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The observation was carried out in a group of 70 female cattle in the course of two years. The animals were kept in suckler herds. They were provided with pasture grass and maize silage indoors during the grazing season and with forage ration (silage and hay) in winter. The aim of the study was to assess the effect of year (2001 and 2002), season (spring and autumn), breed (Aberdeen Angus AA, Beef Simmental BS, Blonde d'Aquitaine BA, Charolais CH, Hereford HE and Limousin LI) and reproduction cycle (pregnant heifers PH, non-pregnant heifers NPH, pregnant cows PC, non-pregnant cows NC and lactating cows with calves LCC) on some blood plasma parameters. Mean values of these parameters were following: Total protein 72.37 gl⁻¹ , glucose (Glu) 3.23 mmol∙l⁻¹, urea (Urea) 4.39 mmol∙l⁻¹, bilirubin (Bilir) 4.63 mmol∙l⁻¹, alkaline phosphatase (ALP) 1.02 µkat∙l⁻¹, asparate aminotransferase (AST) 1.29 µkat∙l⁻¹, gamma glutamyltransferase (GMT) 0.30 µkat∙l⁻¹, sodium (Na) 114.33 mmol∙l⁻¹, calcium (Ca) 2.30 mmol∙l⁻¹ and phosphorus (P) 1.99 mmolT1. Year affected TP, Glu, Bilir, ALP, AST (all p<0.01) and urea (p<0.05). Season affected TP, Glu, urea, Bilir, Ca, P (all p<0.01) . There were significant differences in urea, GMT, Ca and P between breeds. Reproduction cycle affected TP and Glu (p<0.05). It can be concluded that year and season affected the observed blood plasma parameters considerably more than breed or reproduction cycle.
The pharmacokinetics of flunixin meglumine was determined after its multiple (altogether 4 doses at 24-hours intervals) intravenous administration at a dose of 2.2 mg/kg body weight in six mature clinically healthy heifers. Plasma flunixin and its metabolite 5-hydroxyflunixin concentrations were analyzed with high-pressure liquid chromatography using an assay with a lower limit detection of 0.03 μg/ml for both substances. Plasma concentrations versus time curves were described by a two compartment open model. Mean plasma flunixin concentrations were similar on day 1 and 4, and than rapidly decreased (within 2 hours) from initial concentrations higher than 10 μg/ml to the concentrations lower than 1 μg/ml. The distribution phase of flunixin was short (t05α = 0.29 ± 0.16 and 0.18 ± 0.04 on day 1 and 4, respectively) and the elimination phase was more prolonged (t05ß = 3.30 + 0.60 and 3.26 + 0.22 on day 1 and 4, respectively). The mean residence time of flunixin was similar on day 1 (1.83 ± 0.83) and 4 (1.88 + 0.46), and for 5-hydroxyflunixin this parameter was insignificantly (P > 0.05) higher on day 1 (5.49 ± 2.22) as compared to that found on day 4 (3.99 ± 2.17). The clearance of flunixin was similar on both examined days (0.23 ± 0.12 on day 1 and 0.31 ± 0.15 on day 4), and for 5-hydroxyflunixin was insignificantly (P > 0.05) lower on day 1 (2.37 ± 1.21) as compared to that determined on day 4 (3.23 ± 1.06). Our data indicate that multiple administration of flunixin did not alter significantly the parent drug and its metabolite concentrations in plasma, however may cause some small changes in pharmacokinetic parameters.
The objective of the study was to determine beef production traits of dairy and dairy × beef breed crossbred heifers. The data from Finnish slaughterhouses included observations of 14 221 Nordic Red (NR), 6 348 Holstein-Friesian (Hol), 1 626 NR × Aberdeen Angus (NR × Ab), 1 136 NR × Blonde d’Aquitaine (NR × Ba), 802 NR × Charolais (NR × Ch), 487 NR × Hereford (NR × Hf), 3 699 NR × Limousin (NR × Li), 827 NR × Simmental (NR × Si), 531 Hol × Ab, 467 Hol × Ba, 438 Hol × Ch, 186 Hol × Hf, 1 249 Hol × Li and 393 Hol × Si heifers. Crossbreeding with late maturing beef breeds (Ba, Ch, Li, Si) had favourable effects both on daily carcass gain and carcass quality traits (conformation, proportion of high value joints) of the progeny when compared to purebred dairy heifers. No advantages in proportion of high value joints seemed to be obtained by crossbreeding dairy cows with Ab or Hf breeds, while the improvements in daily carcass gain and carcass conformation score were intermediate compared to the late maturing crossbreds.
Leaving on ovaries a morphologically dominant follicle on the day of start of superovulation significantly lowered its effectiveness in heifers. Mechanical removal of the dominant follicle increased the effectiveness of superovulation. Influence of elimination of a dominant follicle was especially visible in these cases, in which the follicle remained on the ovary during 4 d before the programme started. Significant differences were ascertained in the numbers of corpora lutea found on ovaries on the day of embryo collection and in the numbers of nonfertilized ova.
The studies were done on 30 heifers with synchronized oestrus. IFN-γ was found in sera of 4 heifers in luteal phase and in 1 heifer in follicular phase. Moreover, an increased level of serum haptoglobulin (Hp) and serum amyloid component (SAA) was found in 8 heifers in follicular phase. The presence of IFN-γ a proinflammatory cytokine may point to an active inflammation, whereas an increased level of Hp and SAA in oestrus could be connected with an approaching ovulation. It was also found that in pregnant heifers with a detected IFN-γ and TNF-α and an increased level of Hp and SAA retention of placenta and post parturient metritis was diagnosed.
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.
The aim of this study was to detect heifers with dystocia using artificial neural networks (ANN). A total of 531 calving records of Holstein-Friesian heifers of Black-and-White strain and 8 diagnostic variables were used. The output variable was the class of calving difficulty: difficult or easy. Perceptrons with one (MLP1) and two (MLP2) hidden layers and radial basis function (RBF) networks were investigated. The root mean square error and the structure of selected ANN (number of neurons in the input, hidden and output layers) were 0.22, 10-4-1; 0.25, 10-17-17-1 and 0.19, 10-25-1 for MLP1, MLP2 and RBF, respectively. The percentage of correctly recognized heifers with difficult and easy calvings and that of correctly diagnosed heifers from both categories for the training and validation sets were approx. 90%. The same values for the test set were 75-83%, 82–88% and 82–86%, respectively. In both cases, no significant differences in these proportions were found. The following variables contributed most to the detection of heifers with dystocia: gestation length, BCS index, CYP19-PvuII and ERα-BglI genotypes and percentage of HF genes in heifer’s genotype.
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