Chemical trails and the parasites that follow them

A review of black soldier fly (Hermetia illucens) as a potential alternative protein source in broiler diets

Since per capita global meat utilization is predicted to increase to 40% from 2019 to 2050, global use of cultivable land in livestock, poultry, and feed production is 30%. Use of alternative protein sources as animal feed can be a solution to minimize cropland usage in conventional feed production. Commonly used protein sources in animal diets like soybean meal and fish meal are facing challenges of high demand, but the current production might not fulfill their dire need. To overcome this issue, the discovery of alternative protein sources is the need of the hour, insect meals like black soldier fly (BSF) are one of these alternative protein sources. These flies are non-infectious, bite-less, can convert the variant types of organic waste (food wastes, animal and human excreta) proficiently into rich profile biomass with reduced harmful bacteria count and do not serve as a vector in disease transmission. Based on the substrate used, the BSF larvae protein, fat and ash contents vary from 37-63%, 7-39% and 9-28% on dry matter basis, respectively. Previous studies have reported that using BSF and its byproducts as alternative protein sources in broiler diets with partial or complete replacement of conventional protein sources. In this review, a brief introduction to insect meal, BSF origin, life cycle, nutritional profile, influences on growth performance, carcass characteristics, fatty acid profile of meat, biochemical properties of blood, gut morphology and microbiota of the caecum along with its influence on laying performance of layers has been discussed in detail. Studies have concluded the partial replacement of conventional protein sources with BSF is possible, whereas complete replacement may cause poor performance due to reduced digestibility up to 62% attributable to chitin content (9.6%). Further studies to corroborate the effect of dietary BSF on growth performance, carcass characteristics, fatty acid profile of meat, and gut morphology and caecum microbiota are required to standardize the inclusion levels in feeds for higher performance of poultry.

Protozoan and helminth parasite fauna of free-living Croatian wild wolves (Canis lupus) analyzed by scat collection

The European wolf (Canis lupus) is a large carnivore species present in limited areas of Europe with several small populations still being considered as endangered. Wolves can be infected by a wide range of protozoan and metazoan parasites with some of them affecting free-living wolf health condition. On this account, an epidemiological survey was conducted to analyze the actual parasite fauna in Croatian wild wolves. In total, 400 individual faecal samples were collected during field studies on wolf ecology in the years 2002-2011. Parasite stages were identified by the sodium acetate acetic acid formalin (SAF)-technique, carbolfuchsin-stained faecal smears and Giardia/Cryptosporidium coproantigen-ELISAs. A subset of taeniid eggs-positive wolf samples was additionally analyzed by PCR and subsequent sequencing to identify eggs on Echinococcus granulosus/E. multilocularis species level. In total 18 taxa of parasites were here detected. Sarcocystis spp. (19.1%) occurred most frequently in faecal samples, being followed by Capillaria spp. (16%), ancylostomatids (13.1%), Crenosoma vulpis (4.6%), Angiostrongylus vasorum (3.1%), Toxocara canis (2.8%), Hammondia/Neospora spp. (2.6 %), Cystoisospora ohioensis (2.1%), Giardia spp. (2.1%), Cystoisospora canis (1.8%), Cryptosporidium spp. (1.8%), Trichuris vulpis (1.5%), Taenia spp. (1.5%), Diphyllobothrium latum (1.5%), Strongyloides spp. (0.5%), Opisthorchis felineus (0.5%), Toxascaris leonina (0.3%), Mesocestoides litteratus (0.3%) and Alaria alata (0.3%). Some of the here identified parasites represent relevant pathogens for wolves, circulating between these carnivorous definitive hosts and a variety of mammalian intermediate hosts, e. g. Taenia spp. and Sarcocystis spp., while others are considered exclusively pathogenic for canids (e.g. A. vasorum, C. vulpis, T. vulpis, Cystoisospora spp.). This study provides first records on the occurrence of the two relevant anthropozoonotic parasites, Giardia spp. and Cryptosporidium spp., in wild wolves from Croatia.