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Optimal dietary concentrations of vitamin C and chromium picolinate for alleviating the effect of low ambient temperature (6.2 degrees C) on egg production, some egg characteristics, and nutrient digestibility in laying hensOriginal PaperN. Sahin, K. SahinVet Med - Czech, 2001, 46(9):229-236 | DOI: 10.17221/7887-VETMED This experiment was conducted to evaluate the effect of vitamin C (L-ascorbic acid) and chromium (chromium picolinate, Cr Pic) on egg production, some egg characteristics, and digestibility of nutrients in laying hens (Hy-Line) reared under a low ambient temperature (6.2°C). Two hundred and ten laying hens (32 week-old) were divided into seven groups, 30 hens per group. The treatment groups were designed in a 2 × 3 factorial arrangement using two levels of vitamin C (125 and 250 mg/kg of diet) and three levels of chromium picolinate (200, 400, or 800 µg/kg of diet), and control group was fed basal diet. The highest values of performance were obtained if 250 mg/kg vitamin C was supplemented with either 400 or 800 µg Cr per kg of diet. An interaction between vitamin C and chromium for egg production (P = 0.05) and feed efficiency (P = 0.02) was detected. Similarly, egg weight, specific gravity, egg shell thickness, egg shell weight and Haugh unit improved with diet containing 250 mg vitamin C and either 400 or 800 µg Cr per kg of diet (P £ 0.05). Digestibility of dry matter (DM), ash, organic matter (OM), crude protein (CP), and ether extract (EE) were higher with higher dietary vitamin C (P £ 0.05) and also with higher Cr (P £ 0.05). There were no interactions between vitamin C and chromium detected for any parameters measured for egg quality in terms of egg weight, specific gravidity, egg shell thickness, egg shell weight and Haugh unit and digestibility of nutrients (P 3 0.28). Data obtained in the present study shows that a combination of 250 mg vitamin C and 400 µg chromium per kg of diet gave the best results in laying hens reared under a low ambient temperature and a conclusion is suggested that such a diet can be considered as a protective management practice in poultry to alleviate, at least in part, the depressive effect of cold stress on poultry performance. |
Evidence of spice black pepper adulterationB. TremlováCzech J. Food Sci., 2001, 19(6):235-239 | DOI: 10.17221/6613-CJFS The goal of this work was to verify the spice adulteration by the microscopic analysis. The samples of black powdered pepper and its meat product that did not have the expected spice and aromatic properties were controlled. The results of sensory and chemical investigation corresponded with microscopic findings. The suspected sample of spice and meat product with spice contained pronounced coloured parts that were not present in the usual structure of powdered pepper. |
Variations in contamination by mercury, cadmium and lead on swine farms in the district of Hodonin in 1994 to 1999Original PaperR. Ulrich, J. Raszyk, A. NápravníkVet Med - Czech, 2001, 46(5):132-139 | DOI: 10.17221/7872-VETMED Environmental samples (n = 254) were collected at regular intervals from 1994 to 1999 on three swine farms in the area of the district town Hodonín, Czech Republic. The samples of feed mixtures (n = 85), barn dust sediments (n = 44), and muscular (n = 42), hepatic (n = 41), and renal (n = 42) tissues of feeder pigs were analysed for the concentrations of mercury, cadmium and lead. The concentrations of mercury showed decreasing tendencies in animal tissue samples (1994-1996). Compared with the mean for the Czech Republic, the concentration of mercury was markedly higher in liver and kidney samples (0.064 mg/kg and 0.114 mg/kg, respectively) collected in 1998, the concentration of cadmium was moderately higher in feed, muscle, liver, and kidney samples collected in 1996-1998. Statutory limits were exceeded in two liver and two kidney samples and one feed sample only. The concentration of lead in muscle, kidney, and feed samples (1994-1996) and barn dust samples (1996-1998) showed also a decreasing tendency. However, the limit was exceeded in 16 muscle samples (0.11 to 0.23 mg/kg) collected in 1994-1999 and two kidney samples collected in 1996 (0.74 mg/kg) and 1999 (0.77 mg/kg). Heavy metals present in dust sediments apparently did not contribute significantly to their content in animal tissue. While the health risk resulting from the contents of mercury and cadmium can be classified as moderate, the contents of lead must be regarded as markedly more dangerous. |
Wheat and flour quality relations in a commercial millM. Hruąková, K. Hanzlíková, P. VaráčekCzech J. Food Sci., 2001, 19(5):189-195 | DOI: 10.17221/6606-CJFS The bread-making quality of forty commercial winter wheat samples, grown in the western region of the CzechRepublic, and their flours (white flours with ash content of about 0.5%) prepared in a commercial mill was studied. Standard analytical methods (ash and protein content, wet gluten), amylolytic activity measurement (falling number), rheological investigation (alveograph, gluten index), sedimentation test and laboratory baking test were used for characterization of wheats and flours. In addition NIR method was used to calculate ash, wet gluten, sedimentation value and protein content. Statistically significant correlations were found practically between all tested quality parameters of wheat and corresponding flour samples. However, the strongest correlation (r = 0.69-0.70) significant at 0.01 level exists between specific bread volume and protein and wet gluten content, determined both by standard or by NIR methods. |
Find of bird-pox (variola avium) in blackcap (Sylvia atricapilla)Original PaperJ. Rajchard, V. RachačVet Med - Czech, 2001, 46(3):78-79 | DOI: 10.17221/7858-VETMED In August 1999 there were netted and ringed passerines in the Naděje fishpond system in Třeboň area. 14 individuals of blackcap (Sylvia atricapilla) of both sexes and various age were caught. All individuals of this species had expressive pathological changes on feet. Histological investigations proved bird-pox (variola avium). No symptoms of this disease were found in other caught 11 species. |
Determination of astringent taste in model solutions and in beveragesH. Valentová, S. ©krovánková, Z. Panovská, J. PokornýCzech J. Food Sci., 2001, 19(5):196-200 | DOI: 10.17221/6607-CJFS The astringent taste is important for the sensory quality of beverages. Perception thresholds of two important astringent compounds - tannic acid and (+)-catechin were determined using two procedures. The concentration-intensity dependence was linear at low concentrations and up to medium intensities of the astringent taste if unstructured graphical scales were used, but the saturation threshold was soon attained in the case of tannic acid. Recording the results on printed forms gave similar results as using a touch-sensitive monitor. The optimum tasting was achieved at swallowing after degustation of 5 s. The duration of degustation increased the intensity. The astringent flavour was suppressed by sugar, but was not significantly influenced by ethanol, citric acid or quinine hydrochloride. Astringent substances were accurately perceived and rated in wine, tea infusion and orange drink, but the increase of astringency was smaller than in model solutions. The astringent taste was easily distinguished from the bitter taste. |
Determination of essential oils content and composition in caraway (Carum carvi L.)J. Sedláková, B. Kocourková, V. KubáňCzech J. Food Sci., 2001, 19(1):31-36 | DOI: 10.17221/6571-CJFS Total content and composition of essential oils in caraway seed (Carum carvi L.) from a selection of caraway varieties grown in different production areas were determined after supercritical fluid extraction (SFE) and steam distillation. Different procedures of sample pretreatment (homogenization) and methods of isolation were compared from the point of view of efficiency, reproducibility and accuracy. The effect of storage period was also examined. |
The use of the computer technology for the evaluation of the strict morphological sperm analysisOriginal PaperZ. Věľník, O. Matouąková, D. ©vecová, A. ZajícováVet Med - Czech, 2001, 46(2):35-40 | DOI: 10.17221/7849-VETMED A programme for evaluating the strict morphological analysis of sperm was developed. The programme was verified by conducting 552 morphological analyses of bull, stallion, boar and human ejaculates. The method was evaluated by comparing the results obtained by routinely used morphological examinations with the results received by the automatic method SASMO. The following advantages of the programme were demonstrated: it is possible to obtain information on the proportion of normal and pathological spermatozoa, to determine the frequency of the respective characteristics analysed, to express detected alterations per pathological spermatozoon (teratosperm index), to express frequency of respective alterations per total number of spermatozoa examined, to display alterations according to their frequency and differentiate between developmental and acquired alterations. It was proved that using the detailed morphological evaluation of sperm by the survival test, it is possible to get statistically significant information on the prediction of sperm survival. The programme represents an important aid for making the morphological evaluation of sperm quality more objective both in veterinary and human medicine and in all insemination stations and assisted reproduction centres. |
Serosurvey of sheep and goats to Chlamydia psittaci in Slovakia during the years 1996-2000Original PaperM. Trávniček, D. Kováčová, P. Zubrický, L. ČislákováVet Med - Czech, 2001, 46(11):281-285 | DOI: 10.17221/7895-VETMED In the Slovak Republic during the years 1996-2000, total 30 278 blood samples from sheep and 4 756 from goats were examined serologically by the method of a complement fixation. The IgG antibodies against Chlamydia psittaci in sheep and goats according to individual years were as follows: 1996 - 6.37% sheep/3.94% goats, 1997 - 9.25%/10.02%, 1998 - 9.57%/2.96%, 1999 - 7.91%/3.69%, 2000 - 10.99%/6.08%, respectively. In most clinically healthy animals, the low levels of IgG antibodies in dilution of 1 : 16 to 1 : 32 were detected. In sheep during the years of 1996, 1998, 1999 and 2000 the high levels of IgG antibodies 1 : 256 to 1 : 1 024 were caught unambiguously testify to the chlamydial abortion in sheep. In goats, the high titres were caught in 1997 and 2000 - 1 : 256 to 1 : 512, also confirm the chlamydial aetiology of the infectious process. |
Iodine concentrations in porcine blood, urine, and tissues after a single dose of iodised oilOriginal PaperI. Herzig, B. Písaříková, I. Diblíková, P. SuchýVet Med - Czech, 2001, 46(6):153-159 | DOI: 10.17221/7875-VETMED Experimental groups of pigs were treated orally with 120 mg (Group O 120), or 480 mg (Group O 480) of iodine per animal, or intramuscularly with 240 mg (Group I 240) of iodine per animal. Iodine was administered in the form of iodised fatty acid esters (IFAE). The treatment resulted in significantly increased iodine concentrations in tissues and a single dose was sufficient to meet the requirement for the whole fattening period (180 days). Urinary iodine concentrations in all the experimental groups were higher than in the control group C receiving iodine only from conventional feed. Urinary excretion of iodine between days 2 and 5 was more distinctive in orally treated than in intramuscularly treated animals (Figure 1). Iodine concentrations at the end of the fattening period (day 180) were higher in the treated than in the control groups. The treatment effect was more marked in Groups O 480 and I 240 than in Group O 120. The dynamics of blood serum iodine concentrations was similar to urinary concentrations (Figure 2). Mean thyroid gland weights in the groups O 120, O 480, I 240, and C were 9.19, 8.51, 7.10, and 12.01 g, respectively. An opposite tendency was observed for iodine concentrations in thyroid gland dry matter (Figure 3). No effects of any of the treatments on total protein, albumin, total lipids, or cholesterol concentrations in blood serum were observed. Group C showed lower tissue iodine concentrations than any of the experimental groups. The only exception was hepatic tissue in which approximately the same iodine concentrations were found in all the groups. Data obtained in Groups O 120, O 480, and I 240 indicate that decisive for tissue concentrations was rather the dose of iodine than the route of administration. Iodine is stored above all in the thyroid gland and adipose tissue. As can be seen in Figure 4, its concentration was higher in muscles with a higher proportion of fat (neck) than in lean muscles (ham). |
Bionomics of Acarus siro L. (Acarina: Acaridae) on oilseedsOriginal PaperRadek Fejt, Eva ®ďárkováPlant Protect. Sci., 2001, 37(3):111-114 | DOI: 10.17221/8373-PPS The bionomics of Acarus siro was studied at 18 and 20°C and 70 and 80% R.H. on wheat germs, linseed, rapeseed and sunflowers to obtain data for optimisation of biological control of stored product mites on oilseeds. Wheat germs were used as a control substrate as they were considered optimal for development of A. siro. The development of eggs and larvae was longer than that of protonymphs and tritonymphs. Wheat germs appeared to be a better substrate for the development of mites than oilseeds. Generally, the life span of females as well as the oviposition period was shortest on wheat germs while longest on sunflower; also, at the higher temperature the female life span was shorter. The maximum number of eggs laid by a single female (356) was recorded on wheat germs at 20°C and 80% R.H. The development was significantly shorter at 20°C than at 18°C regardless of humidity. There were no significant differences between the effects of the tested oilseeds. |
Content of phenolic acids in rye caryopses determined using DAD-HPLC methodR. Amarowicz, S. WeidnerCzech J. Food Sci., 2001, 19(6):201-205 | DOI: 10.17221/6608-CJFS Phenolic compounds were extracted from rye caryopses with 80% (v/v) methanol. Phenolic acids were determined as free compounds and those liberated from soluble esters and glycosides. The analyses were performed using a Waters HPLC system equipped with a diode array detector (DAD). The following free phenolic acids were found: p-coumaric, ferulic and sinapic; the phenolic acids liberated from soluble esters were as follows: vanillic, caffeic, p-coumaric, ferulic and sinapic; and those liberated from soluble glycosides were the following: vanillic, p-coumaric, ferulic and sinapic. In rye caryopses, phenolic acids were chiefly in the form of soluble esters. A diode array detector was especially useful for the determination of vanillic acid: the UV spectrum of this compound showed a maximum at 260 nm whereas UV spectra of other phenolic acids were characterised by maxima at longer wavelengths. |
