1,210 research outputs found
Habitat fragmentation and anthropogenic factors affect wildcat Felis silvestris silvestris occupancy and detectability on Mt Etna
Knowledge of patterns of occupancy is crucial for planning sound biological management and for identifying areas which require paramount conservation attention. The European wildcat Felis silvestris is an elusive carnivore and is classified as ‘least concern’ on the IUCN red list, but with a decreasing population trend in some areas. Sicily hosts a peculiar wildcat population, which deserves conservation and management actions, due to its isolation from the mainland. Patterns of occupancy for wildcats are unknown in Italy, and especially in Sicily. We aimed to identify which ecological drivers determined wildcat occurrence on Mt Etna and to provide conservation actions to promote the wildcats’ long-term survival in this peculiar environment. The genetic identity of the wildcat population was confirmed through a scat-collection which detected 22 different wildcat individuals. We analysed wildcat detections collected by 91 cameras using an occupancy frame work to assess which covariates influenced the detection (p) and the occupancy (ψ) estimates. We recorded 70 detections of the target species from 38 cameras within 3377 trap-days. Wildcat detection was positively influenced by the distance to the major paved roads and negatively affected by the presence of humans. Wildcat occupancy was positively associated with mixed forest and negatively influenced by pine forest, fragmentation of mixed forest and altitude. A spatially explicit predicted occupancy map, validated using an independent dataset of wildcat presence records, showed that higher occupancy estimates were scattered, mainly located on the north face and at lower altitude. Habitat fragmentation has been claimed as a significant threat for the wildcat and this is the first study that has ascertained this as a limiting factor for wildcat occurrence. Conservation actions should promote interconnectivity between areas with high predicted wildcat occupancy while minimising the loss of habitat
Camera trapping the European wildcat (Felis silvestris silvestris) in Sicily (Southern Italy): preliminary results
The wildcat is an elusive species that is threatened with extinction in many parts of its range. In Sicily it still lives in a wide range of habitats. During 2006, camera traps were used to investigate the distribution of the wildcat over a 660 ha wide area on the south-western slope of Mount Etna (NE Sicily). Twelve out of 18 trapping stations provided a total of 24 photographs. Nine different individuals were identified using morphological criteria. Our work confirms the suitability of camera trapping for monitoring elusive carnivores
Wild and Farmed Sea Bass (Dicentrarchus Labrax): Comparison of Biometry Traits, Chemical and Fatty Acid Composition of Fillets
Sea bass is a fish widely produced, consumed and appreciated in Italy. Its intensive rearing system provides the consumption of valuable fish to a wider population. Thanks to the use of an appropriate feed, it is possible to obtain reared sea bass which are richer in total lipid with a majority presence of polyunsaturated fatty acids, such as n-3 and n-6 series. In this study, a total of 75 specimens of European sea bass coming from three different origins (two farmed and one wild) were considered, with 25 fish from each origin. Biometry traits were valued as of the chemical and fatty acid profile of fillets. Biometric indices, proximate composition and fatty acid percentage were significantly affected by the rearing system. Fishes from the intensive rearing system (IRS) showed the highest value of relative profile and condition factor, a higher content of lipid and total n-6 that influenced the n-6/n-3 ratio and the atherogenic indexes, and values that indicated their flesh for human consumption as a healthy alternative to the wild fishes
Pig, F1 (wild boar x pig) and wild boar meat quality
Sixteen carcasses of wild boars, pigs, hybrids F1 (wild boar x pig) and reared wild boar have been examined to study the meat quality and the fatty acid composition. Four carcasses came from hunted wild boars and twelve from animals reared in outdoor pens till nine months of age. The meat produced by the hunted wild animals, although not marketable, offers the best quality and nutritional characteristics. The use of hybrids reared in outdoor pens can approximate or equalize the hunted wild boars meat traits. Reared wild boar meat has, in the complex, better compositional characters than hybrids and domestic groups, but acidic quality of fat is not particularly useful for human feeding
A non-invasive monitoring on European wildcat (Felis silvestris silvestris Schreber, 1777) in Sicily using hair trapping and camera trapping: does scented lure work?
An hair trapping protocol, with camera trapping surveillance, was carried out on the south-western side of the Etna, inhabited by an abundant population of the European wildcat. We aimed to collect hair for genetic analysis on the base of a field study conducted in Switzerland, where valerian tincture had been used to attract wildcats to rub again wooden sticks and therefore leaving hairs. We placed 18 hair trapping stations, plus one camera trap per scented wooden stick, 1 km away from each other for 60 days (October 29 2010 to December 28 2010). The rate of "capture" success (1 capture / 24.5 trap-days) by camera trapping was substantially the same as those obtained during previous surveys performed in the same study area without the use of any attractants. No wildcats were photographed while rubbing against the wooden sticks, neither any wildcat was interested in the scent lure. We discuss limitations of the hair trapping, providing possible explanations on the failure of valerian tincture, while suggesting some field advices for future monitorings
Meat quality and lipid fatty acid profile from wild thrush (Turdus philomelos), woodcock (Scolopax rusticola) and starling (Sturnus vulgaris): A preliminary comparative study
Background: The present study aimed to evaluate the nutritional proximate composition, some qualitative traits and fatty acid profile of meat from wild thrush, woodcock and starling hunted in Southern Italy in 2017 and 2018. Methods: Nutritive composition and physical traits of meat and lipid fatty acid profile were evaluated in breast muscle (Pectoralis major) of gamebirds. Results: From findings, the meat pH was significantly (P < 0.001) higher in starling when compared to the other two species. Thrush meat was significantly (P = 0.002) darker and had higher redness (P < 0.001) and yellowness (P = 0.004) in comparison to starling and woodcock. Thrush breast muscle showed the highest (P < 0.001) level of lipids and lowest (P < 0.001) protein content. Meat from thrush showed the best lipid fatty acid profile based on the higher (P < 0.001) monounsaturated fatty acids (MUFA) and lower (P < 0.001) saturated fatty acids (SFA) concentrations. Starling breast muscle reported the highest (P = 0.002) polyunsaturated fatty acids (PUFA) level compared to both thrush and woodcock, whereas no differences were detected on total n-3. The ratio n-6/n-3 was higher (P = 0.001) in starling muscle. Thrush breast muscle had the lowest (P < 0.001) atherogenic and thrombogenic indices compared to the other gamebirds. Conclusions: The findings indicated that meat from the three investigated gamebirds species may represent a healthily lipid food source for human consumption in relation to the prevention of cardiovascular diseases
Effect of an extruded linseed diet on meat quality traits in Nero Lucano pigs
The study aimed to evaluate the effect of a diet containing extruded linseed (Linum usitatissimum L.) on growth performances, carcass traits and meat quality in Nero Lucano pigs. Sixteen male piglets were weaned at about 50 days of age and divided into two homogeneous groups fed a control diet (C) or a diet containing 3% extruded linseed (EL). The trial lasted 32 weeks and pigs were slaughtered at 9 months of age. Samples from the Longissimus dorsi (Ld) muscle were analysed to assess physical and chemical parameters and intramuscular fatty acid composition. Average daily gain, feed intake and feed conversion ratio were not affected by the diet. Pigs fed the C diet showed a significantly greater slaughter weight in comparison to the EL group (116.50 vs 108.25 kg) Meat pH and chemical composition were not influenced by the diet. No differences were found for shear force (WBS) in raw meat, while cooked meat of the EL group showed a lower WBS value. The EL diet significantly lowered total SFA and increased total PUFA, of both n-6 and n-3 series. Among the n-6, significant differences between dietary treatments were found for linoleic acid. As for the n-3 series, EL feeding significantly enhanced linolenic acid, EPA, DPA and DHA. Feeding EL also significantly lowered the PUFA/SFA and n-6/n-3 ratios and the AI and TI, with benefits for human health. In conclusion, dietary supplementation with 3% EL didn't affect growth performance while it improved the fatty acid profile of meat.
Keywords: fatty acid profile, feeding, flaxseed, por
Effect of an extruded linseed diet on meat quality traits in Nero Lucano pigs
The study aimed to evaluate the effect of a diet containing extruded linseed (Linum usitatissimum L.) on growth performances, carcass traits and meat quality in Nero Lucano pigs. Sixteen male piglets were weaned at about 50 days of age and divided into two homogeneous groups fed a control diet (C) or a diet containing 3% extruded linseed (EL). The trial lasted 32 weeks and pigs were slaughtered at 9 months of age. Samples from the Longissimus dorsi (Ld) muscle were analysed to assess physical and chemical parameters and intramuscular fatty acid composition. Average daily gain, feed intake and feed conversion ratio were not affected by the diet. Pigs fed the C diet showed a significantly greater slaughter weight in comparison to the EL group (116.50 vs 108.25 kg) Meat pH and chemical composition were not influenced by the diet. No differences were found for shear force (WBS) in raw meat, while cooked meat of the EL group showed a lower WBS value. The EL diet significantly lowered total SFA and increased total PUFA, of both n-6 and n-3 series. Among the n-6, significant differences between dietary treatments were found for linoleic acid. As for the n-3 series, EL feeding significantly enhanced linolenic acid, EPA, DPA and DHA. Feeding EL also significantly lowered the PUFA/SFA and n-6/n-3 ratios and the AI and TI, with benefits for human health. In conclusion, dietary supplementation with 3% EL didn't affect growth performance while it improved the fatty acid profile of meat
Role of polymeric coating on metallic foams to control the aeroacoustic noise reduction of airfoils with permeable trailing edges
Studies on porous trailing edges, manufactured with open-cell Ni-Cr-Al foams with sub-millimeter pore sizes, have shown encouraging results for the mitigation of turbulent boundary-layer trailing-edge noise. However, the achieved noise mitigation is typically dependent upon the pore geometry, which is fixed after manufacturing. In this study, a step to control the aeroacoustics effect of such porous trailing edges is taken, by applying a polymeric coating onto the internal foam structure. Using this method, the internal topology of the foam is maintained, but its permeability is significantly affected. This study opens a new possibility of aeroacoustic control, since the polymeric coatings are temperature responsive, and their thickness can be controlled inside the foam. Porous metallic foams with pore sizes of 580, 800, and 1200 μm are (internally) spray-coated with an elastomeric coating. The uncoated and coated foams are characterized in terms of reduced porosity, average coating thickness and air-flow resistance. Subsequently, the coated and uncoated foams are employed to construct tapered inserts installed at the trailing edge of an NACA 0018 airfoil. The noise mitigation performances of the coated metal foams are compared to those of uncoated metal foams with either similar pore size or permeability value, and both are compared to the solid trailing edge reference case. Results show that that the permeability of the foam can be easily altered by the application of an internal coating on the metallic foams. The noise reduction characteristics of the coated foams are similar to equivalent ones with metallic materials, provided that the coating material is rigid enough not to plastically deform under flow conditions
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