Beáta Koréneková

The effect of cadmium in combination with zinc and selenium on ovarian structure in Japanese quails

In this study the effect of cadmium, cadmium+selenium and cadmium+zinc administration on the ovarian structure in Japanese quails was studied. The morphometric analysis of the relative volume of primary follicles detected the highest value in control group with a similar value in the group with administration of cadmium with selenium. Lower relative volume is reported in group with cadmium and zinc administration and the group with simple cadmium administration (P < 0.05). The relative volume of growing follicles was very similar in all studied groups (11.33–15.35%), and the relative volume of stroma was very stable (82.59–86.45%). In the evaluation of the number of follicles undergoing atresia detected significantly higher number of atretic primary follicles as well as atretic growing follicles in the group with cadmium administration and cadmium with selenium administration in comparison with control group. In comparison of normal and atretic follicles we report the most negative effect of single cadmium administration on ovarian structure. Selenium co-administration shows protective effects but only the co-administration with zinc prevent significant cadmium ovarian alterations.

Effects of vacuum packaging conditions on the quality, biochemical changes and the durability of ostrich meat

In this study, the effects of vacuum packaging conditions on the concentrations of lactic acid, malondialdehyde, pH, microbial and sensory analysis were determined during chilled storage of ostrich meat. Meat was packed as follows: vacuum packed from 1st day (VP-1), vacuum packed from 3rd day (VP-3) and non-vacuum packed (NVP). Analysis were performed at 1st, 7th, 14th, 21st day after slaughter. Meat consisted of 74.69% water, 2.29% fats, 20.95% proteins. Package conditions had significant effect on the pH (NVP: 6.54 on the 14th day, VP-1: 6.05 and VP-3: 6.07 on the 21th day p<0.001), amount of malondialdehyde (NVP: 8.62mg/kg on the 14th day; VP-1: 1.95 and VP-3: 2.55 on the 21th day; p<0.001) and total microbial count (NVP: 7.4 log CFU/g on the 14th day; VP-1: 6.7 and VP-3: 6.8 on the 21th day p<0.01). Based on these results we can assess that vacuum packed from 1st day is necessary for the 21 days storage of ostrich meat.

Post-mortem changes in the concentration of lactic acid, phosphates and pH in the muscles of wild rabbits (Oryctolagus cuniculus) according to the perimortal situation

In this study changes in the concentrations of lactate, phosphates, and pH values of water extracts of muscles of transported and hunted rabbits during ripening were determined. Concentrations of lactate were higher in the muscles of hunted rabbits. The highest differences were obtained 24h after kill/hunt. Concentrations of lactate in the muscles of hunted rabbits were decreasing, while in the muscles of transported rabbits we observed it to increase in the 7th day and then decrease in the 14th day. Higher concentrations of phosphates were found in the muscles of transported wild rabbits. During the ripening process concentrations of phosphates were decreasing in muscles of both groups. Muscles of hunted rabbits had lower pH values during the whole ripening process. Our research showed that concentrations of lactate, phosphates and pH value post-mortem depended on the perimortal situations.

Observation of the effects of nitrites and nitrates on yogurt culture

Abstract This work investigates the effects of nitrites and nitrates on yogurt culture. If the yogurt culture contained nitrites, titratable acidity was seen to decrease markedly. With nitrates, differences in titratable acidity could be observed (controls-11.25 g litre −1 lactic acid; maximum addition-9.58 g litre −1 lactic acid). At a standard addition of 100mg.kg −1 nitrites to milk containing a yogurt culture, the former (100mg.kg −1 nitrite) was reduced to a mean value of 69.02 mg.kg −1 NaNO 2 . In milk containing 100mg.kg −1 NaNO 3 and yogurt culture the resulting concentration was 84.30 mg.kg −1 NaNO 3 .

Concentrations of selected trace elements in organs and tissues of livestock from a polluted area

The occurrence of cadmium (Cd), nickel (Ni) and lead (Pb) from industrial emissions were determined in the muscle and liver of cattle from agricultural farms near an industrial plant in Eastern Slovakia. In this study cows (n = 25) were slaughtered and the concentrations of Cd, Ni, Pb were analyzed with a the atomic absorption spectrophotometer. Levels reaching the highest permissible hygiene limits for toxic metals Cd, Pb and Ni were determined in 50 samples. The maximum levels of Cd, Pb and Ni were recorded in the liver (0.865; 2.324; 1.140 mg/kg, respectively) and muscle (0.300; 0.854; 0.700 mg/kg, respectively). It was concluded that the exposure to an industrial plant significantly increases the levels of contaminants in the muscle and organs of cattle, as the most susceptible livestock.

Evaluation of some parameters of post mortem changes of pheasant (Phasianus colchicus)

Post mortem changes were evaluated in muscle tissues of 99 male, uneviscerated pheasants (Phasianus colchicus) stored for up to 14 days at 0 and 4 °C. The control group (Group I) included regularly slaughtered and bled pheasants (n=33). From approximately 350 pheasants hunted on a single occasion, specimens were taken and, on the basis of X-ray examination performed from latero-lateral and dorso-ventral body projection of hunted pheasants, two groups were constituted: Group II included pheasants (n=33) with one or multiple shots in the muscle tissues but not in the body cavity, whereas Group III included pheasants (n=33) with shots in both muscle tissues and the body cavity. Each group was divided into two subgroups, in which uneviscerated pheasants were stored at 0 °C and 4 °C, respectively, for a maximum of 14 days. Randomly selected pheasants from each subgroup (n=4), were examined on days 0, 3, 7, and 14. The following post mortem changes in breast and thigh muscles were evaluated: pH value (in watery extract), lactic acid and ammonia concentration. Generally, low pH values were associated with higher concentrations of lactic acid, most pronounced in breast muscle. Significant differences (P<0.05) in pH – both at 0 and 4 °C storage temperature – were found for breast muscles between Groups I and II, albeit average differences were merely in the range of merely 0.1 to 0.2 units. Thigh muscles of Group I had significantly lower pH (0.2 to 0.4 units) than Groups II and III, for all study days. A statistically significant difference (P<0.05) was found between the lactic acid concentrations in breast muscles (4 °C) between groups II and III. The highest average concentrations of ammonia in the breast muscle (day 14) were determined in the Group III (4 °C), and the lowest in the group of slaughtered pheasants (4 °C). The highest average concentrations of ammonia in the thigh muscles were in Group III (0 °C), and the lowest in the group of slaughtered pheasants (0 °C). This difference was statistically significant (P<0.05). In summary, muscles from pheasants being slaughtered instead of hunted were characterised by lower pH, higher lactic acid and lower ammonia concentration at the end of the storage period.

The effects of long-term cadmium exposure in turkeys: Accumulation and zinc prevention

Experiments with turkeys were conducted to determine the effects of long-term ingestion of Cd (2.0 mg Cd/day/turkey) on its accumulation in the tissues and organs. The cadmium was found especially in the muscles, livers and kidneys. The highest average content of cadmium was found in the kidneys (1.09 mg/kg). The contents of Cd in the kidneys and livers were 19 times and 14 times (respectively) higher compared to the muscles. The administration of Zn (72 mg / day / turkey) along with high doses of Cd, significantly (P < 0.001) reduced the concentrations of Cd in the organs of the experimental animals. The average concentrations of cadmium in the kidneys and livers of turkeys from the CdZn group were 43 % and 48 % (respectively) lower than the average concentrations in the same organs in the turkeys from the group which received only Cd.

Effect of feeding of prefermented bioproduct containing gamma-linolenic acid and beta-carotene on selected parameters of broiler chicken meat quality

The aim of the work was to evaluate the effect of addition of prefermented bioproduct with a increased content of polyunsaturated fatty acids (especially gamma-linolenic acid) and beta-carotene into commercial feed on the selected qualitative parameters. The chemical composition, the color, the loss of water, the pH and the concentration of lactic acid of the meat of broiler chickens (COBB 500) were monitored. Bioproduct was prepared from corn scrap, which was fermented using the lower filamentous fungus Umbelopsis isabellina CCF2412. The prepared material was mixed into the commercial compound feed intended for broiler chickens at a ratio of 10%, and was fed from the 11 th day of age of the chickens until the time of slaughter. The obtained results were compared with the results of control group, which was represented by broiler chickens fed only with a commercial compound feed. Feeding of bioproduct, in terms of chemical composition, affected mainly the fat content in breast and thigh meat, which was lower in the experimental group. Meat color (measured by colorimetric assay) was not affected and differences were significant only at a value a*, which was higher in the experimental group. Statistically significant differences in the water losses of meat were not recorded, but the feeding of bioproduct affected the pH of the meat, and also the concentration of lactic acid and both parameters were higher in the meat of control group.

Effect of quantum therapy on pork quality.

In this study the impact of quantum therapy on meat quality of slaughtered pigs was investigated. For this purpose the pigs were treated with different doses of magnet-infrared-laser (MIL) radiation. Animals were divided into four groups according to radiation doses (4096, 512, and 64 Hz, and control without application), which were applied in the lumbar area of musculus longissimus dorsi (loin) at various time intervals prior to the slaughter (14 d, 24 h, and 1 h). Animals were slaughtered and the meat quality was evaluated by determining of pH value (1, 3, and 24 h post slaughter), drip loss, colour, and lactic acid and phosphoric acid amounts. MIL therapy can be used in various fields of veterinary medicine as are surgery and orthopaedics, internal medicine, dentistry, pulmonology, gastroenterology, gynaecology, urology, nephrology, and dermatology. The results achieved showed that MIL radiation used in a short period before slaughter (1 h) can cause a change in the meat quality, as reflected by the non-standard development of pH values, increases in drip loss, and changes of meat colour.