Search results for " Feeding"
showing 10 items of 277 documents
Dehydrated Sulla forage in dairy ewes feeding: effects on cheese properties
2021
Feeding green sulla forage (GSF) (Sulla Coronarium L.), a shortlived perennial legume containing phenolic compounds, especially condensed tannins, showed to increase intake, milk yield and casein level in ruminants, and enhance fatty acid (FA) profile and antioxidant activity of dairy products. To obtain analogous favourable effects using conserved sulla forage, dehydration could be a valid alternative to the haymaking process which causes greater losses of biomass and its nutritional and bioactive compounds. The aim of this research was to evaluate the dairy products from ewes fed with pelleted dehydrated sulla forage (PDSF) in the diet by comparisons with those obtained using sulla hay (S…
Interaction between stearoyl-coenzyme A desaturase polymorphism and feeding system in affecting the fatty acid profile of sheep cheese
2021
Stearoyl-coenzyme A desaturase (SCD) catalyses the synthesis of monounsaturated fatty acids, by introducing a cis double bond at the delta 9–10 position. The study investigated the effects of a polymorphism at the ovine SCD gene and its interaction with the inclusion of fresh forage in the diet on cheese fatty acid (FA) composition in Valle del Belice ewes. A region of 527 bp of the ovine SCD gene including the partial sequence of the promoter, the complete sequence of the 5’ UTR and exon 1 and the partial sequence of intron 1 were analyzed in order to identify the g.87C > A SNP located in the promoter region. A feeding trial was carried out using 16 Valle del Belice ewes selected on the…
Food partitioning between Serranus scriba and Scorpaena porcus (Perciformes) on the infralittoral ground of the South Tyrrhenian Sea.
1993
Food preferences of Scorpaena porcus and Serranus scriba were investigated from the stomach contents of fish caught with trammel nets in the Gulf of Palermo (Tyrrhenian Sea). Decapoda Natantia and Decapoda Brachyura were the main preferred prey in the diet of S. porcus whereas Decapoda Natantia, Decapoda Galatheidae and Pisces were the preferred prey for S. scriba. These results and the values of the index of overlapping alimentary requirements suggested competition for food resources between the two species. A more precise investigation, at species level, of the food remains of the most abundant taxon (Crustacea Decapoda) made it possible to demonstrate that the trophic niche overlap betwe…
Food selection of a generalist herbivore exposed to native and alien seaweeds
2018
Understanding which factors influence the invasion of alien seaweed has become a central concern in ecology. Increasing evidence suggests that the feeding preferences of native herbivores influence the success of alien seaweeds in the new community. We investigated food selection of a generalist native grazer Paracentrotus lividus, in the presence of two alien seaweeds (Caulerpa cylindracea and Caulerpa taxifolia var. distichophylla) and two native seaweeds (Dictyopteris membranacea and Cystoseira compressa). Sea urchins were fed with six experimental food items: C. cylindracea, C. taxifolia var. distichophylla, a mixture of C. cylindracea and C. taxifolia var. distichophylla, D. membranace…
Diel feeding habits of juveniles of Mullus surmuletus (Linneo, 1758) in the lagoon of the Stagnone di Marsala (Western Sicily, Italy)
1999
Diet composition, feeding rhythm, gastric evacuation rate and daily ration were investigated in juvenile Mulhis surmuletus (Linneo, 1758). Fish were collected in the lagoon of the Stagnone di Marsala in western Sicily, in July 1995, during a 24 h sampling period. Copepoda, Polychaeta, Amphipoda and Tanaidacea were shown to be the most frequent prey items. The feeding index values showed two different daily feeding times. A unimodal trend in the daily rhythm of food consumption was derived, with a peak in feeding between 1200 and 2000 h. Gastric evacuation in juvenile M. surmuletus is best described by an exponential model, with a gastric evacuation rate R = 0.66 g h-1 (r = 0.88) (T = 24.45 …
Arbacia
2020
Arbacia is unique among shallow echinoid genus, not in line with the general rule that sea urchins should be either entirely tropical or entirely temperate, with limited overlap in the subtropics. Six extant Arbacia species have been described by Mortensen. The genus Arbacia has a Neotropical origin and four different fossil species have been described from the Late Miocene. Over the past century, Arbacia has been the subject of intense investigations into the cell biology, toxicology, biochemistry, and embryology. Recently, renewed interest in this genus arose from its phylogeny, ecology, and its resilience to ocean warming and acidification. According to several studies, impacts of ocean …
Trophic Requirements of the Sea Urchin Paracentrotus lividus Varies at Different Life Stages: Comprehension of Species Ecology and Implications for E…
2022
Investigations on trophic requirements of different life cycle stages of Paracentrotus lividus are crucial for the comprehension of species ecology and for its artificial rearing. The future success of echinoculture depends heavily on the development of suitable and cost-effective diets that are specifically designed to maximize somatic growth during the early life stages and gonadal production in the later stages. In this context, a considerable number of studies have recommended animal sources as supplements in sea urchin diets. However, with the exception of Fernandez and Boudouresque (2000), no studies have investigated the dietary requirements over the different life stages of the sea …
Functional traits of two co-occurring sea urchins across a barren/forest patch system
2013
Abstract Temperate rocky reefs may occur in two alternative states (coralline barrens and erect algal forests), whose formation and maintenance are often determined by sea urchin grazing. The two sea urchin species Paracentrotus lividus and Arbacia lixula are considered to play a similar ecological role despite their differing morphological traits and diets. The patchy mosaic areas of Ustica Island, Italy, offer an ideal environment in which to study differences in the performance of P. lividus and A. lixula in barren versus forest states. Results show that the two sea urchin species differ in diet, trophic position, grazing adaptation, movement ability and fitness in both barren and forest…
Size–Abundance Relationships of Freshwater Macroinvertebrates in Two Contrasting Floodplain Channels of Rhone River
2022
Body size is perhaps the most fundamental property of an organism and its relationship with abundance is one of the most studied relationships in ecology. Although numerous studies have examined these relationships in local communities, few have investigated how they vary at different temporal and spatial scales. We investigated the relationship between body size and abundance of local macroinvertebrate communities in two floodplain channels of the French upper Rhone River. The two channels differ in their vegetation coverage (high vs. low vegetation) and hydrological regimes. The shapes of the size–abundance relationship were similar between channels on a yearly basis but differed wh…
Habitat effect on distribution and feeding of Ophidiaster ophidianus (Lmk.) (Asteroidea)
2016
The purple starfish Ophidiaster ophidianus is an Atlanto-Mediterranean starfish protected under the EU’s Habitats Directive. Despite the wide distribution and the current range expansion of this warm affinity species in the northern Mediterranean areas, nothing is known about its diet. Using field observations and carbon (δ13C) and nitrogen (δ15N) stable isotopes, we explored possible changes in density and diet of O. ophidianus in relation to two different Mediterranean habitats: the coralline barren and the macro algae forest. Data were collected at the Marine Protected Area of Ustica Island (Southern Tyrrhenian Sea) from June to September 2009. Starfish density was not affected by the ha…