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Blood samples were taken from 134 Holstein cows between day 20 to 100 postpartum to determine the concentration of urea, cholesterol, glucose and total lipids and to define their relation to the reproductive performance traits: interval (I), service period (SP) and insemination index (II). Investigations were carried out in monthly intervals from October 1996 to October 1997. Average values of plasma urea, total lipids, cholesterol and glucose for the entire period studied were 5.78 mmol.1⁻¹, 3.61 g.l⁻¹, 3.34 mmol. l⁻¹ and 3.61 mmol. l⁻¹, respectively. High concentration of blood urea was related negatively with the value of the insemination index (rp = -0.51). When the average concentrations of total lipids were low in plasma in the specified time (month) negative correlations were found between total lipids and the length of service period (rp = from -0.23 to -0.54) and value of the insemination index (rp = -0.42). The concentration of plasma total lipids increased in time from post partum. Traits of reproductive performance were affected by the internal environment. Especially negative influences were observed when the concentration of plasma urea as well as total lipids and cholesterol increased or decreased abnormally.
Bovine leukocyte adhesion deficiency (BLAD) and citrullinemia are two autosomal recessive genetic diseases in Holstein cattle and both result in death of homozygous animals. Through the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technology and DNA sequencing, one citrullinemia and three BLAD carriers were found in a population of 615 Chinese Holstein cattle, including 436 cows and 179 bulls. Citrullinemia and BLAD carrier frequency was 0.16% and 0.49%, respectively, in tested Chinese Holstein cattle. In this study, the first citrullinemia carrier occurring in Chinese Holstein cattle is described, although the world frequency of this disorder is very low.
The aim of this study was to investigate the relationship between the loss in body condition score (BCS) and loss (ΔBCS), energy balance (EB), hepatic lipidosis and blood serum concentration of non esterified fatty acids (NEFA), glucose, triacylglycerol (TAG) and total bilirubin (tBIL) in healthy dairy cows during transition period. Twenty healthy Holstein cows were included and categorized into groups based on BCS loss (ΔBCS) between dry period and early lactation (ΔBCS <0.75 and ≥0.75). Significant differences between groups (p<0.05) were observed for blood serum NEFA, glucose and tBIL. Cows with high ΔBCS (≥0.75) between dry period and early lactation showed increased blood serum NEFA, TAG and tBIL concentrations and lower blood serum glucose concentration during transition period, compared to the low ΔBCS cows (<0.75). Metabolic profiles of cows during transition period indicate high level of lipid mobilization from adipose tissue, possible decreased liver cells TAG export and gluconeogenic ability and impaired bilirubin metabolism if ΔBCS is increased by more than 0.75 points. ΔBCS was in relation with energy balance (EB) in transition period.
The purpose of this study was to evaluate the effects of ketoprofen (KTP), flunixin meglumine (FLM), and meloxicam (MLX) administration on acute-phase proteins after dehorning in Holstein heifers. A total of 21 Holstein heifers were enrolled into three groups of equal size (n=7) and administered ketoprofen, flunixin meglumine, or meloxicam, at doses of 2.2 mg/kg, 1.1 mg/kg, and 1 mg/kg body weight, respectively. Serum amyloid A, haptoglobin, and ceruloplasmin levels were determined before the administration of the three drugs (0 hrs) and at 6, 12, 24, 48, and 96 hours post-administration. The mean values (±SD) obtained revealed no significant alteration in APP levels at 0 hrs in any of the three groups. Time-dependent alterations, however, were significant in all groups. Group-time interactions were significant (P < 0.001) for ceruloplasmin concentrations, whereas results for serum amyloid A and haptoglobin levels were deemed non-significant. Inter-group interaction revealed no significant findings regarding serum amyloid A and ceruloplasmin levels, but haptoglobin levels showed a significant difference between the KTP and FLM groups at 48 hrs. It may therefore be reasonably suggested that KTP, FLM, and MLX could all be administered to effect slight changes in acute phase proteins.
Groups of 19 to 24 dairy Holstein cows were observed monthly for the period of 12 months (12 test days). The aim of the study was to observe the relationship between blood plasma cholesterol concentration and milk production and milk components. The mean milk yield was 33.8 kg with milk protein content 2.96%, milk fat content 4.02% and cholesterol concentration in blood plasma 3.44 mmol/1. Cows in the experimental groups were in their early lactation (on average 58.6 days after calving). The coefficients of the correlation between blood plasma cholesterol and some milk production parameters calculated for each test day ranged as follows: - 0.361 to 0.437 for milk yield, -0.275 to 0.203 for milk fat content and -0.181 to 0.480 for milk protein content. Polynomials of the third degree or higher were calculated for the observed parameters so as R~ was higher than 0.5. The calculated coefficients of correlation between blood plasma cholesterol content and milk production parameters did not reveal a clear tendency in the relationships. However, the graphical polynomial expression of relationships showed a positive relationship between blood plasma cholesterol content and milk yield and a negative relationship between blood plasma cholesterol and milk protein content. No relationship was found between blood plasma cholesterol concentration and milk fat content due to high variability of fat content in milk.
The purpose of this study was to determine the serological prevalence of bovine leukemia virus (BLV), and describe whether there are effects of BLV infection on the fertility of dairy cattle in Burdur, Turkey. The study population was 182 clinically healthy Holstein cows (>2-years-old) and 81 heifers (17- to 20-months-old) from a commercial dairy herd in Burdur. BLV prevalence was 66.48% (121/182) and 62.96% (51/81) in cows and heifers, respectively. There were no significant differences between BLV antibody-negative and antibody- -positive cows for days open (DO; P = 0.2567) or between BLV antibody-negative and antibody-positive heifers for first service age (FSA; P = 0.65). Moreover, differences in conception rates (CR) between BLV antibody-negative and antibody-positive cows or heifers were insignificant (P > 0.1). In conclusion, even though the prevalence of BLV infection in Burdur region was found to be high, no effect of BLV infection was detected for fertility.
The experimental group consisted of 57 young Holstein bulls kept in the Czech Republic; 35 bulls were tethered and 22 bulls were loose housed. The aim of the study was to analyse and compare the effect of different housing systems on feedlot performance, carcass value and meat quality and their mutual relationship. The overall average values were as follows: feedlot performance parameters live weight at slaughter 434.3 kg, age at slaughter 455.8 days, total weight gain 319.3 kg, duration of fattening 342.1 days, daily weight gain 941 g; carcass value parameters dressing percentage 51.0%, net daily weight gain 482 g, weight and proportion of kidney fat 3.9 kg, 1.8% resp., weight and proportion of fat trim 2.2 kg and 2.0% resp.; meat quality parameters dry matter, fat and collagen content in muscle 23.8, 1.46 and 1.13% resp., pH24 6.08, drip loss 0.849% and remission (525 nm) 6.4%.
The studies were carried out in the North -West part of Poland. The investigation was conducted on 292 specimens of the Holstein cattle with added 50% of HF.The extensity and intensity of the coccidia infection were determined by means of the Willis-Schlaaf's and McMaster's methods. Six species of coccidia were found : E. bovis, E. auburnensis, E. zürni, E. ellipsoidalis, E. subspherica and E. cylindrica. Twenty seven per cent of dairy cows and 49.6 per cent of calves were infected . Number of oocysts per gram of feces in calves ranged form 333 to 2237. Observations on the dynamics of the coccidia invasion in calves during a yearly cycle exhibited the existence of two peaks; a vernal and an autumnal ones.
Concentrations of serum sialic acid, malondialdehyde (MDA), retinol, zinc, and copper were measured in 52 lactating Holstein cows. Out of them, 15 were controls, 21 mildly lame, 7 moderate lame, and 9 severely lame. The animals were housed in free-stall barns with a slurry surface and were not released for pasture feeding. Compared to control animals, the mean serum total sialic acid concentrations in animals with severe lameness, but not in those with mild and moderate lameness, were increased significantly (P<0.01). The levels of MDA were higher in severely lame animals than in controls as well as in mildly and moderately lame animals and the differences were statistically significant (P<0.001). Contrary to the elevated serum concentrations of sialic acid and MDA in severely lame cows, the mean serum retinol value of these animals showed a remarkable decline (P<0.05). As for serum zinc and copper concentrations, there were statistically no significant alterations between the groups. In conclusion, results of the present study indicate that the concentrations of serum total sialic acid, MDA and retinol are associated with a degree of the lameness.
Bovine leukocyte adhesion deficiency (BLAD) is a well characterised lethal autosomal recessive disease that occurs in Holstein cattle. The discovery of this genetic disorder in 1990 by KEHRLI et al. was serendipitous and occurred in conjunction with studies of new methods to prevent mastitis in periparturient dairy cows ( KEHRLI et al. 1992a). In this review article we are attempting to summarise the last 6-year research (1990-1995) covering major aspects of BLAD syndrome, its worldwide prevalence with emphasize on current and future development on BLAD research.
Relations between the concentration of glucose and urea in blood plasma and the qualitative ejaculate parameters were investigated in 24 breeding bulls (13 Holstein and 11 Czech Spotted) over a 12-month period. The average concentrations of plasma glucose and urea were 3.32 mmol ∙ 1⁻¹ and 3.57 mmol ∙ 1⁻¹ , respectively. No statistically significant differences in the concentrations of glucose and urea (i.e. 3.34 vs. 3.30 mmol ∙ 1⁻¹ and 3.53 vs. 3.61 mmol ∙ 1⁻¹, respectively) were observed between the Holstein bulls and Czech Spotted bulls. A statistically significant (P ≤ 0.05) positive correlation was found between the concentration of plasma urea and the ejaculate volume for the whole investigation period (rp = 0.19). Similarly, the correlation between the concentration of plasma urea and sperm motility was positive (rp = 0.11), whereas the increase in plasma urea concentration negatively influenced sperm concentration ( rp = -0.10). Correlations between plasma glucose concentrations and the respective parameters of ejaculate quality were similar in magnitude, i.e. ejaculate volume ( rp = 0.12), sperm motility ( rp = 0.12) and sperm concentration ( rp = -0.08). During the investigations the coefficients of correlation between plasma glucose and urea concentrations as well as qualitative parameters of the ejaculate were found to be negative in months when concentrations of glucose and urea in the blood plasma of the bulls markedly changed.
This study was carried out on cattle to detect the seroprevalence of theileriosis and babesiosis around the Antakya province. A total of 214 randomly selected cattle were examined from selected locations for Theileria annulata, Babesia bigemina, B. bovis and B. divergens. Blood samples were collected from the cattle by jugular vene puncture to obtain sera for IFAT. Thin blood smears were prepared from the punctured ear veins of each animal. The blood smears were stained with 5% Giemsa's stain and examined microscopically at 100 × magnification. None of the Babesia species was detected but T. annulata observed in 5 (2.33%) blood smears. The sera were tested for the presence of antibodies to the T. annulata, Babesia bigemina, B. bovis and B. divergens by IFAT. Antibodies were detected against T. annulata in 24 and B. bigemina in 2 sera of the tested 214 cattle. Antibodies for B. bovis and B. divergens were not detected in any sera. It has been concluded that detailed molecular biological, serological and epidemiological studies needed to clarify the genetic and antigenic diversity of the blood parasites in Turkey.
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