Evaluation of two artificial infection methods of live ticks as tools for studying interactions between tick-borne viruses and their tick vectors

Up to 170 tick-borne viruses (TBVs) have been identified to date. However, there is a paucity of information regarding TBVs and their interaction with respective vectors, limiting the development of new effective and urgently needed control methods. To overcome this gap of knowledge, it is essential to reproduce transmission cycles under controlled laboratory conditions. In this study we assessed an artificial feeding system (AFS) and an immersion technique (IT) to infect Ixodes ricinus ticks with tick-borne encephalitis (TBE) and Kemerovo (KEM) virus, both known to be transmitted predominantly by ixodid ticks. Both methods permitted TBEV acquisition by ticks and we further confirmed virus trans-stadial transmission and onward transmission to a vertebrate host. However, only artificial feeding system allowed to demonstrate both acquisition by ticks and trans-stadial transmission for KEMV. Yet we did not observe transmission of KEMV to mice (IFNAR−/− or BALB/c). Artificial infection methods of ticks are important tools to study tick-virus interactions. When optimally used under laboratory settings, they provide important insights into tick-borne virus transmission cycles.

Artificial feeding of Ornithodoros fonsecai (Acari: Argasidae) with the anticoagulant Alsever

Ornithodoros fonsecai is a species of argasid tick endemic to Brazil, described in the “São Miguel” cave located in the municipality of Bonito, state of Mato Grosso do Sul, central-western region of Brazil. The artificial feeding technique makes it possible to study the biology of hematophagous arthropods using artificial or natural membranes, as well as different types of blood and anticoagulants. Thus, the aim of the present study was to feed artificially O. fonsecai second instar (N2) nymphs with rabbit blood using parafilm membrane and the anticoagulant Alsever. Ninety percent of the total N2 nymphs engorged and molted to N3 nymphs between 27 and 30 days after feeding, indicating that the use of this anticoagulant is efficient for artificially feeding O. fonsecai N2 nymphs under laboratory conditions.

The Risk Factors for Development of Emergency Conditions in Tender-Age Infants in Acute Intestinal Infections of Different Etiologies

Among the leading risk factors for the development of emergency conditions in acute intestinal infections, especially in infants, some authors point to rickets, anemia, and abnormal antenatal pathology. The aim is to determine the frequency of occurrence of various risk factors for the development of emergency situations in tender-age infants. Materials and methods: 338 tender-age infants with urgent conditions were under observation. The study involved clinical-anamnestic, bacteriological, and serological methods. The aggravating factors were as follows: diseases of parents in 16 (6.2%), related marriages - 20 (7.7%) pregnancy pathology-137 (52.9%), prematurity-16 (6.2%), artificial feeding - 127 (49.0%), early diseases (acute respiratory viral infections, pneumonia, encephalopathy, intestinal infections). Results: According to the results of the study, the central nervous system damage was most often observed in children from 1 month to 6 months (80.2%), anemia was more detected in children of 1-3 years - 56.4%, rickets was more diagnosed in children aged 6-12 months -38.2%.

Investigation of Transovarial Transmission of Bartonella henselae in Rhipicephalus sanguineus sensu lato Ticks Using Artificial Feeding

Bartonella henselae is a slow-growing, Gram-negative bacterium that causes cat scratch disease in humans. A transstadial transmission of the bacteria from larvae to nymphs of Rhipicephalus sanguineus sensu lato (s.l.) ticks, suspected to be a potential vector of the bacteria, has been previously demonstrated. The present study aims to investigate transovarial transmission of B. henselae from R. sanguineus s.l. adults to their instars. Adult ticks (25 males and 25 females) were fed through an artificial feeding system on B. henselae-infected goat blood for 14 days, and 300 larvae derived from the experimentally B. henselae-infected females were fed on noninfected goat blood for 7 days. Nested PCR and culture were used to detect and isolate B. henselae in ticks and blood samples. Bartonella henselae DNA was detected in midguts, salivary glands, and carcasses of the semi-engorged adults and pooled tick feces (during feeding and post-feeding periods). After the oviposition period, B. henselae DNA was detected in salivary glands of females (33.3%), but not in pooled eggs or larvae derived from the infected females. However, B. henselae DNA was detected by nested PCR from the blood sample during larval feeding, while no viable B. henselae was isolated by culture. According to our findings, following infected blood meal, B. henselae could remain in the tick midguts, move to other tissues including salivary glands, and then be shed through tick feces with limited persistency. The presence of bacterial DNA in the blood during larval feeding shows the possibility of transovarial transmission of B. henselae in R. sanguineus s.l. ticks.

Biofloc Microbiome With Bioremediation and Health Benefits

The biofloc system has recently attracted great attention as a cost-effective, sustainable, and environmentally friendly technology and expected to contribute toward human food security (Zero Hunger SDG 2). It is also expected that this endeavor can be adopted widely because of its characteristics of zero water exchange and reduced artificial feeding features. In the biofloc system, the flocs which are generally formed by aggregation of heterotrophic microorganisms, serve as natural bioremediation candidates. These microbes effectively maintain water quality by utilizing the nutrient wastes, mostly originated from digested, unconsumed, and metabolic processes of feed. Additionally, the flocs are important sources of nutrients, mainly a protein source, and when these are consumed by aquaculture animals they improve the growth performance, immunity, and disease tolerance of host against pathogenic microbial infection. Here in this review, we focus on recent advances that could provide a mechanistic insight on how the microbial community developed in the biofloc system helps in the bioremediation process and enhances the overall health of the host. We have also tried to address the possible role of these microbial communities against growth and virulence of pathogenic microbes.

Management of Low Birth Weight in Canine and Feline Species: Breeder Profiling

Low birth weight (LBW) has been identified as a major risk factor for neonatal mortality in many species. The aim of this survey was to determine the profiles of canine and feline breeders concerning their perceptions of, and management practices relating to, LBW individuals. An anonymous online survey was addressed to French cat and dog breeders in September 2019 via social networks. Multiple correspondence analysis and hierarchical clustering were used to explore breeders’ profiles. Three clusters were identified among the 649 breeders included in this analysis. Cluster 1 (49%) included dog and cat breeders who weighed newborns (and thus identified LBW) and controlled nursing by the dam (controlled suckling) but did not warm them up. Cluster 2 breeders (21%) of both species did not weigh puppies or kittens to identify LBW or to monitor the evolution of their weight afterwards. Cluster 3 (30%) including mostly cat breeders who weighed neonates routinely as in Cluster 1, but they practiced artificial feeding rather than controlled suckling. This survey provides a basis for better understanding of perceptions and practices regarding LBW puppies and kittens. It will be useful to provide guidelines for neonatal management to increase their chances of survival.

Plasmodium metabolite HMBPP stimulates feeding of main mosquito vectors on blood and artificial toxic sources

Recent data show that parasites manipulate the physiology of mosquitoes and human hosts to increase the probability of transmission. Here, we investigate phagostimulant activity of Plasmodium-metabolite, (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMBPP), in the primary vectors of multiple human diseases, Anopheles coluzzii, An. arabiensis, An. gambiae s.s., Aedes aegypti, and Culex pipiens/Culex torrentium complex species. The addition of 10 µM HMBPP to blood meals significantly increased feeding in all the species investigated. Moreover, HMBPP also exhibited a phagostimulant property in plant-based-artificial-feeding-solution made of beetroot juice adjusted to neutral pH similar to that of blood. The addition of AlbuMAXTM as a lipid/protein source significantly improved the feeding rate of An. gambiae s.l. females providing optimised plant-based-artificial-feeding-solution for delivery toxins to control vector populations. Among natural and synthetic toxins tested, only fipronil sulfone did not reduce feeding. Overall, the toxic-plant-based-artificial-feeding-solution showed potential as an effector in environmentally friendly vector-control strategies.

Estimating the Willingness to Pay for Eco-Labeled Products of Formosan Pangolin (Manis pentadactyla pentadactyla) Conservation

Pangolins are currently the most smuggled mammals in the world. Meanwhile, Taiwan has demonstrated the world’s first case of the use of artificial feeding to raise pangolins to adulthood. The government has also begun to cooperate with farmers in pangolin-spotted areas. Agricultural products can earn the green label once they have passed the evaluation. The challenge is that very few farms have obtained the pangolin-friendly label so far. Our hypothesis is that farmers lack the knowledge that consumers would pay additional money for products that are labeled pangolin-friendly compared to regular ones. Thus, farmers have an insufficient incentive to apply for this label. This research aims to fill this gap by providing people with the necessary knowledge. Contingent valuation with the single-bounded dichotomous choice format was used, which involved investigating 417 valid observations. We found the following: (1) customers are willing to pay about 8.06 USD for pangolin-friendly rice (an increase of 397% in relation to the mean price of rice); (2) customers are willing to pay for about 11.46 USD for pangolin-friendly tea (an increase of 179% in relation to the mean price of tea); and (3) customers are willing to pay about 25.81 USD for pangolin-friendly coffee (an increase of 509% in relation to the mean price of coffee). Our findings give farmers more incentive to conduct eco-friendly production. Consequently, the quality of agricultural products as well as the habitats of endangered pangolins improve. Thus, consumers’ health, the environment, and the future of pangolin conservation can benefit in this attempt to achieve sustainability.