis. The kidneys of the exposed animals showed and inflammatory infiltrate, benign nephrosclerosis, vacuolization and necrosis. Also, DTM reduced nitric oxide synthesis, decreased glomerular diameter and increased glycogen percentage in the proximal tubules. Our results suggest that acute exposure to DTM at low concentrations has the potential to induce pronounced histopathological changes in vital organs, such as intestine, liver and kidney of fruit-eating bats.

Short-term intake of deltamethrin-contaminated fruit, even at low concentrations, induces testicular damage in fruit-eating bats (Artibeus lituratus)

Deltamethrin (DTM) is a pyrethroid insecticide widely used for agricultural purposes. Exposure to DTM has proven to be harmful to humans, but whether low, environmental concentrations of this pesticide also poses a threat to wild mammals is still unknown. In Neotropical areas, bats play important roles in contributing to forest regeneration. We investigated the effects of DTM exposure on the reproductive function of male Neotropical fruit-eating bats (Artibeus lituratus), known for contributing to reforestation through seed dispersal in Neotropical Forests. Bats were assigned to 3 groups: control (fed with papaya); DTM2 (fed with papaya treated with DTM at 0.02 mg/kg) and DTM4 (fed with papaya treated with DTM at 0.04 mg/kg) for seven days. Bats from DTM2 and DTM4 groups showed increased testicular levels of nitric oxide and superoxide dismutase and catalase activities. The germinal epithelium from DTM4 bats showed non-viable cells and cell desquamation, indicating microscopic lesions and Leydig cells atrophy. Our results demonstrate the onset of cell degeneration that may affect the reproductive function in DTM exposed bats.

Effect of the topical administration of N-(2-(4-bromophenylamino)-5-(trifluoromethyl)phenyl)nicotinamide compound in a murine subcutaneous melanoma model

Conventional treatments for metastatic melanomas are still ineffective and generate numerous side effects, justifying the search for new therapies. The antimetastatic effect of the named N-(2-(4-bromophenylamino)-5-(trifluoromethyl)phenyl)nicotinamide (SRVIC30) compound has been previously demonstrated in murine melanoma. Herein, we aimed to evaluate its effect when topically administrated in a murine subcutaneous melanoma model. For that, mice C57BL/6 were injected subcutaneously with 2 × 10 B16-F10 cells. Topical treatment began when tumors became visible on animal's back. Therefore, tumor volume was measured three times a week until it reaches 12 mm approximately. At this point, 40 mg oil-in-water cream (Lanette) without (control mice; n = 10) or with SRVIC30 compound (SRVIC30 group; n = 10 animals) were spread daily over the tumor external surface using a small brush for 14 days. The treatments increased the percentage of peroxidase antioxidant enzyme and dead cells via caspase-3 activation, with a consequent deposit of collagen fibers in the tumors. In addition, the skin of treated animals showed the presence of inflammatory infiltrate. Finally, SRVIC30 did not show signs of toxicity. Thus, we concluded that the topic administration of SRVIC30 was able to influence crucial anticancer processes such as tumor cells apoptosis and surrounding microenvironment.

Effects of subchronic exposure to environmentally relevant concentrations of the herbicide atrazine in the Neotropical fish Astyanax altiparanae

Atrazine (ATZ) is among the most widely used herbicides in the world, and yet it has a potential to contaminate aquatic environments due to pesticide leaching from agricultural areas. In the Neotropical region, studies about the effects of this herbicide in native aquatic wildlife is scarce.Our study aimed at investigating the effects of a 30-day exposure to a commercial atrazine formulation on oxidative stress parameters, histopathology in testis and liver, and hormone levels in males and female of yellow-tailed tetra fish (Astyanax altiparanae). Adults were exposed to low but environmentally relevant concentrations of atrazine as follows: 0 (CTL-control), 0.5 (ATZ0.5), 1 (ATZ1), 2 (ATZ2) and 10 (ATZ10) μg/L. Our results showed decreased GST activity in gills in all groups of exposed animals and increased CAT activity in gills from the ATZ10 group. In the liver, there was an increase in lipid peroxidation in fish from ATZ1 and ATZ2 groups. Histological analysis of the liver showed increased percentage of sinusoid capillaries in ATZ2 fish, increased vascular congestion in ATZ1 and increased leukocyte infiltration in the ATZ10 group. Hepatocyte diameter analysis revealed a decrease in cell size in all groups exposed to ATZ, and a decrease in hepatocyte nucleus diameter in ATZ1, ATZ2 and ATZ10 groups. Endocrine parameters did not show significant changes following ATZ exposure, although an increase of triiodothyronine/thyroxine (T₃/T₄) ratio was observed in ATZ2 fish. Our results provide evidence that even low, environmentally relevant concentrations of ATZ produced oxidative damage and histological alterations in adult yellow-tailed tetra.

Hepatic transcriptome study of Taenia asiatica infection in suckling pigs

Taenia asiatica is a crucial Taenia that is prevalent in East and Southeast Asia. Domestic pigs and wild boars are essential intermediate hosts for Taenia. Cysticercus larvae are mainly parasitic in the liver of domestic pigs. The Taenia asiatica was collected from Liangmu Township, Duyun City, Guizhou Province. Twelve Yorkshire Suckling pigs of 20 days of age were randomly divided into an experimental and control group of 6 pigs each. RNA sequencing (RNA-seq) technology was used to detect the expression differences of the mRNA transcriptomes in the liver of the experimental and control group at different infection times. Differential genes were analyzed by bioinformatics and verified by Real Time-PCR(RT-PCR). On the 15th and 75th days after infection, 152 and 558 differentially expressed genes were detected in the liver of the experimental group, respectively, accounting for 0.85% and 3.12% of all identified transcribed RNA genes, respectively. Through GO and KEGG related bioinformatics analysis, it was found that these differentially expressed genes are involved in the immune response, material metabolism, fibrosis, and tissue proliferation and repair of suckling pig liver, and related to MHC antigen processing and presentation, cytochrome P450, transforming growth factor-beta (TGF-β) signaling pathway and so on. Cysticercus asiatica parasites cause significant differential gene expression in the liver of suckling pigs. Specific differentially expressed genes are involved in biological processes such as liver metabolism, immune response, and tissue repair or regeneration in suckling pigs. The immune evasion is related to the immuno-suppressive response of the intermediate host.

Euterpe oleracea (Martius) Oil Reverses Testicular Alterations Caused after Cadmium Administration

Cadmium (Cd) is an environmental pollutant that induces reproductive toxicity by generating reactive oxygen species, which leads to oxidative stress. Euterpe oleracea fruits are known for being rich in oils containing triacylglycerol and phenolic compounds. They are considered as potent antioxidants to be used to counteract Cd effects within the testis. In the present study, adult males Swiss mice were treated with CdCl₂ aqueous solution (4.28 mg/kg) by gavage for 7 days. The experimental groups were treated with Euterpe oleracea oil at the doses of 50, 100, and 150 mg/kg, for 42 days. The results showed that Cd intoxication led to increased tubular pathologies, such as reduction in epithelium height and area thus increasing both luminal diameter and tubule-epithelium ratio. Besides, Leydig cell's morphometry indicated reduction in nucleus and cytoplasm volumes of this cell type, which were recovered after E. oleracea oil intake. In addition, serum testosterone levels, testicular Mn and Zn concentrations, SOD and CAT activity, and germ cell viability increased after oil intake. Therefore, E. oleracea oil showed a regenerative effect in the testicular parenchyma negatively affected by Cd, mainly in the animals that received the highest oil concentration (150 mg/kg).

Giardia duodenalis Induces Apoptosis in Intestinal Epithelial Cells via Reactive Oxygen Species-Mediated Mitochondrial Pathway In Vitro

The intestinal protozoan parasite, Giardia duodenalis, infects a large number of people in the world annually. Giardia infection has been considered a negative effect on intestinal epithelial cell growth, while the underlying mechanisms remain to be explored. Here we evaluated reactive oxygen species (ROS) production and apoptotic events in Giardia trophozoites-stimulated Caco-2 cells via fluorescence microscopy, transmission electron microscopy, flow cytometry, western blot, and cell counting kit-8 analyses. The results showed that Giardia trophozoite treatment could induce lactate dehydrogenase release and Caco-2 cell apoptosis. The ROS levels were increased post treatment. The observed typical characteristics of mitochondria damage include significant swelling and degeneration of matrix and cristae. After trophozoite treatment, the level of Bax protein expression was increased, while Bcl-2 protein decreased. Trophozoite stimulation also led to reduction of mitochondrial membrane potential and release of cytochrome c from the mitochondria to the cytoplasm, and this process was accompanied by activation of caspase-9 and caspase-3 and poly (ADP-ribose) polymerase 1 cleavage. Pretreatment with N-acetyl-L-cysteine, a ROS inhibitor, reversed G. duodenalis-induced Caco-2 cell apoptosis. Taken together, we indicated that G. duodenalis could induce Caco-2 cell apoptosis through a ROS- and mitochondria-mediated caspase-dependent pathway. This study furthers our understanding of the cellular mechanism of the interaction between Giardia trophozoites and host cells.

How bad is brazilian ginseng extract for reproductive parameters in mice?

Properties attributed to the Panax ginseng are also attributed to the Brazilian ginseng, such as adaptogenic and aphrodisiac effects. There are studies demonstrating that the Brazilian ginseng (BGE) possibly increases the serum levels of testosterone and nitric oxide in mice and rats. The present study aimed to evaluate the effects of its extract on male fertility and sperm quality. Male Swiss mice (n = 60) were divided into six groups. The control animals were provided 0.5 mL of water, and 0.5 mL of water containing 7 mg/kg per day (d) sildenafil citrate. Other animals were treated with BGE at 100 mg/kg/d, 200 mg/kg/d, and 400 mg/kg/d by gavage for 42 days. Finally, animals from the last group received 200 mg/kg BGE every 3 days (3-3d) by gavage for 42 days. The results showed a reduction in the number of resistant spermatids in the testis and damage to daily sperm production, culminating in a reduction in the number of epididymal spermatozoa. Although the sperm quality decreased in all experimental animals, only males treated with BGE 100 mg/kg/d showed pre and post implantation embryo losses. We concluded that BGE alters sperm viability compromising the embryonic development after implantation.

Molecular and Functional Characterization of Inhibitor of Apoptosis Proteins (IAP, BIRP) in Echinococcus granulosus

The larval stage of Echinococcus granulosus sensu lato, resulting in cystic echinococcosis, a parasitic zoonosis, causes huge economic losses to the livestock industry and poses a threat to public health. Inhibitor of apoptosis proteins (IAPs) is a class of endogenous anti-apoptotic family, which plays a significant functional role in the regulation of organism’s development. Herein, to explore potential functions of IAPs in E. granulosus, two members of IAPs from E. granulosus (Eg-IAP and Eg-BIRP) were cloned, expressed, and molecularly characterized. Eg-IAP and Eg-BIRP encoded putative 331 and 168 residue proteins, respectively. Bioinformatic analysis showed that both proteins contained a type II BIR domain-the essential functional domain of IAPs. Fluorescence immunohistochemistry revealed that both proteins were ubiquitously localized in all life-cycle stages of E. granulosus. Our fluorescent quantitative PCR (RT-qPCR) results revealed relatively higher transcription levels of two Eg-IAPs in protoscoleces (PSCs) compared to the 18-day strobilated worms. We further used different concentrations of LCL161, a Smac-mimetic pan-IAPs inhibitor, to induce the apoptosis in PSCs in vitro, and revealed that the survival rate of PSCs and transcription levels of both genes were negatively correlated with the concentration of LCL161. While the results of light microscopy, transmission electron microscopy (TEM), and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay also showed a higher apoptotic rate in PSCs with the increasing concentrations of LCL161. Taken together, our findings provide the reasonable evidence that both Eg-IAP and Eg-BIRP have potential implication in critical anti-apoptotic roles during the development of E. granulosus.

Cadmium-Induced Testicular Toxicity in Mice: Subacute and Subchronic Route-Dependent Effects

This study aimed to compare Cd exposure by intraperitoneal (i.p.) and oral routes, evaluating the testicular subacute and subchronic effects. Adult male mice were separated into three groups subdivided according to the experimental period (7 and 42 days after Cd exposure: subacute and subchronic effects, respectively): one group received water and two groups received CdCl₂ (1.2 mg/kg i.p. and 24 mg/kg oral). The testicular concentration of essential minerals and Cd, activity of antioxidant enzymes and markers of oxidative stress, histology, and testicular histomorphometry were evaluated. The subacute effect of oral Cd showed reduced Fe concentration, while Ca and Cu increased in this route. The subchronic effect promoted decreasing in Mg in i.p. and oral routes, whereas Zn decreased only in the oral, and the Fe concentration did not change. SOD activity decreased in the oral subacute evaluation and in both pathways, i.p. and oral routes, in the subchronic evaluation, while GST activity increased, and MDA concentration decreased. Labeling of apoptotic cells was increased in the subacute and subchronic evaluation. Seminiferous epithelium degeneration, death of germ cells, and Leydig cell damages occurred in i.p. and oral routes. However, these damages were more intense in the oral route, mainly evaluating the subchronic effects. The results confirm that the severity of Cd-induced testicular injury depends on the pathway, as well as the duration of exposure.

Subacute Testicular Toxicity to Cadmium Exposure Intraperitoneally and Orally

The toxic effects of cadmium (Cd) on reproductive parameters are widely described in the literature. Experimental models often make use of the intraperitoneal route (i.p.), although human intoxication occurs preferentially by the oral route and can be continuous. However, little is known about the effect of Cd administration routes on the testicular structure. Thus, this study investigated the testicular impact of Cd exposure comparing both i.p. and oral routes, both single dose (SD), in addition to the oral route in fractional doses (FD). Swiss adult male mice received CdCl₂ 1.5 mg/kg i.p., 30 mg/kg oral SD, and 4.28 mg/kg oral FD for 7 consecutive days. The Cd bioaccumulation was observed in all routes, mainly in the oral FD route. The concentrations of testicular Ca and Cu decreased in all animals exposed to Cd, while Zn and Mn decreased only in the i.p. route. Testicular SOD activity was reduced in both routes of oral administration, while CAT increased in the i.p. route, and GST increased in all animals exposed to Cd. Changes in the tubular parameters and cell viability were observed in both routes of Cd administration but were more intense in the oral route, mainly in the FD. Serum testosterone concentration was reduced in both routes of oral administration. Tubular damage, such as the vacuolization of the seminiferous epithelium, germ cell detachment, and seminiferous tubule degeneration, occurred in all groups exposed to Cd. Therefore, the oral Cd administration presented greater potential to promote testicular damage, mainly when the metal was given in a fractionated way.

The liver proteome in a mouse model for Ascaris suum resistance and susceptibility: evidence for an altered innate immune response

Background

Ascariasis is a neglected tropical disease that affects 800 million people worldwide. Whereas most people only experience light worm burden, some people experience heavy worm burdens even after several rounds of chemotherapy, a phenomenon known as predisposition. Such heavy infections are associated with more severe symptoms and increased chronic morbidity.

Methods

In order to investigate potential mechanisms that may explain the observed predisposition, we infected mice with the porcine ascarid Ascaris suum using an established mouse model with two different mouse strains, where the C57BL/6J strain is more susceptible to infection and therefore a model for heavy infection and the CBA/Ca strain is more resistant and thus a model for light infection. At day 7 post-infection we investigated the liver proteome, using shotgun mass spectrometry, of both infected and control mice of each strain.

Results

We identified intrinsic differences, between the two mouse strains, in both oxidative phosphorylation proteins and proteins involved in retinol metabolism. Additionally, we found differences between the two mouse strains in activation of the complement system, where the CBA/Ca strain has higher protein abundances for lectin pathway proteins and the C57BL/6J strain has higher protein abundances for complement inhibiting proteins. The CBA/Ca strain had a higher abundance of proteins involved in the activation of the complement cascade via the lectin pathway. In contrast, the C57BL/6J strain demonstrated a higher abundance of proteins involved in arresting the complement pathway.

Conclusions

We observed clear differences between the two mouse strains both intrinsically and under infection.

Electronic supplementary material

The online version of this article (10.1186/s13071-019-3655-9) contains supplementary material, which is available to authorized users.

Anisakis pegreffii impacts differentiation and function of human dendritic cells

Human dendritic cells (DCs) show remarkable phenotypic changes when matured in the presence of helminth-derived products. These modifications frequently elicited a polarization towards Th2 cells and regulatory T cells thus contributing to immunological tolerance against these pathogens. In this study, the interaction between DCs and larvae of the zoonotic anisakid nematode Anisakis pegreffii was investigated. A. pegreffii larvae were collected from fish hosts, and monocyte-derived DCs were cocultured in the presence of the live larvae (L) or its crude extracts (CE). In both experimental conditions, A. pegreffii impacted DC viability, hampered DC maturation by reducing the expression of molecules involved in antigen presentation and migration (ie HLA-DR, CD86, CD83 and CCR7), increased the phagosomal radical oxygen species (ROS) levels and modulated the phosphorylation of ERK1,2 pathway. These biological changes were accompanied by the impairment of DCs to activate a T-cell-mediated IFNγ. Interestingly, live larvae appeared to differently modulate DC secretion of cytokines and chemokines as compared to CE. These results demonstrate, for the first time, the immunomodulatory role of A. pegreffii on DCs biology and functions. In addition, they suggest a dynamic contribution of DCs to the induction and maintenance of the inflammatory response against A. pegreffii.

Hydroalcoholic extract of Pfaffia glomerata alters the organization of the seminiferous tubules by modulating the oxidative state and the microstructural reorganization of the mice testes

ETHNOPHARMACOLOGICAL USAGES

Leaves and roots of Pfaffia glomerata areused as aphrodisiacs, tranquilizers and antirheumatics. Due to the lack of experimental scientific data, studies are necessary to identify its medicinal properties.

AIMS

The present study aimed to evaluate the effect of hydroalcoholic root extract of P. glomerata (Brazilian ginseng extract - BGE) on testicular parenchyma, and evaluate possible harmful effects through testicular oxidative stress analysis.

MATERIALS AND METHODS

Adult mice were divided into 6 groups: control (water), sildenafil citrate, BGE (100, 200 and 400 mg/kg/day), and BGE (200 mg/kg every three days).

RESULTS

The treatment reduced the volumetric proportions of seminiferous tubules and epithelium, the number of Sertoli cells, and increased hydrogen peroxide levels, without affecting sperm production. It also caused cell death and changes in the frequency of stages of the seminiferous epithelium cycles. The 100 mg/kg dose responds in a similar way to sildenafil citrate, promoting changes in the gonadal structure, but with efficient response to contain the damage.

CONCLUSIONS

Doses of 200 mg/kg, continuous or discontinuous, induced an increase in testicular nitric oxide, as well as sildenafil citrate, showing be efficient as aphrodisiac, but promotes cell death regardless of the form of administration.

Fertility in male rats: Disentangling adverse effects of arsenic compounds

Arsenic impairs male reproductive functions. However, it is not clear whether different arsenic compounds similarly affect fertility. In this study, we compared the impact of sodium arsenite and arsenate on sperm quality and fertility. After 56 d exposure, male Wistar rats were mated and pregnant females were evaluated by fertility indexes. Clearly, exposure to 10 mg/L arsenite reduced daily sperm production via H₂O₂ overproduction and germ cells loss. Animals from this group also showed a decrease in epididymal sperm counts and percentage of sperm with intact membranes. Moreover, they presented low fertility potential and high preimplantation loss. In contrast, 10 mg/L arsenate caused oxidative stress in testis, mineral imbalance in epididymis, and sperm membranes damage, with no effects on fertility. Both arsenic compounds at 0.01 mg/L altered reproductive parameters. We concluded that arsenite is more harmful than arsenate to sperm quality and male fertility, with negative influences in early pregnancy.

Telomere length and antioxidant defense associate with parasite-induced retarded growth in wild brown trout

Early growth conditions can have profound impacts on individuals' development, growth and physiology, with subsequent long-term consequences for individuals' fitness and life expectancy. Telomere length (TL) has been suggested to indicate both individual fitness and life expectancy in wide range of species, as the telomere attrition rate at early age can be accelerated due to exposure to various stressors, including parasites and inflammatory diseases, which increase production of reactive oxygen species (ROS) and influence antioxidant (AO) levels. We investigated impacts of Tetracapsuloides bryosalmonae infection, a causative agent of proliferative kidney disease (PKD), on AO status and TL in a natural population of juvenile brown trout (Salmo trutta). The fish with higher parasite load showed more severe kidney hyperplasia, anemia and smaller body size compared to less parasitized fish. Furthermore, fish with severe PKD symptoms had lower SOD-, CAT- and GST activity than fish with milder kidney hyperplasia. However, parasite load was not directly correlated either with AOs or with TL. Smaller fish showed shorter TLs, potentially reflecting lower individual quality. The fish, which were less sensitive to parasite-induced impaired growth, quantified as parasite load-adjusted fork length, showed also longer TLs, lower GR- and GST activity and less GSH_tot compared to more sensitive fish. These results provide novel knowledge about the impacts of the PKD in brown trout at the molecular level and support the idea that TL may reflect individual quality and ability to cope with parasitic infections.

Grasslands: A Source of Secondary Metabolites for Livestock Health

The need for environmentally friendly practices in animal husbandry, in conjunction with the reduction of the use of synthetic chemicals, leads us to reconsider our agricultural production systems. In that context, grassland secondary metabolites (GSMs) could offer an alternative way to support to livestock health. In fact, grasslands, especially those with high dicotyledonous plant species, present a large, pharmacologically active reservoir of secondary metabolites (e.g., phenolic compounds, alkaloids, saponins, terpenoids, carotenoids, and quinones). These molecules have activities that could improve or deteriorate health and production. This Review presents the main families of GSMs and uses examples to describe their known impact on animal health in husbandry. Techniques involved for their study are also described. A particular focus is put on anti-oxidant activities of GSMs. In fact, numerous husbandry pathologies, such as inflammation, are linked to oxidative stress and can be managed by a diet rich in anti-oxidants. The different approaches and techniques used to evaluate grassland quality for livestock health highlight the lack of efficient and reliable technics to study the activities of this complex phytococktail. Better knowledge and management of this animal health resource constitute a new multidisciplinary research field and a challenge to maintain and valorize grasslands.