Chromium content in the meat of male Saanen goat kids from Vojvodina (Northern Serbia)

Goats, the earliest ruminant to be domesticated, are traditional sources of meat, milk, fibre, leather, related products of animal origin and as draught and pack animals. Meat is the major product of the goat. Meat quality is the sum of all sensory, nutritive, technological and hygienic-toxicological factors of meat. The aims of this study were to investigate the chromium content of four different muscles (M. psoas major, M. longissimus dorsi, M. semimembranosus and M. triceps brachii) of Saanen goat male kids and to determine whether the chromium contents differed between the muscles. Chromium content was determined using inductively coupled plasma optical emission spectrometry (ICP-OES), after dry ashing mineralisation. The studied muscles did not significantly differ (P >0.05) with respect to chromium content. The chromium content ranged from 0.012 to 0.067 mg/100 g, with an average of 0.026 mg/100 g

Factors Affecting Population Dynamics of Maternally Transmitted Endosymbionts in Bemisia tabaci

While every individual of Bemisia tabaci (Hemiptera: Aleyrodidae) harbors the primary symbiont (P-symbiont) Portiera, the infection frequencies of the six secondary symbionts (S-symbionts) including Hamiltonella, Arsenophonus, Cardinium, Wolbachia, Rickettsia and Fritschea vary greatly among different populations. To characterize the factors influencing the infection dynamics of the six S-symbionts in B. tabaci, gene-specific PCR were conducted to screen for the presence of the P-symbiont Portiera and the six S-symbionts in 61 (17 B and 44 Q biotypes) field populations collected from different plant species and locations in China. All individuals of the 61 populations hosted the P-symbiont Portiera, but none of them harbored Arsenophonus and Fritschea. The presence and infection rates of Hamiltonella, Cardinium, Rickettsia, Wolbachia and their co-infections Rickettsia + Hamiltonella (RH), Rickettsia + Cardinium (RC), Hamiltonella + Cardinium (HC) and Rickettsia + Hamiltonella + Cardinium (RHC) varied significantly among the 61 field populations; and the observed variations can be explained by biotypes, sexes, host plants and geographical locations of these field populations. Taken together, at least three factors including biotype, host plant and geographical location affect the infection dynamics of S-symbionts in B. tabaci

Fitness costs of infection with Serratia symbiotica are associated with greater susceptibility to insecticides in the pea aphid Acyrthosiphon pisum

Background: Aphids are agricultural pests that damage crops by direct feeding and by vectoring important plant viruses. Bacterial symbionts can influence aphid biology, e.g. by providing essential nutrients or facilitating adaptations to biotic and abiotic stress. Results: We investigated the pea aphid (Acyrthosiphon pisum Harris) and its commonly associated secondary bacterial symbiont Serratia symbiotica to study the effect of this symbiont on host fitness and susceptibility to the insecticides imidacloprid, chlorpyrifos methyl, methomyl, cyantraniliprole and spirotetramat. There is emerging evidence that members of the genus Serratia can degrade and/or detoxify diverse insecticides. Therefore, we hypothesized that S. symbiotica may promote resistance to these artificial stress agents in aphids. Our results showed that Serratia‐infected aphids were more susceptible to most of the tested insecticides than non‐infected aphids. This probably reflects the severe fitness costs associated with S. symbiotica, which negatively affects development, reproduction and body weight. Conclusion: Our study demonstrates that S. symbiotica plays an important role in the ability of aphid hosts to tolerate insecticides. These results provide insight into the potential changes in tolerance to insecticides in the field because there is a continuous and dynamic process of symbiont acquisition and loss that may directly affect host biology

Orally delivered scorpion antimicrobial peptides exhibit activity against Pea Aphid (Acyrthosiphon pisum) and its bacterial symbionts

Aphids are severe agricultural pests that damage crops by feeding on phloem sap and vectoring plant pathogens. Chemical insecticides provide an important aphid control strategy, but alternative and sustainable control measures are required to avoid rapidly emerging resistance, environmental contamination, and the risk to humans and beneficial organisms. Aphids are dependent on bacterial symbionts, which enable them to survive on phloem sap lacking essential nutrients, as well as conferring environmental stress tolerance and resistance to parasites. The evolution of aphids has been accompanied by the loss of many immunity-related genes, such as those encoding antibacterial peptides, which are prevalent in other insects, probably because any harm to the bacterial symbionts would inevitably affect the aphids themselves. This suggests that antimicrobial peptides (AMPs) could replace or at least complement conventional insecticides for aphid control. We fed the pea aphids (Acyrthosiphon pisum) with AMPs from the venom glands of scorpions. The AMPs reduced aphid survival, delayed their reproduction, displayed in vitro activity against aphid bacterial symbionts, and reduced the number of symbionts in vivo. Remarkably, we found that some of the scorpion AMPs compromised the aphid bacteriome, a specialized organ that harbours bacterial symbionts. Our data suggest that scorpion AMPs holds the potential to be developed as bio-insecticides, and are promising candidates for the engineering of aphid-resistant crops