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Tilapiine fishes of the genus Oreochromis vary in their euryhaline capabilities, therefore inhabiting aquatic environments of different salinities across the African continent. We analyzed the differential gene expression in the gills before and after 6 weeks salinity challenge between the highly tolerant Mozambique tilapia (Oreochromis mossambicus) and the less tolerant Nile tilapia (O. niloticus). The pathways triggered by salinity in both tilapia species reveal immune and cell stress responses as well as turnover of ionocytes. Nevertheless, the actual differential expressed genes vary between these two species, pointing at differential transcriptomic architecture, which likely contribute to the species osmoregulation capabilities in elevated salinities.

A simple and intuitive formula for the estimation of urine osmolality (Uosm) using the measured concentrations of major active urine osmolytes over a wide range of urine dilutions was proposed in healthy cats. Sixty-three urine samples were retrieved using ultrasound-guided cystocentesis from sixteen healthy cats under 5 years of age receiving intravenous infusion over a period of 24 h. Samples were collected at baseline (T0), T2, T6, T12, and T24. Urine osmolality was measured using a freezing-point osmometer, and the concentrations of osmolytes (urea, sodium, glucose, and potassium) were evaluated. A simple linear regression model for a clinical use was selected, and the agreement between the calculated and actual urine osmolalities was assessed. Urinary concentrations of urea, sodium and glucose were the three variables included in the model with the lowest AICC. Urine osmolality can be predicted accurately and precisely using urine urea, sodium and glucose with the following equation: Uosm = 1.25 × urea (mmol/l) or 20.87 × urea (g/l) + 1.1 × sodium (mmol/l) + 67 × glucose (mmol/l) or 3.72 × glucose (mg/dl). The concordance correlation coefficient for repeated measures between the actual and the calculated urine osmolality was extremely close to 1, which supported a high agreement: 0.996 (CI 95%: [0.993; 0.998]). In a population of healthy cats, urine osmolality can be predicted accurately and precisely using urinary urea, sodium and glucose concentrations. Similar formulae could potentially be established to help the clinician in pathological situations.

Spatio-temporally heterogeneous environments may lead to unexpected population dynamics. Knowledge is needed on local properties favouring population resilience at large scale. For pathogen vectors, such as tsetse flies transmitting human and animal African trypanosomosis, this is crucial to target management strategies. We developed a mechanistic spatio-temporal model of the age-structured population dynamics of tsetse flies, parametrized with field and laboratory data. It accounts for density- and temperature-dependence. The studied environment is heterogeneous, fragmented and dispersal is suitability-driven. We confirmed that temperature and adult mortality have a strong impact on tsetse populations. When homogeneously increasing adult mortality, control was less effective and induced faster population recovery in the coldest and temperature-stable locations, creating refuges. To optimally select locations to control, we assessed the potential impact of treating them and their contribution to the whole population. This heterogeneous control induced a similar population decrease, with more dispersed individuals. Control efficacy was no longer related to temperature. Dispersal was responsible for refuges at the interface between controlled and uncontrolled zones, where resurgence after control was very high. The early identification of refuges, which could jeopardize control efforts, is crucial. We recommend baseline data collection to characterize the ecosystem before implementing any measures.

Many animals have evolved associations with symbiotic microbes that benefit the host through increased growth, lifespan, and survival. Some interactions are obligate (essential for survival) while others are facultative (usually beneficial but not essential). Not all individuals host all facultative symbionts in a population, and thus there is probably a trade-off between the cost of hosting these symbionts and the benefits they confer to the host. Plant-sucking insects have been one of the most important models to test these costs and benefits experimentally. This research is now moving beyond the description of symbiont effects towards understanding the mechanisms of action, and their role in the wider ecological community. We present a quantitative and systematic analysis of the published evidence exploring this question. We found that whitefly and true bugs experience benefits through increased growth and fecundity, whereas aphids experience costs to their fecundity but benefits through increased resistance to natural enemies. We also report the lack of data in some plant-sucking groups, and explore variation in effect strengths and directions across aphid host, symbiont and plant species thus highlighting the importance of considering the context dependency of these interactions.

The process of local adaptation involves differential changes in fitness over time across different environments. Although experimental evolution studies have extensively tested for patterns of local adaptation at a single time point, there is relatively little research that examines fitness more than once during the time course of adaptation. We allowed replicate populations of the fruit pest Drosophila suzukii to evolve in one of eight different fruit media. After five generations, populations with the highest initial levels of maladaptation had mostly gone extinct, whereas experimental populations evolving on cherry, strawberry and cranberry media had survived. We measured the fitness of each surviving population in each of the three fruit media after five and after 26 generations of evolution. After five generations, adaptation to each medium was associated with increased fitness in the two other media. This was also true after 26 generations, except when populations that evolved on cranberry medium developed on cherry medium. These results suggest that, in the theoretical framework of a fitness landscape, the fitness optima of cherry and cranberry media are the furthest apart. Our results show that studying how fitness changes across several environments and across multiple generations provides insights into the dynamics of local adaptation that would not be evident if fitness were analysed at a single point in time. By allowing a qualitative mapping of an experimental fitness landscape, our approach will improve our understanding of the ecological factors that drive the evolution of local adaptation in D. suzukii.

Spatio-temporally heterogeneous environments may lead to unexpected population dynamics. Knowledge is needed on local properties favouring population resilience at large scale. For pathogen vectors, such as tsetse flies transmitting human and animal African trypanosomosis, this is crucial to target management strategies. We developed a mechanistic spatio-temporal model of the age-structured population dynamics of tsetse flies, parametrized with field and laboratory data. It accounts for density- and temperature-dependence. The studied environment is heterogeneous, fragmented and dispersal is suitability-driven. We confirmed that temperature and adult mortality have a strong impact on tsetse populations. When homogeneously increasing adult mortality, control was less effective and induced faster population recovery in the coldest and temperature-stable locations, creating refuges. To optimally select locations to control, we assessed the potential impact of treating them and their contribution to the whole population. This heterogeneous control induced a similar population decrease, with more dispersed individuals. Control efficacy was no longer related to temperature. Dispersal was responsible for refuges at the interface between controlled and uncontrolled zones, where resurgence after control was very high. The early identification of refuges, which could jeopardize control efforts, is crucial. We recommend baseline data collection to characterize the ecosystem before implementing any measures.

Many animals have evolved associations with symbiotic microbes that benefit the host through increased growth, lifespan, and survival. Some interactions are obligate (essential for survival) while others are facultative (usually beneficial but not essential). Not all individuals host all facultative symbionts in a population, and thus there is probably a trade-off between the cost of hosting these symbionts and the benefits they confer to the host. Plant-sucking insects have been one of the most important models to test these costs and benefits experimentally. This research is now moving beyond the description of symbiont effects towards understanding the mechanisms of action, and their role in the wider ecological community. We present a quantitative and systematic analysis of the published evidence exploring this question. We found that whitefly and true bugs experience benefits through increased growth and fecundity, whereas aphids experience costs to their fecundity but benefits through increased resistance to natural enemies. We also report the lack of data in some plant-sucking groups, and explore variation in effect strengths and directions across aphid host, symbiont and plant species thus highlighting the importance of considering the context dependency of these interactions.

The process of local adaptation involves differential changes in fitness over time across different environments. Although experimental evolution studies have extensively tested for patterns of local adaptation at a single time point, there is relatively little research that examines fitness more than once during the time course of adaptation. We allowed replicate populations of the fruit pest Drosophila suzukii to evolve in one of eight different fruit media. After five generations, populations with the highest initial levels of maladaptation had mostly gone extinct, whereas experimental populations evolving on cherry, strawberry and cranberry media had survived. We measured the fitness of each surviving population in each of the three fruit media after five and after 26 generations of evolution. After five generations, adaptation to each medium was associated with increased fitness in the two other media. This was also true after 26 generations, except when populations that evolved on cranberry medium developed on cherry medium. These results suggest that, in the theoretical framework of a fitness landscape, the fitness optima of cherry and cranberry media are the furthest apart. Our results show that studying how fitness changes across several environments and across multiple generations provides insights into the dynamics of local adaptation that would not be evident if fitness were analysed at a single point in time. By allowing a qualitative mapping of an experimental fitness landscape, our approach will improve our understanding of the ecological factors that drive the evolution of local adaptation in D. suzukii.

Milk contains extracellular vesicles that are released by udder cells and are recognized as a new mechanism for transmitting information from mother to newborn. In this study, extracellular vesicles were isolated from milk of C. dromedarius, C. bactrianus and hybrids from Kazakhstan using optimized density gradient ultracentrifugation. Vesicles were visualized using transmission electron microscopy and characterized using nanoparticle tracking analysis. The purified extracellular vesicles had a heterogeneous size distribution ranging from 25 to 170 nm in diameter with an average yield of 9.5*108 – 4.2*1010 particles per milliliter of milk. Combining classical and advanced proteomic approaches, a comprehensive proteomic analysis of camel milk vesicles was carried out. One thousand ten (1010) unique proteins have been identified that are involved in various biological processes, including most markers associated with small vesicles. As a result, the extracellular vesicles of camel milk are enriched with exosomal proteins. The most common biological processes have been associated with the synthesis and secretion of exosomes. They are mainly involved in molecular functions such as poly RNA and ATP binding, protein binding and structural constituent of the ribosomes.

Our previous article demonstrated that ar-turmerone ((6S)-2-methyl-6-(4-methylphenyl)-2-hepten-4-one) extracted from Curcuma longa L. has a significant larvicidal activity against the fourth instar larvae of Culex pipiens pallens. To reveal the effects of ar-turmerone on C. pipiens pallens larvae, light microscopy and transmission electron microscopy were used to observe the histological and ultrastructure changes in muscle and digestive tissues of fourth instar larvae. It was also revealed by detecting the activity of the acetylcholinesterase (AChE) enzyme and three detoxifying enzymes, including carboxylesterase (CarE), glutathione-S-transferase (GST) and Cytochrome P450 monooxidases (P450). The observation under the light microscope showed that the larvae displayed a disruption of myofibril in ventral muscle cells, the disappearance of nucleolus in the malpighian tubule cells, and the exfoliation of the brush border in midgut epithelial cells, 24 h after treatment. The observation under the transmission electron microscope displayed disorganized Z-lines in the ventral muscle cells, and dissolved membrane of mitochondria, nuclear and endoplasmic reticulum in abdominal cells. The enzymatic activity results showed that ar-turmerone significantly increased the level of detoxifying enzymes, while the activity of AChE was not obviously affected. All the results suggest that the larvicidal mechanism of ar-turmerone is estimated to be stomach poison and the active sites might be the muscle and digestive tissues, and the mode of action of ar-turmerone may be unrelated to AChE.

A study was conducted to investigate the seroprevalence and associated risk factors of Rift Valley fever (RVF) infection in cattle and some selected wildlife species at selected interface areas at the periphery of the Great Limpopo Transfrontier Conservation Area in Zimbabwe. Three study sites were selected based on the type of livestock–wildlife interface: porous livestock–wildlife interface (unrestricted); non-porous livestock–wildlife interface (restricted by fencing) and livestock–wildlife non-interface (totally absent contact or control). Sera were collected from cattle aged ≥ 2 years representing both female and intact male. Sera were also collected from selected wild ungulates from Mabalauta (porous interface) and Chipinda Pools (non-interface) areas of the Gonarezhou National Park. Sera were tested for antibodies to Rift Valley fever virus (RVFV) using a competitive enzyme-linked immunosorbent assay (ELISA) test. AX2 test was used to assess differences between categories, and p < 0.05 was considered as significant. In cattle, the overall seroprevalence was 1.7% (17/1011) (95% confidence interval [CI]: 1.01–2.7). The porous interface recorded a seroprevalence of 2.3% (95% CI: 1.2–4.3), the non-porous interface recorded a prevalence of 1.8% (95% CI: 0.7–4.3) and the non-interface area recorded a seroprevalence of 0.4% (955 CI: 0.02–2.5), but the difference in seroprevalence according to site was not significant (p > 0.05). All impala and kudu samples tested negative. The overall seroprevalence in buffaloes was 11.7% (95% CI: 6.6–19.5), and there was no significant (p = 0.38) difference between the sites (Mabalauta, 4.4% [95% CI: 0.2–24] vs. Chipinda, 13.6% [95% CI: 7.6–23]). The overall seroprevalence in buffaloes (11.7%, 13/111) was significantly (p < 0.0001) higher than in cattle (1.7%, 17/1011). The results established the presence of RVFV in cattle and selected wildlife and that sylvatic infections may be present in buffalo populations. Further studies are

The sugarcane aphid (SCA), Melanaphis Sacchari (Zehntner) (Hemiptera: Aphididae), has been considered an invasive pest of sugarcane in the continental United States since 1977. Then, in 2013, SCA abruptly became a serious pest of U.S. sorghum and is now a sorghum pest in 22 states across the continental United States. Changes in insect-associated microbial community composition are known to influence host-plant range in aphids. In this study, we assessed whether changes in microbiota composition may explain the SCA outbreak in U.S. sorghum. We characterized the SCA bacterial microbiota on sugarcane and grain sorghum in four U.S. states, using a metabarcoding approach. In addition, we used taxon-specific polymerase chain reaction (PCR) primers to screen for bacteria commonly reported in aphid species. As anticipated, all SCA harbored the primary aphid endosymbiont Buchnera aphidicola, an obligate mutualistic bacterial symbiont. Interestingly, none of the secondary symbionts, facultative bacteria typically associated with aphids (e.g., Arsenophonus, Hamiltonella, Regiella) were present in either the metabarcoding data or PCR screens (with the exception of Rickettsiella and Serratia, which were detected by metabarcoding at low abundances <1%). However, our metabarcoding detected bacteria not previously identified in aphids (Arcobacter, Bifidobacterium, Citrobacter). Lastly, we found microbial host-associated differentiation in aphids that seems to correspond to genetically distinct aphid lineages that prefer to feed on grain sorghum (MLL-F) versus sugarcane (MLL-D).

Ticks transmit a wide variety of pathogens including bacteria, parasites and viruses. Over the last decade, numerous novel viruses have been described in arthropods, including ticks, and their characterization has provided new insights into RNA virus diversity and evolution. However, little is known about their ability to infect vertebrates. As very few studies have described the diversity of viruses present in ticks from the Caribbean, we implemented an RNA-sequencing approach on Amblyomma variegatum and Rhipicephalus microplus ticks collected from cattle in Guadeloupe and Martinique. Among the viral communities infecting Caribbean ticks, we selected four viruses belonging to the Chuviridae, Phenuiviridae and Flaviviridae families for further characterization and designing antibody screening tests. While viral prevalence in individual tick samples revealed high infection rates, suggesting a high level of exposure of Caribbean cattle to these viruses, no seropositive animals were detected. These results suggest that the Chuviridae- and Phenuiviridae-related viruses identified in the present study are more likely tick endosymbionts, raising the question of the epidemiological significance of their occurrence in ticks, especially regarding their possible impact on tick biology and vector capacity. The characterization of these viruses might open the door to new ways of preventing and controlling tick-borne diseases.

Milk contains extracellular vesicles that are released by udder cells and are recognized as a new mechanism for transmitting information from mother to newborn. In this study, extracellular vesicles were isolated from milk of C. dromedarius, C. bactrianus and hybrids from Kazakhstan using optimized density gradient ultracentrifugation. Vesicles were visualized using transmission electron microscopy and characterized using nanoparticle tracking analysis. The purified extracellular vesicles had a heterogeneous size distribution ranging from 25 to 170 nm in diameter with an average yield of 9.5*108 – 4.2*1010 particles per milliliter of milk. Combining classical and advanced proteomic approaches, a comprehensive proteomic analysis of camel milk vesicles was carried out. One thousand ten (1010) unique proteins have been identified that are involved in various biological processes, including most markers associated with small vesicles. As a result, the extracellular vesicles of camel milk are enriched with exosomal proteins. The most common biological processes have been associated with the synthesis and secretion of exosomes. They are mainly involved in molecular functions such as poly RNA and ATP binding, protein binding and structural constituent of the ribosomes.

Our previous article demonstrated that ar-turmerone ((6S)-2-methyl-6-(4-methylphenyl)-2-hepten-4-one) extracted from Curcuma longa L. has a significant larvicidal activity against the fourth instar larvae of Culex pipiens pallens. To reveal the effects of ar-turmerone on C. pipiens pallens larvae, light microscopy and transmission electron microscopy were used to observe the histological and ultrastructure changes in muscle and digestive tissues of fourth instar larvae. It was also revealed by detecting the activity of the acetylcholinesterase (AChE) enzyme and three detoxifying enzymes, including carboxylesterase (CarE), glutathione-S-transferase (GST) and Cytochrome P450 monooxidases (P450). The observation under the light microscope showed that the larvae displayed a disruption of myofibril in ventral muscle cells, the disappearance of nucleolus in the malpighian tubule cells, and the exfoliation of the brush border in midgut epithelial cells, 24 h after treatment. The observation under the transmission electron microscope displayed disorganized Z-lines in the ventral muscle cells, and dissolved membrane of mitochondria, nuclear and endoplasmic reticulum in abdominal cells. The enzymatic activity results showed that ar-turmerone significantly increased the level of detoxifying enzymes, while the activity of AChE was not obviously affected. All the results suggest that the larvicidal mechanism of ar-turmerone is estimated to be stomach poison and the active sites might be the muscle and digestive tissues, and the mode of action of ar-turmerone may be unrelated to AChE.

A study was conducted to investigate the seroprevalence and associated risk factors of Rift Valley fever (RVF) infection in cattle and some selected wildlife species at selected interface areas at the periphery of the Great Limpopo Transfrontier Conservation Area in Zimbabwe. Three study sites were selected based on the type of livestock–wildlife interface: porous livestock–wildlife interface (unrestricted); non-porous livestock–wildlife interface (restricted by fencing) and livestock–wildlife non-interface (totally absent contact or control). Sera were collected from cattle aged ≥ 2 years representing both female and intact male. Sera were also collected from selected wild ungulates from Mabalauta (porous interface) and Chipinda Pools (non-interface) areas of the Gonarezhou National Park. Sera were tested for antibodies to Rift Valley fever virus (RVFV) using a competitive enzyme-linked immunosorbent assay (ELISA) test. AX2 test was used to assess differences between categories, and p < 0.05 was considered as significant. In cattle, the overall seroprevalence was 1.7% (17/1011) (95% confidence interval [CI]: 1.01–2.7). The porous interface recorded a seroprevalence of 2.3% (95% CI: 1.2–4.3), the non-porous interface recorded a prevalence of 1.8% (95% CI: 0.7–4.3) and the non-interface area recorded a seroprevalence of 0.4% (955 CI: 0.02–2.5), but the difference in seroprevalence according to site was not significant (p > 0.05). All impala and kudu samples tested negative. The overall seroprevalence in buffaloes was 11.7% (95% CI: 6.6–19.5), and there was no significant (p = 0.38) difference between the sites (Mabalauta, 4.4% [95% CI: 0.2–24] vs. Chipinda, 13.6% [95% CI: 7.6–23]). The overall seroprevalence in buffaloes (11.7%, 13/111) was significantly (p < 0.0001) higher than in cattle (1.7%, 17/1011). The results established the presence of RVFV in cattle and selected wildlife and that sylvatic infections may be present in buffalo populations. Further studies are

The sugarcane aphid (SCA), Melanaphis Sacchari (Zehntner) (Hemiptera: Aphididae), has been considered an invasive pest of sugarcane in the continental United States since 1977. Then, in 2013, SCA abruptly became a serious pest of U.S. sorghum and is now a sorghum pest in 22 states across the continental United States. Changes in insect-associated microbial community composition are known to influence host-plant range in aphids. In this study, we assessed whether changes in microbiota composition may explain the SCA outbreak in U.S. sorghum. We characterized the SCA bacterial microbiota on sugarcane and grain sorghum in four U.S. states, using a metabarcoding approach. In addition, we used taxon-specific polymerase chain reaction (PCR) primers to screen for bacteria commonly reported in aphid species. As anticipated, all SCA harbored the primary aphid endosymbiont Buchnera aphidicola, an obligate mutualistic bacterial symbiont. Interestingly, none of the secondary symbionts, facultative bacteria typically associated with aphids (e.g., Arsenophonus, Hamiltonella, Regiella) were present in either the metabarcoding data or PCR screens (with the exception of Rickettsiella and Serratia, which were detected by metabarcoding at low abundances <1%). However, our metabarcoding detected bacteria not previously identified in aphids (Arcobacter, Bifidobacterium, Citrobacter). Lastly, we found microbial host-associated differentiation in aphids that seems to correspond to genetically distinct aphid lineages that prefer to feed on grain sorghum (MLL-F) versus sugarcane (MLL-D).

Ticks transmit a wide variety of pathogens including bacteria, parasites and viruses. Over the last decade, numerous novel viruses have been described in arthropods, including ticks, and their characterization has provided new insights into RNA virus diversity and evolution. However, little is known about their ability to infect vertebrates. As very few studies have described the diversity of viruses present in ticks from the Caribbean, we implemented an RNA-sequencing approach on Amblyomma variegatum and Rhipicephalus microplus ticks collected from cattle in Guadeloupe and Martinique. Among the viral communities infecting Caribbean ticks, we selected four viruses belonging to the Chuviridae, Phenuiviridae and Flaviviridae families for further characterization and designing antibody screening tests. While viral prevalence in individual tick samples revealed high infection rates, suggesting a high level of exposure of Caribbean cattle to these viruses, no seropositive animals were detected. These results suggest that the Chuviridae- and Phenuiviridae-related viruses identified in the present study are more likely tick endosymbionts, raising the question of the epidemiological significance of their occurrence in ticks, especially regarding their possible impact on tick biology and vector capacity. The characterization of these viruses might open the door to new ways of preventing and controlling tick-borne diseases.

Relationship between serum levels of cortisol at slaughter and changes of some parameters of meat was investigated in 50 male camels, during ageing for 10 days at 4±1°C. Blood was sampled at slaughter to determine serum levels of cortisol and oblique abdominal external muscle was collected after slaughter to analyze pH, electrical conductivity (EC), drip loss (DL), cooked loss (CL), moisture, solids, ashes, protein total, calcium (Ca), phosphorus (Pi), magnesium (Mg), sodium (Na), potassium (K), catalase activiry (CATa), malondialdehyde (MDA), shrinkage, R-value and total haem pigment (THP) at days 0 (four hours postmortem), 5 and 10 of refrigerated storage. The camels were divided into 3 groups (Gr) with different serum levels of cortisol at slaughter (low, high and very high levels): Gr1 (13.07-67.9 ng/mL, n= 24), Gr2 (80.29-107.21 ng/mL, n= 7) and Gr3 (133.7-198.04 ng/mL, n= 19). Compared to Gr1, Gr2 and Gr3 had a significant (P<0.05) increase of pH, EC, DL, CL, THP, dimensional shrinkage and MDA, and a significant (P<0.05) decrease of CATa at the 5th and 10th postmortem days. However, the bleeding efficiency, moisture, ashes, R-value and levels of Ca, Pi, Na, K and total protein showed no significant differences between twoo cortisol groups. The antemortem circulating levels of cortisol were positively correlated with postmortem pH, EC, DL, CL, THP, dimensional shrinkage and MDA, and negatively correlated with CATa. The analysis of circulating cortisol at slaughtering may predict the quality and oxidant stress status of camel meat during postmortem cold storage.

In ruminants, circulating vitamin D levels may be influenced by photoperiod, nutrition, physiological stage, ambient temperature, attitude and season, whereas, in meat, vitamin D content may be impacted by vitamin D status of animal, ageing and cooking. The information on nutritional value of camel milk and meat is largely available, but, there are very few reports evaluating the vitamin D levels and their variations in blood and these products in the dromedary camel. In this context, this review proposes a gathering of cur-rent knowledge about the vitamin D in this species and discusses findings considering those obtained in other mammal animals.

In genetic control programmes, including the sterile insect technique (SIT), it is crucial to release insects of the highest quality with maximum survival. It is likely that male mosquitoes will follow the trend of other insects in SIT programmes and be stored, transported and eventually released under chilled conditions. The aim of our study was to investigate the impact of different chilling temperatures on male Aedes aegypti and Ae. albopictus survival by exposing them to a range of temperatures for different durations. Ae. aegypti were found to be less sensitive to the impact of chilling, with only 6°C causing a marginal decrease in survival in comparison to non-chilled controls. Conversely, Ae. albopictus displayed a significantly reduced survival at all chilling temperatures even when exposed for a short time. In both species, longer exposure to low temperatures reduced survival. Our results uncovered that Ae. albopictus are more sensitive to chilling, regardless of the temperature, when compared to Ae. aegypti. Such results indicate differences in thermal tolerances between species and the necessity of conducting experiments on a species by species basis when determining temperature limits for any insect destined for release as part of a genetic control programme.

Slaughter stress responses were evaluated in the dromedary camel by analyzing hematocrit (Hct), neutrophil/lymphocyte ratio (NLR), hemolysis (H%), catalase activity (CATa) and plasma levels of cortisol (COR), triiodothyronine (T3), thyroxine (T4), glucose and malondialdehyde (MDA). Blood was collected during three different steps: at the arrival of the animals at the slaughterhouse just after unloading (step 1), at the end of a rest period of 16 to 20 hours (step 2) and finally during bleeding (step 3) after exposure to traditional slaughter stress. NLR, H%, MDA, glucose, COR, T3 and T4 measured at step 2 were significantly (P<0.05) lower compared to those observed at step 1 or step 3. On the contrary, CATa measured at step 2 were significantly (P<0.05) higher than that analyzed at steps 1 and 3. In the camel, the slaughter procedure used here was muchmore stressfuland was able to alter the physiology of the animal.

Cattle trypanosomosis caused by Trypanosoma vivax is a widely distributed disease in Africa and Latin America. It causes significant losses in the livestock industry and is characterized by fluctuating parasitemia, anemia, fever, lethargy, and weight loss. In this study we evaluated the virulence (capacity to multiply inside the host and to modulate the host response) and pathogenicity (ability to produce disease and/or mortality) patterns of two T. vivax strains (TvMT1 and TvLIEM176) in experimentally-infected sheep and determined the proteins differentially expressed in the proteomes of these two strains. Hematological and clinical parameters were monitored in experimentally-infected versus non-infected sheep for 60 days. All the infected animals developed discernable parasitemia at 3 days post-infection (dpi), and the first parasitemia peak was observed at 6 dpi. The maximum average value of parasitemia was 1.3 × 107 (95% CI, 7.9 × 105–2 × 108) parasites/ml in TvLIEM176-infected animals, and 2.5 × 106 (95% CI, 1.6 × 105–4 × 107) parasites/ml in TvMT1-infected ones. Anemia and clinical manifestations were more severe in the animals infected by TvMT1 strain than in those infected by TvLIEM176. In the proteomic analysis, a total of 29 proteins were identified, of which 14 exhibited significant differences in their expression levels between strains. Proteins with higher expression in TvLIEM176 were: alpha tubulin, beta tubulin, arginine kinase, glucose-regulated protein 78, paraflagellar protein 3, and T-complex protein 1 subunit theta. Proteins with higher expression in TvMT1 were: chaperonin HSP60, T-complex protein 1 subunit alpha, heat shock protein 70, pyruvate kinase, glycerol kinase, inosine-5'-monophosphate dehydrogenase, 73 kDa paraflagellar rod protein, and vacuolar ATP synthase. There was a difference in the virulence and pathogenicity between the T. vivax strains: TvLIEM176 showed high virulence and moderate pathogenicity, whereas TvMT1 showed low virulen

Relationship between serum levels of cortisol at slaughter and changes of some parameters of meat was investigated in 50 male camels, during ageing for 10 days at 4±1°C. Blood was sampled at slaughter to determine serum levels of cortisol and oblique abdominal external muscle was collected after slaughter to analyze pH, electrical conductivity (EC), drip loss (DL), cooked loss (CL), moisture, solids, ashes, protein total, calcium (Ca), phosphorus (Pi), magnesium (Mg), sodium (Na), potassium (K), catalase activiry (CATa), malondialdehyde (MDA), shrinkage, R-value and total haem pigment (THP) at days 0 (four hours postmortem), 5 and 10 of refrigerated storage. The camels were divided into 3 groups (Gr) with different serum levels of cortisol at slaughter (low, high and very high levels): Gr1 (13.07-67.9 ng/mL, n= 24), Gr2 (80.29-107.21 ng/mL, n= 7) and Gr3 (133.7-198.04 ng/mL, n= 19). Compared to Gr1, Gr2 and Gr3 had a significant (P<0.05) increase of pH, EC, DL, CL, THP, dimensional shrinkage and MDA, and a significant (P<0.05) decrease of CATa at the 5th and 10th postmortem days. However, the bleeding efficiency, moisture, ashes, R-value and levels of Ca, Pi, Na, K and total protein showed no significant differences between twoo cortisol groups. The antemortem circulating levels of cortisol were positively correlated with postmortem pH, EC, DL, CL, THP, dimensional shrinkage and MDA, and negatively correlated with CATa. The analysis of circulating cortisol at slaughtering may predict the quality and oxidant stress status of camel meat during postmortem cold storage.

In ruminants, circulating vitamin D levels may be influenced by photoperiod, nutrition, physiological stage, ambient temperature, attitude and season, whereas, in meat, vitamin D content may be impacted by vitamin D status of animal, ageing and cooking. The information on nutritional value of camel milk and meat is largely available, but, there are very few reports evaluating the vitamin D levels and their variations in blood and these products in the dromedary camel. In this context, this review proposes a gathering of cur-rent knowledge about the vitamin D in this species and discusses findings considering those obtained in other mammal animals.

Flooded rice fields are ecosystems favorable to growth and production of aquatic organisms. They can even play a major role in feeding and nutrition of local communities, as source of self-recruiting species or supporting production of farmed fish in association with rice. In Madagascar, integrated rice-fish culture has proven a yield net increase, without fertilizers or feed inputs, of more than 10% compared to traditional rice culture. Common carp (Cyprinus carpio), have been either demonstrated to improve rice production through fertilization of rice plots. Fertilization is indeed provided through bioturbation of sediments aside from any confirmed impact on pests and weeds. Although common carp can improve rice production, fish is often limited to small yields (av. 50kg/ha/cycle). Fish yields can however reach 500kg/ha/cycle (av. 100 days) through intensification with fertilizers and feeds. In that context, trophic characterization of rice-fish systems may improve knowledge on ecosystem functioning as well as fish and rice yields. Natural abundances of carbon and nitrogen stables isotopes ratio (δ13C and δ15N) are often used in ecological studies to characterize trophic functioning of aquatic ecosystems. The aim of the current study was therefore, to characterize feeding behavior of common carp in rice fish integrated agriculture to aquaculture system, through stable isotopes analysis of the compartments of this aquatic ecosystem. At the beginning of the experiment, carp larvae signature was -18.8±0.5‰ and 9.3±0.6‰, for δ13C and δ15N respectively. This signature suggest that larvae feeds were supplied by animal proteins (e.g. fish meal) and C4 carbohydrate (e.g. corn). However, following 100 days of extensive feeding in the riceplot, fish signature was depleted compared to larvae, down to -24.9±1.0 and 5.7±0.9‰, for δ13C and δ15N respectively. Stable isotopes signatures of produced fish were in the range of riceplot ecosystem, confirming that feeding was supplied

In genetic control programmes, including the sterile insect technique (SIT), it is crucial to release insects of the highest quality with maximum survival. It is likely that male mosquitoes will follow the trend of other insects in SIT programmes and be stored, transported and eventually released under chilled conditions. The aim of our study was to investigate the impact of different chilling temperatures on male Aedes aegypti and Ae. albopictus survival by exposing them to a range of temperatures for different durations. Ae. aegypti were found to be less sensitive to the impact of chilling, with only 6°C causing a marginal decrease in survival in comparison to non-chilled controls. Conversely, Ae. albopictus displayed a significantly reduced survival at all chilling temperatures even when exposed for a short time. In both species, longer exposure to low temperatures reduced survival. Our results uncovered that Ae. albopictus are more sensitive to chilling, regardless of the temperature, when compared to Ae. aegypti. Such results indicate differences in thermal tolerances between species and the necessity of conducting experiments on a species by species basis when determining temperature limits for any insect destined for release as part of a genetic control programme.

Slaughter stress responses were evaluated in the dromedary camel by analyzing hematocrit (Hct), neutrophil/lymphocyte ratio (NLR), hemolysis (H%), catalase activity (CATa) and plasma levels of cortisol (COR), triiodothyronine (T3), thyroxine (T4), glucose and malondialdehyde (MDA). Blood was collected during three different steps: at the arrival of the animals at the slaughterhouse just after unloading (step 1), at the end of a rest period of 16 to 20 hours (step 2) and finally during bleeding (step 3) after exposure to traditional slaughter stress. NLR, H%, MDA, glucose, COR, T3 and T4 measured at step 2 were significantly (P<0.05) lower compared to those observed at step 1 or step 3. On the contrary, CATa measured at step 2 were significantly (P<0.05) higher than that analyzed at steps 1 and 3. In the camel, the slaughter procedure used here was muchmore stressfuland was able to alter the physiology of the animal.