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The objective of the study was to verify the hypothesis that GEN (genistein - phytoestrogen and an inhibitor of tyrosine protein kinase - TPK) effects on pig oocyte maturation and cumular cell expansion under in vitro conditions are connected with its estrogenic activity. Oocytes were cultivated for 24 hours up to the stage of the first meiotic metaphase (MI). Three different doses of GEN (13, 40, 80 µg/ml of medium) and also three doses of GIN, genistin, an analogue of GEN without effects on TPK, (80, 160 and 240 µg/ml of medium) were tested. To verify the reversibility of GEN effects, the oocytes were first cultivated for 24 hours with 80 µg of GEN per 1 ml of medium and then for another 24 hours without any GEN. GEN blocked pig oocyte maturation at the stage of the germinal vesicle (GV), depending on the dose. After rinsing out the GEN the oocyte maturation recovered, but with abnormalities (32%). GIN in a concentration of 80 µg/ml of medium induced a significant blockage at the GV stage (18%). With an increase in the GIN concentration, the number of oocytes blocked at the GV stage significantly decreased, but the abnormal maturation increased (up to 31%). GEN inhibited the cumular cell expansion in proportion to its dose. GIN had a less pronounced effect. As GEN and GIN effects demonstrate similar patterns, it is probable that estrogenic activity is involved.

The aim of the study was to evaluate the growth rate and selected carcass and meat quality parameters in bulls fed a high-grain diet and to compare the results with those obtained in bulls fed a diet based on preserved roughage. The trial included 18 Czech-Pied bulls fed a diet with a high proportion of concentrated feed and 18 Czech-Pied bulls fed a diet based on maize silage, used as a control group. The trial was launched after the weaning of calves. During the fattening period, live weight and average daily weight gain were monitored. The bulls were slaughtered at the live weight of 550-600 kg, the mean age at slaughter was 473 days for the high-grain diet group and 474 days for the control group. The carcasses were classified to SEUROP quality grades, and carcass gain and dressing percentage were calculated. Samples of m. longissimus pars thoracis were taken from five bulls in each group to examine selected meat quality parameters. In the period from weaning to slaughter the high-grain diet bulls and the control bulls achieved the average daily weight gain of 1.29 kg and 1.21 kg, respectively. Differences between the groups were not significant. The high-grain diet group showed higher average carcass weight and higher carcass weight gain, differences between the groups were not significant, either. As to meat quality parameters under study, a significant difference was found only in meat lightness (L*), with the mean value in the high-grain diet group being significantly (P ≤ 0.01) lower than in the control group. The other meat quality parameters did not show any significant differences between the groups. In this study, the high-grain diet gave similar performance as the maize silage-based diet in fattening bulls. The high-grain diet group and control group showed comparable average daily weight gain and selected carcass and meat quality parameters.

The frequent presence of rye translocation 1B/1R in common wheat is well known as well as its unfavourable effect on bread-making quality. These translocated materials make up more than one tenth of all wheat varieties registered in the Czech Republic and due to their lower technological value they are predominately used for livestock feeding in spite of the lack of information about their desirability for monogastric animals. Our study was aimed at a general effect of 1B/1R translocation, including other grain characteristics in model feeding tests with laboratory rats. Triennial evaluation of selected chemical and technological characteristics of winter wheat grain, including feeding characteristics in the model set of 18 DH lines with/without 1B/1R translocation, confirmed a highly significant effect of year on evaluated parameters. Wheat lines with the presence of 1B/1R translocation showed a significantly higher value of relative viscosity, crude protein content and higher proportion of the albumin + globulin fraction. This was manifested negatively in the technological characteristics of the gluten index (GI) and the Zeleny sedimentation test of these wheat lines. Detected values of relative viscosity, grain hardness (PSI) and albumin-globulin fraction were significantly influenced by the genotype of the wheat line. The relationships of evaluated grain characteristics to the results of feeding test were not unequivocal. The presence of 1B/1R translocation significantly decreased the values of balance in these characters: net protein utilization (NPU) and biological value of proteins (BV), however the effect of the 1B/1R translocation on protein efficiency ratio (PER) was not confirmed. Correlation analyses showed low mutual relationships among the parameters of balance and growth tests. A lower but significant positive correlation of the albumin + globulin fraction and a negative correlation of storage proteins with growth parameter PER were also observed. It is possible to summarize that individual relation between albumins + globulins and gluten protein composition of grains influenced the values of PER more significantly than the presence of 1B/1R translocation.

Carp pituitary proteins and glycoproteins were separated by the combination of immobilized metal affinity chromatography (IMAC) and affinity chromatography on Con A-Sepharose. The protein fractions were analysed by SDS-PAGE. Luteinizing hormone (in the α₁β and α₂β forms), growth hormone, free α₁ subunit and β subunit of thyroid-stimulating hormone were identified by N-terminal amino acid sequencing. N-linked oligosaccharide chains of thyroid-stimulating hormone (β TSH) were separated after fluorescent labelling on a GlycoSep N column and treated by exoglycosidases. Among the saccharide components, complex and hybrid structures terminating SO₄-GalNAc-GlcNAc-Man-, and high mannose structures, with 1 to 8 mannose units attached to the oligosaccharide core (GlcNAc)₂(Man)₃, were found.

Three groups of Brown fattened young bulls were studied, comparing the effects of rearing method (suckled vs. bucket reared) and of slaughter weight (400 vs. 480 kg). Suckled animals had higher fatness scores (2.2 vs. 1.3), more dissectible fat (14.5 vs. 9.1%), and higher intramuscular fat content (7.8 vs. 4.6%DM), accompanied by better scores in sensory tenderness (5.2 vs. 3.8) than did the bucket-reared ones. Animals slaughtered at a heavier weight showed a higher dressing percentage (57.5 vs. 53.8%), conformation score (9.2 vs. 6.2), and fat content (fatness score, dissectible fat and intramuscular fat). The meat from animals in the heavier group had lower a* (12.4 vs. 14.2) and higher b* (10.8 vs. 12.9) indexes, as well as higher scores in most sensory traits than the lighter ones.

This experiment investigated the effect of olive cake in the feed of weaned Pramenka lambs on their daily gain, carcass traits and on the chemical composition of different groups of muscles. For that purpose, 45 male lambs were divided into three groups with 15 lambs each and fed separately for 50 days. The first group (control) was fed a commercial concentrate, while the second and third (test) groups were fed a concentrate with the addition of 15% and 30% olive cake, respectively. The results showed that the high level of olive cake inclusion (30%) decreased (P < 0.01) daily gain, final weight, empty carcass weight and (P < 0.05) dressing percentage of lambs. The olive cake resulted in a significantly higher (P < 0.01) proportion of stomach and intestines in the carcass compared to the control. The content of fat, proteins and dry matter in all the analyzed groups of muscles was lowest in the carcasses of lambs fed olive cake. The results of this research suggest that the addition of 15% of olive cake to the concentrate had no significant negative effect on daily gain, carcass weight and dressing percentage of lambs.

Sows were dried off by a traditional method (control - C, restricted feeding before, during and after weaning) or by a modified one (experimental - E, intensive feeding before, during and after weaning). On day 5-6 after weaning of the 3

Experiments were conducted on calves divided into three groups, 6 animals in each, to determine the influence of the intake of non-acidified and acidified milk replacer on the level of acid-base homeostasis in venous blood. The milk replacer was supplied at a dose of 700 g dry matter in 8 l of the liquid in two feedings. The milk replacer was acidified by adding formic acid to ensure the concentration of 0.2% in milk replacer. Venous blood was collected before feeding and 1, 2, 4, and 6 hours after feeding. The samples were analyzed for blood pH, actual bicarbonate HCO₃^- (mmol/l), base excess BE (mmol/l), partial pressure of carbon dioxide pCO₂ (kPa) and partial pressure of oxygen pO₂ (kPa). Significant changes were observed in calves fed acidified milk of albumin type. The mean daily values of acid-base parameters in these calves were significantly lower in comparison with animals fed non-acidified milk replacer and reached the following levels: pH 7.343 ± 0.032 (P < 0.05), HCO₃ 24.49 ± 2.13 mmol/l (P < 0.01), BE 1.11 ± 1.97 mmol/l (P < 0.001). A similar tendency but of a more pronounced decrease in values was recorded in the group of calves fed acidified milk replacer of casein type: pH 7.312 ± 0.022 (P < 0.01), HCO₃^- 21.73 ± 0.75 mmol/l (P < 0.001), BE 96 ± 0.86 mmol/l (P < 0.001). In relation to the time after feeding the group of calves fed non-acidified milk replacer showed a rising tendency in the level of metabolic components (HCO₃^-), compensated by respiratory regulating mechanisms (rise in pCO₂) conducive to the maintenance of optimum blood pH level. The group of calves fed acidified milk replacer (formic acid 2 ml/l) of the albumin type showed metabolic acidosis with subsequent gradual adjustment and compensation by means of metabolic (HCOHCO₃^-) rather than respiratory regulation mechanisms. The calves fed acidified casein type milk replacer displayed metabolic acidosis with insufficient metabolic regulation and more intensive respiratory compensation (decrease in pCO₂). Concurrent investigations of the abomasum acidity and blood acid-base homeostasis reflected the joint action of both the acidifying effect of formic acid and significantly lower production of bicarbonate (HCO₃^-) related to the intake of acidified milk and the tendency to the development of metabolic acidosis.

The aim of this study was to investigate milk flow patterns and milk composition in relation to pre-milking udder stimulation. The milk of one quarter of each of the sixteen cows was removed separately and in the course of milking it was divided into six fractions (P cisternal milk during milking without stimulation and the first 300 ml during milking with pre-stimulation, 0-25%, 25-50%, 50-75%, 75-100%, 75-100%, MS-machine stripping) and into five portions (25%, 50%, 75%, 100%, 100% + MS). Two milkings were performed during two consecutive evening milkings with or without manual stimulation. Pre-stimulation resulted in a reduction of milking time, duration of the increase and decline phase of milk flow, stripping yield, but it increased the peak flow rate as compared to milking without pre-stimulation (P < 0.05). In both fractions and portions the content of fat increased steadily during milking and reached a maximum at MS. Lactose increased from P to 50-75% and then it decreased to MS. Significantly higher fat contents at 25% and 50% portions and in both protein and dry matter at 25% portions were found during milking with pre-stimulation as compared to no stimulation (P < 0.05). The content of fat, protein and dry matter were also higher in both P and 0-25% fractions for milking with pre-stimulation (P < 0.05). Pre-stimulation positively influenced the parameters of milk flow and therefore the efficiency of milk removal and contributed to better distribution of components in milk fractions during milking.

The study was conducted in a dairy barn and nearby environment to determine the level of air bacterial and fungi contamination. Measurements were performed in morning, noon and evening sampling periods once a week during two autumn months inside the barn and in a 25 m distant barn environment. A Merck MAS-100 air sampler was employed with different medium and incubation combinations for the capture and identification of bacteria and fungi. The results of the study showed a statistically significant difference (P < 0.05) between the bacterial and fungi counts measured inside and outside the barn, whereby total outside bacterial count was by 97.4% to 98.0% lower, and total outside fungi count by 85.2% to 99.4% lower than the respective indoor counts in various sampling periods. In 125 analyzed colonies, gram-positive bacteria, especially those of the genus Staphylococcus and Streptococcus, were most commonly identified in the air samples from both inside and outside the barn. Gram-negative bacteria were present at a low rate, predominated by enterobacteria and by the genus Moraxella and Pseudomonas. Nine mould genera were identified in 325 fungi colonies, predominated by the genus Aspergillus, Penicillium, Rhizopus and yeasts, both in the barn and in the nearby environment.

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.

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).

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.

The object of an experiment was inorganic and organic forms of zinc, copper and manganese applied in mineral mixtures to dairy cows. The experiment was carried out on 90 cows with average milk yield for previous lactation of about 9 500 kg milk. The cows received mineral mixtures containing inorganic or organic forms of zinc, copper and manganese for 6 weeks before calving and during the first three months of lactation. The application of microelements as bioplexes in amounts covering 30% of daily requirements of cows had a positive effect on an increase in colostrum dry matter content from 20.9 to 23.35% as well as on the concentration of protein and fat, and the level of minerals - calcium, phosphorus, magnesium, zinc and copper. In cows' milk in the 2^nd and 3^rd month of lactation there were no differences in contents of minerals. However in the blood serum of cows in the 1^st and 2^nd month of lactation an increase in calcium concentration from 1.96 to 2.14 g/kg was observed while the content of phosphorus also increased average from 1.76 to 2.22 g/kg in the first trimester of lactation.

In an experiment with 18 lactating Chios ewes, the replacement of barley grain, wheat grain, sugar beet pulp and lucerne meal with fermented olive wastes (FOW), maize grain and soybean meal was used to formulate diets that allowed the net energy (NE) for lactation (NE_l) density of FOW to be calculated. In the experiment, which lasted 8 weeks, ewes were allocated, after equal distribution for milk yield, body weight (BW) and lactation number, into three treatments of 6 ewes each in a Youden square experimental design with 4 consecutive periods of 14 days. Ewes in all groups were offered a concentrate mixture ad libitum (1.12 kg/ewe/day, dry matter (DM) basis) and lucerne hay (0.90 kg/ewe/day, DM basis). FOW were added to the concentrate mixture at inclusion levels (on an as-fed basis) of 0, 100 and 200 kg/t for treatments FOW0, FOW100 and FOW200, respectively. There were no differences among groups in milk protein (60.0 g/kg), lactose (53.0 g/kg) or ash (9.6 g/kg) contents, but milk fat content increased linearly (P < 0.01) with increasing dietary levels of FOW. Average milk yield (1 137 g/day) and yields of components tended (P < 0.10) to decrease with increased FOW feeding. The best estimate of the NEl density of FOW was 2.55 MJ/kg DM at 2.7×M NE intake, a value only slightly lower than that of 2.62 at 2.7×M based upon a Van Soest et al. (1984) discount from equations of Van Es (1978), who suggested 3.00 MJ/kg DM at 1.1×M of NE intake. FOW is a low protein, high fibre and low NEl feedstuff that will be of limited value in rations of high producing lactating ewes.

The objective of this paper was to assess by means of pedometers the period of anoestrus in a herd where the calving interval was 400 days and to detect the influence of some factors (breed, year, season, parity) on the length of anoestrus and the intensity of increased physical activity during oestrus. It was also monitored whether the intensity of increased physical activity would influence the conception rate. The observations were performed in a herd of 243 cows, 80 of them Czech Pied cows (C) and 163 of themHolstein cows (H) during 4 years. The cows were housed together in a free cubicle housing system. The cows of H breed produced 3 790 kg and those of C breed 3 087 kg of milk on average during the first 100 days of lactation. The mean calving interval was 400 days, and the mean number of services per pregnancy was 2.1. The cows were fed a total mixed ration. This ration has a low energy content (NEL) and excessive content of crude protein according to the official evaluation used in theCzechRepublic. The intake of NEL ensured the production of 30.9 l of milk and the intake of crude protein in 45 l of milk in these cows. The cows of both breeds significantly differed in the length of postpartal anoestrus, which is probably related to the negative energetic balance of H cows. The effect of parity, year of calving, and season of calving on the length of postpartum anoestrus was not demonstrated as statistically significant. A comparison of the walking activity over the oestrus period in the individual breeds demonstrated that the cows of the Czech Pied breed exhibited significantly higher activity. The highest walking activity was observed in first-calvers of both breeds, and the lowest walking activity during oestrus was recorded in winter. The cows with higher walking activity had a higher conception rate than those with lower walking activity.

The quality of produced milk and piglet growth were investigated in three groups of lactating Large White sows fed three mixtures containing different levels of lysine, threonine and crude protein. Piglets were weighed immediately after delivery and then in weekly intervals. At the age of 21 days the litter weight was the highest in group B (67.96 kg; P < 0.05), i.e. in the group with the highest dietary content of amino acids. Milk from lactating sows was sampled and analysed. An increased level of dietary amino acids became evident in milk at the first milk sampling (i.e. three days after delivery), when the content of lysine and threonine in milk was significantly the highest in group B (lysine 11.96 g/16 g N; threonine 6.72 g/16 g N; P < 0.05). The level of amino acids in milk and the differences between groups diminished in the following samplings. The changes of crude protein in milk were similar.

Ultraweak photon emission measurements were found to be a useful tool for investigating the influence of stress factors on cells. In the present study, induced photon emission of boar spermatozoa was investigated using a luminometer during a 12-day storage at 15°C in Biosolwens extender. It was shown that the day of storage had a significant effect on some photon emission parameters. During storage, a significant increase in the Integral, Peak max. and Slope max. parameters and a decline in the T.-half (fall) parameter were observed. A significant correlation was observed between photon emission parameters and sperm motility. In conclusion, the results of the present study indicate that the measurement of induced photon emission can be an alternative, sensitive and relatively simple method for assessing the effect of preservation on oxidative damage to boar spermatozoa.

In vitro study of the rumen fluid (RF) and hindgut content (HC) fermentation by microbiota taken from sheep grazing in an area atmospherically polluted from the non-ferrous metal industry was conducted and compared with controls from an uncontaminated area (UA). The experimental sheep were exposed to the prolonged intake of heavy metals by grazing in the contaminated area (CA) for one year. Soil and grass from that area and the rumen content of sheep were analyzed for heavy metal levels. Based on the levels of mercury (4.752 mg/kg), copper (232.9 mg/kg), cadmium (1.167 mg/kg), lead (92.509 mg/kg) and arsenic (74.59 mg/kg) the soil was categorized as profusely contaminated. Meadow hay (MH) from UA was used as a tested substrate of fermentation activity; it was incubated with buffered RF and HC inocula from CA and UA for 24 h. The gas volume in CA was significantly decreased by 50 and 36% in RF and HC, respectively. The methane production in CA was significantly decreased by 77 and 71% in RF and HC, respectively. The significantly decreased values of the fermentation parameters in CA in comparison with UA were accompanied by the reduced (P < 0.01) total concentration of rumen ciliate protozoa.

Twenty-four Czech dairy farms were visited to record lameness prevalence and to identify factors associated with high lameness prevalence at the farm level and/or increased lameness risk at the level of individual cows. All cows were checked for lameness and forty cows per farm were examined for overgrown claws, body dirtiness and skin lesions. The farm environment was scored between 1 (excellent) to 5 (very poor) in three different aspects: floor slipperiness, cow care quality, and housing quality. Data on hoof trimming schedules were obtained from farm managers. Lameness prevalence on farms was in a wide range from 6% to 42% (median 22%). At the farm level, floor slipperiness and poor animal care were associated with high lameness prevalence (Spearman correlations, P < 0.05), and the proportion of cows with overgrown claws tended to be associated with it (P < 0.10). The reported time schedules of hoof trimming (continuous trimming applied or not; and time elapsed since the whole herd was trimmed) were unrelated to either the prevalence of overgrown claws or the prevalence of lameness. Within farms, cows with overgrown claws and dirty cows were at an increased risk of being lame (multiple logistic regression, P < 0.05) and cows with skin lesions tended to be more lame (P < 0.10). The risk of lameness had an inverted U-shape dependence on age (P < 0.05), with cows at 7-8 years of age being the most endangered by lameness. We conclude that there is a large potential for lameness reduction on some Czech dairy farms through improving the cow care and reducing floor slipperiness, and that within farms, cows with overgrown claws and also dirty cows and cows with skin lesions should be given special attention since they are more likely to get lame.

At present the laying hen rearing is transformed into alternative housing systems which include a deep litter system. As for the poultry nutrition, the replacement of animal protein with vegetable protein in poultry feed is applied. Therefore, in an experiment we evaluated the quality of eggs from laying hens in the cage system as compared to the deep litter system with vegetable protein substituted for animal protein in their feed. 72 ISA Brown laying hens were placed into the experiment. 36 laying hens were kept in the deep litter system and 36 laying hens were kept in conventional cages for laying hens. For the period of 9 months, 36 eggs from the group in the deep litter system were examined, always at intervals of five weeks (i.e. 8 × 36 eggs) and so were 36 eggs from the group in the cage system (i.e. 8 × 36 eggs). We found out that in the deep litter system the mean egg weight was higher (P < 0.01), shell weight was lower (P < 0.01), egg albumen was higher (P < 0.01), yolk weight did not differ (P > 0.05), yolk cholesterol was higher (P < 0.01), yolk colour was darker (P < 0.05), shell strength did not differ (P > 0.05), all in comparison with the cage system of laying hen keeping. The results of the experiment show that where vegetable protein was substituted for animal protein in the nutrition of laying hens, there were differences in the quality of eggs from laying hens kept in the deep litter system and eggs from laying hens kept in the cage system.

Live body measurements of weight, height, length, girth, stifle- and hip-width and a measure of muscularity (ratio of stifle to hip width) were monitored on 258 Yankasa sheep stratified into age categories of 1 to over 3 years determined mostly from records and partly by dentition. These animals are from purebred Yankasa sheep kept as a part of the open nucleus-breeding scheme of the National Animal Production Research Institute, Shika, Zaria, Nigeria. The effect of sex, type of birth and age group of lambs on live measurements and muscularity were analyzed by least-squares procedures. All variables examined, except sex, had significant (P < 0.001) effects on all body measurements. At birth, male and single-born lambs were significantly heavier than female and twin-born lambs. At early age, most factors significantly (P < 0.01) influenced the body weight, body dimensions and muscularity traits with single-born lambs being 31% heavier, 10% taller and 11% bigger in girth; more highly muscled than the twin-born lambs. This advantage of male over female born lambs (except in hip-width and girth) for growth and developmental traits was maintained reasonably well to the advanced ages. All phenotypic correlations between body measurements were positive and significant (P < 0.001). The highest correlation coefficient was found between chest girth and body weight. The polynomial equation using chest girth as an independent variable predicted body weight more accurately as compared to the linear equation.

This research was carried out to determine the effect of Jerusalem artichoke (JA) with or without 5, 10% vetch (V) supplementation on performance, egg quality characteristics and egg cholesterol content. In the study, seventy-five 25 weeks-old commercial white laying hens were randomly divided into one control and 4 treatment groups each containing 15 hens. Control group was fed basal diet without JA or V. Treatment group 1, 2, 3 and 4 were fed diets containing 5% V, 5% JA, 5% JA + 5% V and 10% JA + 10% V, respectively. The feeding period lasted 16 weeks. In the study, it was determined that dried-ground JA contained dry matter, crude protein, ether extract, crude fibre, crude ash, inulin and metabolizable energy (ME) at the level of 93.30, 10.02, 0.36, 5.64, 9.05, 15.80% and 3 060 kcal/kg, respectively. At the end of the study, live weight was lower by 4.36-10.09% in the treatment group 10% JA + 10% V compared with the other groups, but feed efficiency was improved in this group. There were statistically significant differences between the groups in egg quality characteristics (P < 0.05, P < 0.001). Egg production was not affected by supplementation of 5, 10% JA with or without 5, 10% V supplementation. Egg yolk cholesterol and total cholesterol content were not different in the groups (P > 0.05). As a result, the addition of JA with or without V has no adverse effect on performance and egg quality in hens.

In this study the change in amino acid profile in cow's colostrum and transient milk during the first week after parturition was examined in a Hungarian Charolais herd. Experiments were carried out with n = 37 Charolais cows in the same herd in the spring (March-April) of two consecutive years (Experiment 1: 2002, n = 15; and Experiment 2: 2003, n = 22). Colostrum and milk samples were taken by hand milking immediately after delivery, and in 24, 48, 72, and 168 hours post partum. Amino acid contents (%) in samples were measured in milk protein with an automatic amino acid analyser. Data were processed by the software of SPSS.10 statistical program package. In the postpartal period, among essential amino acids significant increases were recorded in methionine, isoleucine, lysine, and phenylalanine, and among non-essential amino acids glutamic acid and proline increased significantly. Simultaneous decreases were recorded in valine, cysteine, aspartic acid, serine, glycine, and arginine. Inconsistent figures were determined for histidine, leucine, tyrosine, and alanine content between Experiment 1 and Experiment 2.

The aim of this study was to determine the effect of electric pulses on the structural and functional condition of rabbit oocytes. The New Zealand White female rabbits at 3-5 months of age and at 3-4 kg body weight served as oocyte donors. Oocytes after flushing from the oviducts were placed between two electrodes in an electroporation chamber which was filled with a dielectric solution. Following a short incubation in B2 medium, oocytes were subjected to an electric pulse released by an electrical pulse generator. Oocytes were then incubated in 500 µl of B2 medium supplemented with 20% foetal calf serum (FCS) at 38°C in an atmosphere of 5% CO₂ in air. Oocytes were cultured until the morula/blastocyst stage (approx. 72 h). The experiment was conducted using 430 oocytes obtained post mortem. In vitro cultured oocytes not subjected to an electric pulse were the control. Each group was subdivided into replications according to electric current intensity. The analysis of experimental variants shows that in the first variant all embryos developed to the morula stage but only 10% of them continued to develop to the blastocyst stage. In the second variant we observed that 5-10% of oocytes developed to the blastocyst stage after treatment with 2.0 and 2.5 kV/cm pulse but in the group of 1.0 kV/cm pulse 35% of oocytes developed only to the 2-12 b stage. In the third variant only 1 oocyte (5%) continued to develop to the blastocyst stage, but in the fourth variant oocyte development stopped at the morula stage. In the fifth variant, called an "extreme" one, oocytes stopped to develop at the stage of 2-12 b (about 25%) and the percentage of degenerated oocytes dramatically increased (about 60%).

The effect of dietary supplementation of selenium in an organic form on performance, carcass traits and selenium content in tissues of broiler cockerels Ross 308 was studied. The soya-wheat-maize diet contained 50 mg vitamin E/kg. The experiment was conducted on 810 straight-run broiler cockerels randomly divided into 3 groups: group I - control, without selenium supplement; experimental group: II - 0.3 mg Se/kg, Se-enriched yeast was applied as a Se source; III - 0.3 mg Se/kg, Se-enriched alga Chlorella as a Se source. The broiler chickens were slaughtered at 42 days of age. In performance traits higher (P ≤ 0.05) live weight of broiler chickens was recorded in the experimental groups (II - 2 430.6 g and III - 2 425.2 g). There were no significant differences between the groups in feed conversion and mortality. Se-enriched alga had the best feed conversion, and selenium supplementation slightly increased mortality in both experimental groups. No significant differences between the groups were found out in carcass traits and dressing percentage. The content of selenium in breast and thigh muscle, feathers and excrements increased (P ≤ 0.05) in both experimental groups compared to the control group. Higher values in breast and thigh muscle and in feathers were measured in the group supplemented with selenium from Se-enriched yeast, also in comparison with the group supplemented with selenium from Se-enriched alga Chlorella. The broiler chickens receiving Chlorella had a higher (P ≤ 0.05) selenium content in excrements compared to the group with Se-enriched yeast. The selenium concentration in liver was higher (P ≤ 0.05) in both experimental groups compared to the control. The supplement of selenium from Se-yeast and Chlorella in the diet for broiler chickens increased the microelement concentration in muscle.

The aim was to determine the conversion of alimentary substances of laying hens (nitrogen, phosphorus, potassium) into the production of eggs and to determine the emission of nitrogen, air pollution by dust and microorganisms in accordance with different technologies of layer rearing. The studies were conducted in 6 poultry houses. The birds were kept in premises in cage batteries BKN-3, "Spech", OBN-1, OBN-3 or on littered floor. It was found out that there was 1.6 times more dust in the air of poultry house where laying hens were kept on litter and the total number of bacteria was 2.4 times higher than in the bird cages (P < 0.001). The laying hens assimilated 21.95-28.42% of nitrogen, 19.63-31.25% of phosphorus, 6.04-8.33% of potassium for egg production and weight gains when feed is balanced. If cage technologies are applied, over a year, there is a loss of 6.7 ± 1.4% of nitrogen through the excrements because of nitrogen emission. When the technologies of littered floor are used, there is a loss of 18.5 ± 4.8% of nitrogen extricated with the excrements (P < 0.025). When the birds were kept in cages, 0.059 ± 0.011 kg of nitrogen per each bird evaporated because of ammonia emission, while in the case of littered floor - 0.227 ± 0.126 kg of nitrogen.

The objective of the experiment was to evaluate the effect of starter diet containing 10% of treated rape cake (TRC) with a reduced glucosinolate content on calf growth, development and health. The experiment included 45 calves allocated into 3 groups. After the colostrum period (5 days) the calves were fed 4 l of pooled fresh milk per calf/day and one of the starters ad libitum. The control group (S) was fed Standard starter with components with a standard nutrient content including fibre. Comparative group T was fed Telstar starter, which contained whole maize kernels and protein pellets. Experimental group G was fed Grant starter containing 10% of treated rape cake. The calves were fed hay ad libitum from 10 weeks of age. The average starter consumption (calf/day) over a 90-day feeding period was 1.34, 1.72 and 1.45 kg of the Standard, Telstar and Grant diet, respectively. An insignificantly higher body weight of calves was recorded for the Grant group at the end of the experimental period. When the calculated indices were compared, it was obvious that the weight gains obtained with experimental starters Grant and comparative Telstar were by 4.0% higher and by 5.4% lower, respectively, than in the control group Standard. No significant changes in the parameters of nitrogen, energy, lipid and mineral metabolism, health status, hepatic parenchyma and thyroid function were observed throughout the experimental period. The diet based on experimental starter Grant had no adverse effect on the ruminal fermentation in calves. It may therefore be concluded that the starter diet with 10% content of treated rape cake had no adverse effect on calf growth and performance.

Two experiments were conducted to investigate the effects of dietary crude protein level and degradability on milk urea nitrogen (MUN) content. In experiment 1, twelve multiparous lactating cows averaging 176 days in milk were divided according to DIM and milk production into three 4 × 4 Latin squares with four 2-week periods. Cows were fed four diets with different crude protein levels (13.0, 14.0, 15.0, and 16.0%, DM basis) with isocaloric, respectively. Crude protein levels had a low effect on milk yield and composition (P > 0.05), but a significant effect on MUN content. There were significant differences in the MUN content of cows fed either of the two diets (P < 0.01). In experiment 2, fifteen multiparous Holstein dairy cows averaging 91 days in milk were classified according to DIM and milk production into five 3 × 3 Latin squares with three 3-week periods. Cows were fed one of the three isocaloric and isonitrogenous diets with RUP being 30.8%, 36.2%, and 41.6% (CP basis), respectively. Milk yield, milk composition, and MUN content were not significantly affected by protein degradability, and there were no significant differences between any two dietary treatments (P > 0.05). These results indicated that MUN might be used as a parameter to monitor the change in dietary protein levels.

A total of 36 samples of feed - 19 samples of hays and 17 samples of silages were used for estimation of in vivo and in vitro digestibility. The organic matter digestibility (OMD) was estimated by in vivo and two in vitro techniques (method of Tilley and Terry and two-stage pepsin-cellulase method (Pepcel)). The regression equations were calculated from the results obtained in the experiment. Tilley and Terry method provided consistent results of OMD estimation for both the groups of roughages: in vivo OMD = 14.7 + 0.782 × [Tilley and Terry] (n = 18; R² = 0.76); in vivo OMD = 36.3 + 0.513 × [Tilley and Terry] (n = 16; R² = 0.75) for hays and silages, respectively. Different accuracy was found out in Pepcel method: in vivo OMD = 37.0 + 0.478 × [Pepcel] (n = 19; R² = 0.49); in vivo OMD = 37.8 + 0.484 × [Pepcel] (n = 17; R² = 0.87) for hays and silages, respectively.