Template-Type: ReDIF-Article 1.0 Author-Name: J. Petr Author-Workplace-Name: Institute of Animal Science, Prague-Uhříněves, Czech Republic Author-Workplace-Name: Department of Veterinary Sciences, Czech University of Life Sciences, Prague-Suchdol, Czech Republic Author-Name: E. Chmelíková Author-Workplace-Name: Department of Veterinary Sciences, Czech University of Life Sciences, Prague-Suchdol, Czech Republic Author-Name: L. Tůmová Author-Workplace-Name: Department of Veterinary Sciences, Czech University of Life Sciences, Prague-Suchdol, Czech Republic Author-Name: M. Ješeta Author-Workplace-Name: Department of Veterinary Sciences, Czech University of Life Sciences, Prague-Suchdol, Czech Republic Title: The role of nitric oxide in parthenogenetic activation of pig oocytes: A review Abstract: Parthenogenetic activation of mammalian oocytes with artificial stimuli is commonly applied in various reproductive biotechniques, e.g. cloning using nuclear transfer. For this reason, many studies focus on oocyte activation in vitro. Recently we have described the activation of pig oocytes using nitric oxide. This activating stimulus is very specific in many aspects. However, it does not provide an adequate stimulus for parthenogenetic development. It was shown that nitric oxide stimulated some signalling pathways which are inactive in conventional treatments for parthenogenetic activation, e.g. the cGMP-dependent signalling cascade. On the other hand, nitric oxide does not stimulate certain signalling pathways involved in oocyte activation after calcium ionophore, e.g. the PKC signalling cascade. The aim of this review is to characterize the complex processes induced in oocytes after treatment with nitric oxide. Perspectives for further research and the application of nitric oxide for parthenogenetic activation of oocytes are outlined. Keywords: oocyte, parthenogenesis, activation, nitric oxide Journal: Czech Journal of Animal Science Pages: 363-377 Volume: 52 Issue: 11 Year: 2007 DOI: 10.17221/2323-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/2323-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-200711-0001.txt Handle: RePEc:caa:jnlcjs:v:52:y:2007:i:11:id:2323-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: P. Homolka Author-Workplace-Name: Institute of Animal Science, Prague-Uhříněves, Czech Republic Author-Name: J. Harazim Author-Workplace-Name: Central Institute for Supervising and Testing in Agriculture, Opava, Czech Republic Author-Name: J. Třináctý Author-Workplace-Name: Research Institute for Animal Breeding, Ltd., Pohořelice, Czech Republic Title: Nitrogen degradability and intestinal digestibility of rumen undegraded protein in rapeseed, rapeseed meal and extracted rapeseed meal Abstract: In this study, nutritive values of rapeseed (R), rapeseed meal-expeller A (RM-A), rapeseed meal-expeller B (RM-B) and extracted rapeseed meal (ERM) were compared. The trials were performed using the in sacco method with three steers of the Czech Fleckvieh breed, which were fitted with a permanent ruminal cannula. Nylon bags with samples were incubated in the rumen for 2, 4, 8, 16, 24 and 48 hours. The effective degradability (ED) of crude protein (CP) was calculated at 0.08, 0.06 and 0.04 1/h of rumen particulate outflow rates (k), and the obtained ED values were 65.4, 70.8 and 77.4% for R, 86.7, 88.1 and 89.7% for RM-A, 82.2, 84.4 and 87.0% for RM-B and 56.3, 62.1 and 69.6% for ERM, respectively. The ED values significantly differed between feeds (P < 0.05) for all rumen particulate outflow rates. Disappearances of amino acids (AA) after 16 hours of incubation in the rumen of R, RM-A, RM-B and ERM were determined. In all cases, the concentrations of AA in the feeds determined after incubation in rumen were lower than in the original feeds. A mobile bag technique was used to determine intestinal digestibility. In the experiment, three dry cows fitted with permanent large ruminal cannula and the T-piece cannula in the proximal duodenum were used. The intestinal digestibilities of rumen undegraded CP (DSI) were estimated 30.0% in R, 15.4% in RM-A, 27.6% in RM-B and 65.3% in ERM. The DSI values significantly differ between the feeds (P < 0.05), except for the difference between R and RM-B. Keywords: rapeseed, rapeseed meal, extracted rapeseed meal, ruminant, protein, amino acids, degradability, intestinal digestibility Journal: Czech Journal of Animal Science Pages: 378-386 Volume: 52 Issue: 11 Year: 2007 DOI: 10.17221/2320-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/2320-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-200711-0002.txt Handle: RePEc:caa:jnlcjs:v:52:y:2007:i:11:id:2320-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: R. Cempírková Author-Workplace-Name: Faculty of Agriculture, University of South Bohemia, České Budějovice, Czech Republic Title: Contamination of cow's raw milk by psychrotrophic and mesophilic microflora in relation to selected factors Abstract: The objective of the paper was to analyse the influence of dairy cow management technology, milking method, predipping and summer grazing on the contamination of cow's raw milk by mesophilic (TBC), psychrotrophic (PBC), lipolytic (PLiBC) and proteolytic (PPrBC) bacteria. The values of TBC, PBC, PLiBC and PPrBC in bulk milk samples were determined by the culture method according to IDF standards. Investigations were carried out in nine stables of seven dairy farms from January 2005 to June 2006. Summer grazing has the most marked influence on the values of studied parameters. Farms with summer grazing had a lower microbial contamination of milk compared to farms without grazing and the difference was statistically highly significant in all studied parameters (P < 0.001). A positive effect of predipping on a reduction in the values of milk microbial contamination was proved while the difference between farms with predipping and those without it was on a significance leve lP < 0.05 to 0.001 except PLiBC. A comparison of the influence of dairy cow management technology indicated the lowest values of all microbiological indicators in loose cubicle littered housing, higher values were determined in stanchion littered housing and the highest in loose slatted-floor housing. A statistical difference between the technologies was proved mainly in TBC (P < 0.001). Farms with milking in milking parlours had a lower microbial contamination of milk compared to farms that used the in-stall milking pipeline system but the difference was statistically significant only in TBC (P < 0.05). Keywords: milk, total bacterial count, psychrotrophic bacteria count, lipolytic bacteria count, proteolytic bacteria count, management technology, predipping, grazing Journal: Czech Journal of Animal Science Pages: 387-393 Volume: 52 Issue: 11 Year: 2007 DOI: 10.17221/2325-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/2325-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-200711-0003.txt Handle: RePEc:caa:jnlcjs:v:52:y:2007:i:11:id:2325-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: B. Janštová Author-Workplace-Name: Department of Milk Hygiene and Technology, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic Author-Name: M. Dračková Author-Workplace-Name: Department of Milk Hygiene and Technology, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic Author-Name: P. Navrátilová Author-Workplace-Name: Department of Milk Hygiene and Technology, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic Author-Name: L. Hadra Author-Workplace-Name: Department of Milk Hygiene and Technology, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic Author-Name: L. Vorlová Author-Workplace-Name: Department of Milk Hygiene and Technology, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic Title: Freezing point of raw and heat-treated goat milk Abstract: The freezing point (FP) was established in 48 bulk tank samples of raw and 48 samples of pasteurized goat milk that were collected in the course of lactation. Alongside, non-fat solids (NFS) content was monitored. Milk freezing point measurements were carried out using the thermistor cryoscope method in compliance with the standard CTS 570538 (1998). The mean freezing point of raw milk was found to be in an interval of -0.5513 ± 0.0046°C, variation ranged from -0.5466°C to -0.5567°C, with higher values in the spring months and a drop at the end of lactation. FP corresponded to the NFS content. The average freezing point of goat milk heat-treated on the farm to the temperature of 72°C over a period of 20 s was -0.5488 ± 0.0046°C, pasteurisation brought an average increase in FP by 0.0025°C. Keywords: cryoscopy, milk, goats, pasteurization, freezing point Journal: Czech Journal of Animal Science Pages: 394-398 Volume: 52 Issue: 11 Year: 2007 DOI: 10.17221/2324-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/2324-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-200711-0004.txt Handle: RePEc:caa:jnlcjs:v:52:y:2007:i:11:id:2324-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: Z. Váradyová Author-Workplace-Name: Institute of Animal Physiology, Slovak Academy of Sciences, Košice, Slovak Republic Author-Name: S. Kišidayová Author-Workplace-Name: Institute of Animal Physiology, Slovak Academy of Sciences, Košice, Slovak Republic Author-Name: P. Siroka Author-Workplace-Name: Institute of Animal Physiology, Slovak Academy of Sciences, Košice, Slovak Republic Author-Name: D. Jalč Author-Workplace-Name: Institute of Animal Physiology, Slovak Academy of Sciences, Košice, Slovak Republic Title: Fatty acid profiles of rumen fluid from sheep fed diets supplemented with various oils and effect on the rumen ciliate population Abstract: The profile of trans-fatty acids and the protozoan population were evaluated in four ruminally fistulated sheep fed a diet with meadow hay: barley grain ratio (80:20%) plus sunflower oil (SO), rapeseed oil (RO) or linseed oil (LO) (5% wt/wt). The concentrate was daily mixed with individual oils and offered at 07.00 h. A 4 × 4 Latin square with 4-week periods was used. The concentration of trans-vaccenic acid (TVA) was the highest 4 h after feeding (36.1 g/100 g FA with SO; 34.5 g/100 g FA with RO) and then decreased with the time after feeding (P < 0.05). The concentration of cis9, trans11 conjugated linoleic acid (c9,t11-CLA) with RO increased from 3.23 g/100 g FA (2 h after feeding) to 4.67 g/100 g FA (4 h after feeding). The concentration of c9,t11-CLA with SO increased from 2.09 g/100 g FA (2 h after feeding) to 2.31 g/100 g FA (4 h after feeding). The concentration of c9,t11-CLA with LO was the highest 4 h after feeding (2.07 g/100 g FA). Overall effects of the oil supplements and time after feeding on short-chain fatty acids (SCFA), medium-chain fatty acids (MCFA) and long-chain fatty acids (LCFA) in the rumen fluid were evident. A strong interaction of oil supplements and time after feeding was detected in the concentration of UFA and SFA (P < 0.001). A significant effect of LO on the rumen ciliate population was observed; the total protozoan concentration and the number of Entodinium spp. were decreased as well as Dasytricha ruminantium, Isotricha spp., Polyplastron multivesiculatum, Ophryoscolex c. tricoronatus and Eremoplastron dilobum. Keywords: sunflower oil, rapeseed oil, linseed oil, fatty acids, rumen ciliates Journal: Czech Journal of Animal Science Pages: 399-406 Volume: 52 Issue: 11 Year: 2007 DOI: 10.17221/2322-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/2322-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-200711-0005.txt Handle: RePEc:caa:jnlcjs:v:52:y:2007:i:11:id:2322-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: J.H. Yao Author-Workplace-Name: College of Animal Science and Technology, Northwest A and F University, Yangling, Shaanxi, China Author-Name: J.C. Han Author-Workplace-Name: College of Animal Science and Technology, Northwest A and F University, Yangling, Shaanxi, China Author-Name: S.Y. WU Author-Workplace-Name: College of Animal Science and Technology, Northwest A and F University, Yangling, Shaanxi, China Author-Name: M. XU Author-Workplace-Name: College of Animal Science and Technology, Northwest A and F University, Yangling, Shaanxi, China Author-Name: L.L. Zhong Author-Workplace-Name: College of Animal Science and Technology, Northwest A and F University, Yangling, Shaanxi, China Author-Name: Y.R. Liu Author-Workplace-Name: Shenzhen Kondarl (Gaoling) Feed Co., Ltd., Gaoling, Shaanxi, China Author-Name: Y.J. Wang Author-Workplace-Name: Shenzhen Kondarl (Gaoling) Feed Co., Ltd., Gaoling, Shaanxi, China Title: Supplemental wheat bran and microbial phytase could replace inorganic phosphorus in laying hen diets Abstract: An experiment was conducted to determine effects of wheat bran (WB) phytase on production performance and nutrient utilization in laying hens. Three hundred and seventy-five Lohmann hens at 32 weeks of age were randomly allotted to treatments of fifteen hens per pen with five pens per treatment. Five experimental diets were formulated. Diet one (control) contained 0.19% inorganic phosphate (Pi) from dicalcium phosphate. On the basis of diet 1, diet 2 and 3 were formulated to contain WB 5% and 10%, respectively. In diet 4 and 5, the WB was fixed at the level of 10% with Pi level adjusted to 0.14% in diet 4 and completely replaced with 500 U/kg microbial phytase in diet 5. The results showed that treatment three improved egg yield (P = 0.142), feed conversion ratio (FCR) (P = 0.011), utilization of crude protein (CP) (P = 0.060) and total phosphorus (tP) (P < 0.001), and serum Pi concentration (P = 0.016) compared with the control. Ten percent of WB replacing 0.05% Pi did not influence either egg yield or nutrient utilization. Compared with the control, treatment five improved FCR (P = 0.011) and utilization of CP (P = 0.060) and tP (P < 0.001), but did not influence either performance or serum parameters. The current study suggests that wheat bran could be used successfully in laying hen diets and wheat bran and microbial phytase supplemented together could replace inorganic phosphate completely. Keywords: wheat bran phytase, laying hens, production performance, nutrient utilization Journal: Czech Journal of Animal Science Pages: 407-413 Volume: 52 Issue: 11 Year: 2007 DOI: 10.17221/2321-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/2321-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-200711-0006.txt Handle: RePEc:caa:jnlcjs:v:52:y:2007:i:11:id:2321-CJAS