Search Results

1 - 8 of 8 items

  • Author: Piotr Domaradzki x
Clear All Modify Search

Abstract

The aim of the study was to discuss breeding of pigs of the Puławska breed, which is included in a Genetic Resources Conservation Programme, and to analyse performance parameters that are useful in domestic pig production. The Puławska breed is the oldest native breed of pig in Poland. Since 1996 it has been protected by a genetic resources conservation programme, owing to breeding traditions and the production traits characteristic of the breed. The use value of these pigs is currently at the level of maternal breeds: number of live piglets born per litter – 10.54; number of piglets reared per litter – 9.37; daily weight gains – 569 g for breeding boars and 562 g for breeding gilts; meat content – 54.6% for breeding boars and 54.9% for breeding gilts. An important element in favour of the use of this breed in domestic production of fresh pork and pork products is its meat quality parameters. The mean values for physical traits (WHC 22.42%, pH45 6.47, pH24 5.63) and chemical parameters (protein 22.70%, fat 2.65%) are characteristic of meat of normal quality. The Puławska breed can be used to produce high-quality fresh meat and meat products, including traditional and regional ones. Puławska pigs are bred and reared according to the principles of sustainable agriculture, which reduces the negative impact of pig production on the natural environment.

Abstract

Transparent conducting oxide (TCO) films of indium-tin-oxide were evaporated on the surface of silicon wafers after phosphorous diffusion and on the reference glass substrates. The influence of deposition process parameters (electron beam current, oxygen flow and the substrate temperature) on optical and electrical properties of evaporated thin films were investigated by means of resistivity measurements and optical spectrophotometry. The performance of prepared thin films was judged by calculated figure of merit and the best result was obtained for the sample deposited on the substrate heated to the 100 °C and then removed from the deposition chamber and annealed in an air for 5 minutes at 400 °C. Refractive index and extinction coefficient were evaluated based on measured transmission spectra and used for designing of antireflection coating for solar cell. The obtained results showed that prepared TCO thin films are promising as a part of counter electrode in crystalline silicon solar cell construction.

Slaughter Value of Young Polish Black-and-White, White-Backed, Polish Holstein-Friesian and Limousin Bulls Under Semi-Intensive Fattening

The objective of the present study was to compare the slaughter value of young bulls of two breeds included in the genetic resources conservation programme, namely Polish Black-White and White-backed with young Polish Holstein-Friesian (dairy type) and Limousin (beef type) bulls. This is the first study to evaluate the meat performance traits of White-backed cattle in several-centuries history of the breed in Poland. It was determined that populations of White-backed and Polish Black-and-White cattle represent the dual-purpose type desirable in the genetic resources conservation programme. The indices obtained for the analysed traits of slaughter value from young Polish Black-and-White and White-backed bulls were intermediate between Polish Holstein-Friesian (dairy type) and Limousin (beef type), but closer to those of the Polish Holstein-Friesian breed. The analysed muscles of young bulls had a very similar content of basic chemical components. The relatively high amount of proteins (22.85-23.23%) in musculus longissimus lumborum and in musculus semintendinosus (22.43-23.06%) should be emphasized.

Abstract

The aim of the research was to evaluate the influence of calf age on proximate composition, fatty acid composition and mineral contents, as well as postmortem ageing under vacuum on the inherent properties of musculus longissimus lumborum of Limousin suckler beef aged to 6, 7 or 8 months. The moisture, protein, fat, and ash content, fatty acid composition, mineral concentrations and intrinsic properties (pH, electrical conductivity, drip and cooking loss, shear force, and CIE colour parameters) were determined. The calf age significantly (P≤0.05) correlated with an increased protein content and energy value of meat and decreased water:protein proportion. Moreover, increased age correlated with higher concentrations of Mg (P≤0.01), Zn and Fe (P≤0.05) and reduced concentrations of Cu (P≤0.05). The fatty acid composition was similar irrespective of calf age, with the exception of CLA content, which was significantly (P≤0.01) reduced in older animals. Muscles of calves aged 6 months were significantly lighter, less red, and showed the most significant drip loss compared to the muscles of older animals. There was no significant (P>0.05) interaction between calf age and postmortem ageing for the intrinsic properties analysed. Postmortem ageing under vacuum resulted in a significant decrease (P≤0.05) in the shear force of meat (irrespective of the age of the calves). The lack of significant differences, especially with regard to the meat pH, shear force, fatty acid composition, and with the significantly higher content of protein and major elements (Fe, Mg and Zn) in relation to the slaughter age, indicates the validity of increasing the duration of fattening of the Limousin calves reared with their mothers on the pasture until the age of 8 months, which is a maximum in this category.

Abstract

An evaluation was conducted of the suitability for fattening in a semi-intensive system (mainly with fodders from permanent grassland) and the slaughter value of 15 young bulls of the Polish Red (PR) breed and 10 each of the White-Backed (WB) and Polish Black-and-White (BW) breeds. The reference group consisted of young bulls of the Black-and-White variety of the Polish Holstein- Friesian (HF) breed and the Simmental (SIM) breed, fattened on the same farms. Control fattening was carried out until the age of 18 months. Mean daily weight gain in the bulls of the native breeds during the control fattening period (which lasted 314-358 days) was 0.9 kg, similarly to HF, but significantly lower (P≤0.05) than in the Simmentals (986 g). During the entire fattening period, i.e. from birth to the age of 18 months, daily weight gain was 832 g in PR and 889-919 g in WB and BW. Dressing percentage was lowest in PR bulls (51.69%), and higher in WB (53.1%) and BW (53.49%), with values similar to the reference group, i.e. young bulls of the Simmental (52.97%) and HF (53.29%) breeds. The difference between PR and BW (1.8%) and HF (1.6%) was statistically significant (P≤0.05). In the EUROP classification system, the carcasses of the young bulls of the native breeds were most often placed in classes R- and O+ (conformation) and 2+ and 3- (fat cover), as in the case of young HF bulls. Carcasses of young Simmental bulls were assigned to much higher classes. The young bulls of the three Polish native breeds evaluated are good material for fattening in a semi-intensive system (mainly with fodder from permanent grasslands), while the young PR bulls were the least suitable

Abstract

The material for the study consisted of 80 samples taken from the longissimus lumborum (LL) and semitendinosus (ST) muscles of young bulls of five breeds (8 samples of each muscle per breed), including three native breeds included in the genetic resources conservation programme, i.e. Polish Red, White-Backed and Polish Black-and-White, which together with the Simmental and Polish Holstein-Friesian breeds. The content of the elements (K, Na, Mg, Ca, Zn, Fe, Mn, and Cu) analysed in the meat of the young bulls (fattened in a semi-intensive system on fodder from permanent grassland) was found to depend (in varying degrees) on the breed of cattle. The greatest differences (P<0.01 and P<0.05) were noted between the Polish Holstein-Friesians (PHF) and the remaining breeds, mainly in the content of Mg, Ca, Zn and Mn. The results obtained in the four other breeds for most of the macro- and microelements were more uniform, with the highest content noted in the muscles of the young bulls of the native breeds.

Abstract

Thin films were deposited using modified, high energy magnetron sputtering method from Ti-Nd mosaic targets. The amount of neodymium dopant incorporated into two sets of thin films was estimated to be 0.8 and 8.5 at.%, by means of energy dispersive spectroscopy. On the basis of x-ray diffraction method, the type of crystalline structure and crystallites size were evaluated directly after the deposition process and after additional post-process annealing at 800 °C temperature. The influence of annealing on the surface properties was evaluated with the aid of atomic force microscopy. Uniformity of the dopant distribution in titanium dioxide matrix was examined with the aid of secondary ion mass spectroscopy. Additionally, using atomic force microscope, diversification and roughness of the surface was determined. Chemical bonds energy at the surface of TiO2:Nd thin films was investigated by x-ray photoelectron spectroscopy method. Wettability measurements were performed to determine contact angles, critical surface tensions and surface free energy of prepared coatings. On the basis of performed investigations it was found, that both factors, the amount of neodymium dopant and the post-process annealing, fundamentally influenced the physicochemical properties of prepared thin films.

Abstract

Titanium dioxide thin films were prepared using two types of magnetron sputtering processes: conventional and with modulated plasma. The films were deposited on SiO2 and Si substrates. X-ray diffraction measurements of prepared coatings revealed that the films prepared using both methods were nanocrystalline. However, the coatings deposited using conventional magnetron sputtering had anatase structure, while application of sputtering with modulated plasma made possible to obtain films with rutile phase. Investigations performed with the aid of scanning electron microscope showed significant difference in the surface morphology as well as the microstructure at the thin film cross-sections. The mechanical properties of the obtained coatings were determined on the basis of nanoindentation and abrasion resistance tests. The hardness was much higher for the films with the rutile structure, while the scratch resistance was similar in both cases. Optical properties were evaluated on the basis of transmittance measurements and showed that both coatings were well transparent in a visible wavelength range. Refractive index and extinction coefficient were higher for TiO2 with rutile structure.