Live insect larvae were recently proposed for use in laying hens in intensive chicken farming as an innovative form of environmental enrichment. This study aimed to evaluate the effect of laying hen age and feeding with live Black Soldier Fly larvae (BSFL) on egg quality attributes, i.e., chemical composition, fatty acid (FA) profile, and metabolic profile using nuclear magnetic resonance (NMR) spectroscopy. To this aim, 108 Lohman Brown hens were housed in 27 cages (9 replicates per treatment, 4 birds per pen) and monitored between 16 and 34 weeks of age. The hens were split into three experimental groups: a control group fed a commercial diet, and two experimental groups fed the same commercial diet plus 15% or 30% of live BSFL, as fed basis on the expected daily feed intake (DFI). The experimental treatments did not affect the egg and eggshell quality attributes. The supplementation with live BSFL did not influence the chemical composition in terms of macronutrients or the main NMR profiles of egg yolk and albumen. The FA profile of the egg yolk significantly changed as the eggs from hens fed BSFL presented higher rates of SFA and PUFA (P<0.05), lower rate of MUFA (P<0.001), and higher rates of C18:2n 6 (P<0.05) and C18:3 n3 compared to the control eggs (P<0.001). There were no significant differences in the ratio of n-6 to n-3 PUFA. The age of the hens strongly affected egg quality traits (P<0.001), mainly the egg weight, shell weight, shell thickness, eggshell-breaking strength, and eggshell redness (a*) and yellowness (b*), besides the metabolic profile of both egg yolk and albumen. Considering the interaction diet * age of hens, only a few significant effects occurred on egg quality attributes and FA profile. In conclusion, a supplementation with live BSFL up to 30% of DFI may be safely used in laying hen feeding without impairing egg quality.
Paratuberculosis is a chronic disease of ruminants caused by Mycobacterium avium subsp. Paratuberculosis (MAP). Since isolation of MAP type I (S) is rarely reported in Italy, our research was aimed at isolating, by an inexpensive liquid culture manual method, this type of MAP isolates. At first, we used an ELISA to point out to serologically positive samples from five flocks. Secondly, we used a fecal direct IS900-qPCR on the ELISA positive samples, in order to detect shedder animals. Feces from IS900-qPCR positive samples were inoculated in solid and liquid culture media. IS900-qPCR was further used to test the growth of MAP isolates in liquid medium, which were further confirmed by f57-qPCR and submitted to typing by specific PCR in order to identify the MAP type. Twenty-eight samples (24 fecal and four tissutal samples) were processed by culture methods, resulting in the isolation of six type I MAP field isolates. Notably, no isolates were recovered by solid media, underlining the utility of this liquid method. Few data about this type of MAP are currently available in Italy, and further analyses should be carried out in order to study the origin and epidemiology of type I strains circulating in Italy.
Background: Ruminants play an important role in economic sustenance in many developing countries. Abortion is one of the most important causes of economic losses in sheep livestock and, for this reason, it is very important to know, at an early stage, which pathogens caused abortion. Aim: The aim of the study is to obtain data about the distribution of abortifacient pathogens in the Italian regions of Latium and Tuscany, the awareness of the distribution of infectious agents causing abortion could allow the development of an appropriate vaccination and prophylaxis plan, in order to avoid major economic losses. Methods: 388 abortion were collected during 2015-2018 period. Organs, tissues and swabs were subjected to DNA extraction and then analysed with commercial q-PCR kits for the detection of the most common abortion pathogens circulating in these geographical areas. Results: The positivity in 148 abortion was 56% for Chlamydia abortus, 14% for Coxiella burnetii, 16% for Salmonella spp, 12% for Toxoplasma gondii and 2% for Neospora caninum. Interesting results were obtained for cases of abortions with co-infection of abortion pathogens. Conclusion: Diagnosing the cause of abortion remains a multifaceted process that may also include non-infectious factors such as deficiencies and toxicities. Further research is needed also to assess the role of low pathogen concentrations and co-infections in abortions of sheep.
Hermetia illucens, the black soldier fly, is a common and widespread fly of the family Stratiomyidae. Its ability to grow on contaminated substrates suggests the production of antimicrobial peptides that enable its survival. This study aimed to verify the impact of direct and indirect infection with Salmonella enteritidis on the expression of defensins and cecropins in Hermetia illucens larvae. In addition to an infection with a microorganism, it was interesting to verify if the expression of peptides and the relative action of hemolymph changed in larvae subjected to mechanical stress by abdominal puncture. The peptide fraction of the hemolymph of infected larvae was tested using antibiogram and minimum inhibitory concentration tests against Salmonella enteritidis and Salmonella typhimurium. Both molecular and microbiological tests were carried out at three different time points, on larvae not subjected to any treatment (T-0), four hours after treatment (T-1), and 24 h after treatment (T-2). The results of the microbiological tests showed the antimicrobial action of the peptide fraction of the hemolymph against both S. typhimurium and S. enteritidis; for the latter one, the action was more marked. Interesting results were also found for larvae subjected only to mechanical stress by puncture. Molecular tests on the expression of defensins and cecropins were in full agreement with those obtained in the microbiological tests, with expression more pronounced in larvae infected directly with Salmonella enteritidis. Temporal and condition-specific regulation of defensins and cecropins highlights the complexity of the immune response and suggests sophisticated mechanisms by which the host fine-tunes antimicrobial peptide expression to enhance pathogen defense while preventing excessive immune activation.
Toxoplasma gondii is a zoonotic pathogen and the ingestion of tissue cysts by consumption of lamb or mutton has been identified as a possible cause of infection in humans. Many serological surveys in sheep have been performed, showing relevant serological rates; however, while the detection of antibodies indicates an exposure to T. gondii, this does not necessarily imply the presence of tissue cysts in edible tissue. The current study aims to provide further understanding on the occurrence of T. gondii in sheep muscles and the strength of correlation between serological positivity and presence of the parasite in sheep. From 349 sheep, samples (i.e., blood, heart and diaphragm) were collected and subjected to ELISA tests, real-time PCR and histological tests. Despite the high seroprevalence, T. gondii DNA was detected in the heart and/or the diaphragm from 13 out of the 349 tested sheep (3.7%); all were adults (13/191). Furthermore, the histological tests did not reveal the presence of T. gondii tissue cysts in any of the examined portions of interventricular septum. It should be considered that the likelihood of detecting genetic material of the parasite is probably influenced by the uneven distribution of the tissue cysts in the carcass as well as the methodology applied. The findings of this study support the importance of describing the uncertainty associated with the data used for risk assessment to reduce inaccurate estimation or risk overestimation.
1 October 2024 in Journal of Stored Products Research