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Muscle Fibre Types and Their Relation to Meat Quality Traits in Pigs

Abstract

The authors have been studying various characteristics of muscle fibres and their relationship to the meat quality parameters for many years. However, the conclusions drawn by researchers often differ. A higher proportion of glycolytic IIB fibres in pig muscles is usually related to paler meat with lower water holding capacity. On the other hand the relationship between muscle fibres and meat texture parameters is not clear. Studies using immunohistochemistry methods that allow a more detailed classification of individual muscle fibre types could bring new findings in this area. It would thus be possible to influence muscle fibre type composition in the muscle to achieve the desired meat quality using various extrinsic and intrinsic factors. The main aim of this review is to summarise current knowledge on the description of muscle fibres typology and the effect of their morphological traits on pork meat quality.

Open access
Nematicidal Effect of Organic Extract Metal Complex on Meloidogyne incognita Infecting Groundnuts (Arachis hypogea)

Abstract

The control of plant parasitic nematodes is constantly associated with environmental pollution problems which emanates from the ability of synthetic nematicides to bind strongly to different soil types owing to their hydrophilic nature. This research attempted to determine the nematicidal potential of copper, iron and zinc salts complexed with methanolic extract of Enantia chloranta on Meloidogyne incognita infecting groundnut plants on the field. Carbofuran, a synthetic nematicide was used as a reference standard. The experiment was a randomised complete block design which was conducted in two raining seasons (2017 & 2018). Two grams (2 g) of each of the metal salts were reacted with 300 ml of E. chloranta methanolic extract. Good nematicidal activity was displayed by E. chloranta crude extract copper complex (ENCT/CuSO4) close to the value obtained with carbofuran (CBFN), iron and zinc salt complexes (ENCT/FeSO4 and ENCT/ZnSO4) were also significantly (p<0.05) effective. Toxicity of the metal salt complex to M. incognita was dose dependent. Vegetative growth and yield was significantly (p<0.05) higher in plants treated with the highest concentration of the metal complex solution. Significantly lower nematode population was seen at harvest in the roots of treated plants as opposed to the untreated plants. This research has demonstrated that the E. chloranta metal complex is a promising nematicidal substance.

Open access
A new root-knot nematode, Meloidogyne moensi n. sp. (Nematoda: Meloidogynidae), parasitizing Robusta coffee from Western Highlands, Vietnam

Summary

A new root-knot nematode, parasitizing Robusta coffee in Dak Lak Province, Western Highlands of Vietnam, is described as Meloidogyne moensi n. sp. Morphological and molecular analyses demonstrated that this species differs clearly from other previously described root-knot nematodes. Morphologically, the new species is characterized by a swollen body of females with a small posterior protuberance that elongated from ovoid to saccate; perineal patterns with smooth striae, continuous and low dorsal arch; lateral lines marked as a faint space or linear depression at junction of the dorsal and ventral striate; distinct phasmids; perivulval region free of striae; visible and wide tail terminus surrounding by concentric circles of striae; medial lips of females in dumbbell-shaped and slightly raised above lateral lips; female stylet is normally straight with posteriorly sloping stylet knobs; lip region of second stage juvenile (J2) is not annulated; medial lips and labial disc of J2 formed dumbbell shape; lateral lips are large and triangular; tail of J2 is conoid with rounded unstriated tail tip; distinct phasmids and hyaline; dilated rectum. Meloidogyne moensi n. sp. is most similar to M. africana, M. ottersoni by prominent posterior protuberance. Results of molecular analysis of rDNA sequences including the D2–D3 expansion regions of 28S rDNA, COI, and partial COII/16S rRNA of mitochondrial DNA support for the new species status.

Open access
Nutrient Digestibility of Wheat in Rats and Chickens Depending on the Rye 1B/1R Translocation of Wheat Varieties

Abstract

A major part of wheat production is channelized towards animal feed. In the present experiment, we first aimed to determine the relationship of the crude protein (CP) content and the individual fractions (albumin + globulin, gliadin, glutenin) of wheat varieties (with or without the rye translocation 1B/1R) with the digestibility, feed intake, feed conversion, and protein efficiency ratio (PER) of the feed in ROSS 308 chicken broilers. Secondly, we determined the CP content, biological value, net protein utilization, and effect of various fibre components of the same wheat lines in Wistar rats. Seven out of sixteen wheat varieties studied herein included the 1B/1R translocation. Nutritional values were evaluated by the Weende analysis using the Kjeldahl and the Henneberg–Stohmann methods. Moreover, acid detergent fibre and neutral detergent fibre contents, CP digestibility and PER were determined. In broiler chickens, no statistically significant differences were found. In rats, however, the presence of 1B/1R significantly increased the CP content, affecting the nutritional value. This should be considered prior to the indiscriminate use of otherwise undesirable wheat varieties as animal feed.

Open access
Occurrence of Enterocin Genes in Enterococci from Slovak Milk Product Žinčica

Abstract

Žinčica is a popular Slovak dairy product made from ewes’ milk. It is a by-product resulting during ewes’ lump cheese processing. Microbiota in Žinčica have rarely been studied, especially enterococci; however, they can produce beneficial substances – bacteriocins. In this study, the presence of Enterocins (Ents) genes were analysed in enterococci from Žinčica and partially also the inhibition activity. Samples of Žinčica were collected from different agrofarms producing ewes’ lump cheese (34) in Central Slovakia. In the enterococci tested, Ent P gene was the most frequently detected (in 6 out of 7 enterococci), followed by Ent A and Ent L50B genes. Ent B gene was detected only in E. faecium 30E1. On the other hand, E. faecalis 31E2 did not contain Ent genes, although it showed inhibition activity against the indicator strains Enterococcus avium EA5, Staphylococcus aureus SA5, Listeria monocytogenes CCM4699 (inhibition zone sizing up to 20 mm). E. faecium 30E1 contained genes of four Ents; however, it showed no inhibition activity. Growth of the four indicators was inhibited due to the antimicrobial activity of E. faecium 32E1 with Ent P gene detection. This is the first study reporting on the occurrence of Ent genes in enterococci from Žinčica.

Open access
Participation Rates of Freshwater Recreational Fisheries in the Counties of Croatia

Abstract

The aim of this research was to define the participation rates of freshwater anglers in Croatia, their changes over the years and their differences across the counties of Croatia. In spite of a continuous population decline ever since Croatia joined the EU, the number of anglers has slightly increased to around 1%. The counties can be divided into three groups – counties on the Adriatic coast where marine fisheries are dominant, a very urbanized City of Zagreb and the remaining inland counties. In freshwater recreational fisheries in Croatia, the tradition and availability of fishing grounds dominate the participation rate of anglers. However, there are indications of the influence of GDP values so the counties with GDP over 6,500 euros per capita expressed positive relationship to the percentage of anglers (p<0.05). On the other hand, densely populated county of the City of Zagreb confirms that urbanization and much higher GDP result in a much lower percentage of recreational fishermen.

Open access
Pilot Tests and Fouling Identification in the Ultrafiltration of Model Oily and Saline Wastewaters

Abstract

This paper evaluates ceramic membrane performance and fouling mechanisms in the ultrafiltration of model oil-in-water solutions with addition of NaCl. First, the work estimated the effect of main process parameters, i.e. transmembrane pressure, cross-flow velocity and NaCl content in the feed on oil rejection and permeate flux using 23 experimental design. The ultrafiltration experiments were carried out using pilot installation with commercial tubular ceramic 300 kDa membrane. Ultrafiltration data obtained using experimental design technique was used to determine the regression coefficients of polynomial equations. These equations give information on non-conjugated as well as conjugated effects of two operating parameters and one feed parameter on ceramic membrane performance in ultrafiltration process of model oil-in-water-NaCl solutions. Moreover, these equations can help to determine optimal conditions for ultrafiltration process from the point of view of membrane permeability and selectivity. Next, ultrafiltration results were analyzed using resistance-in-series model. It was found that the process is membrane resistance limited. It was also stated that, resistance caused by reversible fouling is greater than irreversible fouling resistance. Finally, pore blocking models based on modified Hermia’s equation were used to determine membrane fouling mechanism responsible for permeate flux decline with ultrafiltration time. In investigated system ceramic membrane fouling was caused by complete and intermediate pore blocking mechanisms.

Open access
Population changes in former voivodeship cities in Poland in the context of suburbanization processes and loss of the administrative function

Abstract

The article presents an attempt to analyse population changes and to measure the strength of the impact of factors causing these changes in former voivodeship (province) cities in Poland. In view of the ongoing processes of suburbanisation, the discussion also concerns the areas surrounding the city, i.e. those creating urban systems together with the city. These zones were delineated, calling them demographic influence zones, because only demographic factors were involved in defining them. The research was conducted in the period between1999–2015, and took into account the administrative reform of the country that degraded 31 cities from voivodeship (NUTS-2) capitals to poviat (LAU-1) cities. The main aim of the study was to find an answer to the question: do the directions and the strength of population changes confirm a hypothesis of the destructive impact of the loss of administrative function on settlement units. The results of the study only partially confirmed this hypothesis. Although a decrease in the population is overwhelmingly predominant in the city core, in the case of the demographic influence zone, it has already increased. Counting both parts together, it was found that in half of the cases there was a decline and in the other half a growth of the population.

Open access
The Possibility of Utilization of Sewage Sludge as a Filler in Production of the Lightweight Aggregate Concrete

Abstract

The article presents the laboratory investigations of the basic thermal and hygric parameters of standard lightweight aggregate-concrete and lightweight aggregate-concrete supplemented with municipal sewage sludge. Both types of concrete are based on light aggregates, commonly used in the Polish building market. In order to improve the hygric parameters of the material, such as water absorptivity, the admixture of water emulsion of reactive polisiloxanes was applied. Within the presented research, together with basic moisture parameters estimation, capillary rise process was monitored using Time Domain Reflectometry (TDR) modified sensors. Hygric parameters were supplemented with the estimation of thermal conductivity coefficient λ determined using stationary method. The analysis of thermal and hygric properties of concrete confirmed the applicability of lightweight aggregate-concrete with sewage sludge supplementation for further production.

Open access
Post-Coagulation Sludge as an Adsorbent of Dyes from Aqueous Solutions

Abstract

The main source of usable water supply in Poland is surface water. The most frequently used methods of surface water treatment are coagulation and filtration processes. During these processes post-coagulation sludge is generated, which is the main waste produced in water treatment plants. This sludge is characterized by an amorphous structure with a strongly developed specific surface, similar to sewage sludge. Dried and crushed post-coagulation sludge was used in the studies as an adsorbent of two acid dyes: Acid Red 18 (AR 18) and Acid Green 16 (AG 16). The most favourable pH of process and contact time as well as sorption isotherm were established. For both dyes the most favourable pH value was equal 2. The tests showed that in the case of AR 18 (180 min) a longer contact time was necessary to reach the equilibrium than for AG 16 (120 min). Moreover, based on the different isotherm two-parameter models, the sorption capacity, type of sorption and energy of sorption were calculated based on linear and non-linear regression. The tests showed that in the case of dye AG 16 monolayer sorption occurred - the analysis showed better fitting the results to Langmuir model. Moreover, for both dyes, physical adsorption took place - it was indicated by the values of parameter 1/n (computed from the Freundlich model).

Open access