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41.
A direct non‐parametric method was used to calculate reference (physiological) haematology values for farmed 10–12‐month rainbow trout of the Kamloops strain (mean weight: 330±131 g) with respect to red blood cell counts (RBCc), haematocrit values (Hct), haemoglobin concentrations (Hb), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentrations (MCHC). The fish in the selected reference group (n=798) were given dry pelleted diets that contained 37–47% crude protein, 7–18% crude fat and 108–300‐mg vitamin E, 1.08–5‐mg folic acid, 0.018–0.05‐mg vitamin B12, 48–64.5‐mg iron, 4.5–8.4‐mg copper and 0.18–0.24‐mg selenium supplied per kg of diet. Ethoxyquin and butylhydroxytoluol were used to protect the fat component against oxidation. The fish were kept at a stocking density of 50kg per cubic metre in tanks provided with running freshwater (dissolved oxygen 8.4–11.5 mg L?1, with O2 saturation of 77–98%) at an ambient temperature of 0.2–16°C. Blood was sampled between September and November at a photoperiod of 9–13 h:11–15 h (light:dark). Reference ranges for the preceding haematological indices were as follows in immature females (males): RBCc, 0.77–1.42T L?1 (T – tera, 1012) (0.98–1.55T L?1); Hct, 0.304–0.502 (0.34–0.546); Hb, 54–93 g L?1 (59–97 g L?1); MCV, 282–469 fL (279–434 fL); MCH, 51–86 pg (47–78 pg); MCHC, 0.15–0.22 (0.15–0.2). In males, values for RBCc, Hct and Hb were significantly higher (P=0.01 and 0.0000 respectively) and those for MCV, MCH and MCHC were significantly lower (P=0.01 and 0.0002 respectively) than in immature females. Nutritional and environmental factors affecting erythropoiesis in trout and some correlations between haematological (RBCc, Hb, Hct) and biochemical indices of the blood plasma (total protein, cholesterol) are discussed.  相似文献   
42.
Oxidation of rainbow trout haemoglobin (Hb) by nitrite proceeded via an initial lag phase followed by autocatalysis when the O2 saturation of the Hb was high. At low O2 saturations, the rate of methaemoglobin (metHb) formation was strongly reduced and autocatalysis was absent. Addition of adenosine triphosphate and guanosine triphosphate to oxyHb lowered the haemoglobin O2 affinity and O2 saturation and slowed down nitrite-induced metHb formation in a dose-dependent manner, the effect of GTP being larger than that of ATP. Reduced nicotinamide adenine dinucleotide (NADH) and the catecholamines adrenaline and noradrenaline did not affect O2 saturation in oxyHb solutions but significantly slowed down nitrite-induced metHb formation. Inorganic salts (NaCl, KCl, NaNO3) impeded the oxidation of oxyHb by nitrite in a manner that was dependent on salt concentration but independent of the type of salt. The mechanisms and physiological implication of the effects are discussed.  相似文献   
43.
Some teleost fishes exhibit a non-linear release of H+ with haemoglobin oxygen saturation (SO2) in whole blood that may be related to the Root effect and a low apparent cooperativity in oxygen binding. To further investigate this correlation, the relationship between red cell pH (pHi) and SO2 was evaluated in two teleost fishes, the carp (Cyprinus carpio) and tambaqui (Colossoma macropomum). Carp possess a relatively small Root effect within the physiological pH range, while that in tambaqui is relatively large. It was therefore hypothesized that both species would possess a non-linear release of H+ with SO2 under in vivo conditions, but that the degree of non-linearity would be less pronounced in carp than in tambaqui. Red cell suspensions of tambaqui showed a marked non-linear relationship between pHi and SO2 at in vivo pH values (pHe=7.66), where the majority of Bohr protons were released between 50 and 100% SO2. In whole blood of carp, the relationship between pHi and SO2 was almost linear at normal resting extracellular pH values (pHe=8.10) where Hills n 50 (cooperativity) was 1.3. Under acidic conditions (pHe=7.11), n 50 decreased to 0.9 and the release of H+ with SO2 became slightly non-linear. The reduction in pH in carp blood was associated with the onset of the Root effect, and the oxygen tension at half saturation (P50) increased from 3.8 to 38.2 mmHg. The relationship between total CO2 and SO2 in carp whole blood changed from being almost linear at pHe 8.1 to being non-linear at pHe 7.1, consistent with the relationship between pHi and SO2. Thus, possession of a Root effect could be a prerequisite for a non-linear release of Bohr protons with oxygenation, but the expression in whole blood may depend upon a species-specific cooperativity threshold. The non-linear release of Bohr protons with oxygenation may be a general phenomenon in teleosts with important implications for gas transport and acid-base homeostasis.  相似文献   
44.
Bitches with dystocia most often present with clinical signs of uterine inertia (UI). The aetiology of myometrial dysfunction in most of these cases is still not elucidated. We compared blood ionized calcium (iCa) and glucose concentrations in bitches diagnosed with primary UI (PUI, n = 14), secondary UI (SUI, n = 6) or obstructive dystocia (OD, n = 6), and we described their haematology profiles. Bitches diagnosed with UI had a patent birth canal and delivered no puppies yet (PUI) or only part of the whole litter (SUI). The OD group had no UI and showed strong abdominal contractions. Blood iCa did not differ between the PUI, SUI and OD groups and was not influenced by litter size. There was a significant positive relationship (R2 = .241, p = .013) between iCa concentrations and the dam's body weight. Glucose concentrations were also not significantly different between dystocia groups or influenced by body weight and litter size. Hypocalcaemia was detected in 11 bitches, and hypoglycaemia in two bitches. Pregnancy‐associated anaemia was seen in about one‐third of the bitches. Eight of 12 dogs had increased platelet counts, and ten had leukocytosis with mature neutrophilia. Although iCa did not differ between dystocia groups, low concentrations may have contributed to the development of UI in some of the small size bitches. Hypoglycaemia was uncommon, and therefore, we consider low glucose concentrations not to have played an important role in the pathogenesis of UI in our study population. Pregnancy‐associated anaemia, thrombocytosis, leukocytosis and mature neutrophilia were common findings in otherwise healthy bitches diagnosed with different forms of dystocia.  相似文献   
45.
Livestock blood discarded during slaughtering has potentially valuable components such as plasma proteins and haemoglobin. Plasma is used as a feed additive following processing via different methods, including spray drying, whereas blood cells have been underutilized. In this study, we developed haemoglobin hydrolysate (HH) and iron-enriched residue (IER) from porcine blood cells and investigated whether their oral administration regulates the immune system and gut microbiota in growing rats. Twenty-one Sprague-Dawley male rats (n = 7) were used during a 4-week trial and were fed a control, HH or IER diet. The ratio of beneficial bacteria such as Lactobacillus and Akkermansia strains increased in rats fed HH or IER diets. Moreover, compared with the control group, the IER group had an elevated ratio of Lactobacillus to Enterobacteria, which is regarded as an index of beneficial aspect in the gut. Phagocytosis of peripheral blood leucocytes was higher in the HH and IER groups than in the control group. The level of plasma immunoglobulin G increased to approximately 72.7 mg/ml and 152.0 mg/ml in the HH and IER groups, respectively, which was significantly (p < 0.05) higher than that in the control group. These results confirm that HH and IER developed in this study may be a potential additive for animal feeds.  相似文献   
46.
After electrophoresis on cellulose acetate, two haemoglobin phenotypes were detected in Baloochi and Kordi breeds: AA and AB phenotypes. AA was commonest in two breeds. The incidence of type AB haemoglobin in Baloochi and Kordi breeds was 26.5% (9/34) and 9.5% (2/21), respectively. BB phenotype was not seen in Baloochi and Kordi breeds. In sheep with AB phenotype, haemoglobin B was dominant. The mean +/- SD of the two kinds of haemoglobin in sheep with AB phenotype were haemoglobin B percentage 60.5% +/- 9.04%, haemoglobin B absolute 73.84 +/- 5.44 g/L, haemoglobin A percentage 39.5% +/- 9.04%, haemoglobin A absolute 32.88 +/- 2.89 g/L. There were no significant differences for total haemoglobin, haematocrit, red blood cell (RBC) number, iron and copper levels between breed, sex and age groups and also between sheep with AA phenotype and AB phenotype. Pearson's method showed significant correlations for total haemoglobin with packed cell volume (PCV), RBC number, copper concentration and RBC number with PCV, copper level and PCV with copper amount and copper concentration with iron level (p<0.05). In the Kordi breed, significant correlations were seen for total haemoglobin with PCV, RBC number, copper concentration and PCV with RBC number and RBC number with copper level and copper concentration with iron amount (p<0.05). In the Baloochi breed, significant correlations were detected for total haemoglobin with PCV, RBC number and PCV with RBC number (p<0.05).  相似文献   
47.
In 36 female weaned piglets, the effect of different dosages (0, 300, 600 and 1200 microg/kg feed) of isolated, pure Fusarium toxin deoxynivalenol (DON) was examined during a period of 8 weeks. Standardised trial conditions were provided. Pigs were fed restrictively to allow a complete feed intake of all animals. Parameters of liver integrity, haematological data and blood concentrations of some selected metabolic components of energy and protein metabolism were examined weekly. Enzyme aspartate aminotransferase was affected subclinically by age and significantly by dosage, which was proved by Wald F-test. Some additional enzymes, for instance alanine aminotransferase, gamma glutamyl transferase, glutamate dehydrogenase and sorbit dehydrogenase, showed no clear systematic effect. Urea and glucose in the blood were inter-related. Depending on DON load with increasing glucose concentrations, the urea level declined. Albumin and total protein in serum showed no significant DON-related effect. Haemoglobin in blood was found to be significantly affected by DON, which was proved by the Wald F-test, where the effect was more pronounced with 600 microg DON/kg diet compared to 1 200 microg DON/kg. An obvious DON-related affection of liver, N-metabolism and stimulation of haematopoiesis depending on dosage and time is discussed.  相似文献   
48.
ABSTRACT

1. Sex-specific variations in early embryonic development rates may pre-empt later variations in embryonic development through to pipping and hatching. Given that erythropoiesis (blood production) can be equated with early embryonic growth rate, it was hypothesised that blood pigment haemoglobin can act as a specific spectral fingerprint for changes in growth rate. Moreover, by measuring longitudinal, rather than lateral, spectral transmission through the egg, a more consistent spectrum with a higher signal-to-noise ratio could be captured.

2. Longitudinal visible transmission (T575/T598 ratio), which is sensitive to haemoglobin, was used to monitor sex-specific early embryonic development rate in white layer chicken eggs from d 0 to 8 of incubation. The sex of these eggs was subsequently confirmed two days after hatching.

3. Embryonic development was detectable from d 3 (72 h) of incubation, 36 h earlier than previously reported lateral spectral measurements, supporting the greater sensitivity of longitudinal measurements.

4. At d 3, the mean T575/T598 ratio for male embryos was significantly lower (P < 0.001) (i.e. higher absorbance of haemoglobin) than for female embryos, which was thought to be due to sex-differences in early embryogenesis. On the other hand, female embryos had a significantly lower (P < 0.05) mean T575/T598 ratio than male embryos at d 7 of incubation, presumably due to the combined effects of oestrogen synthesis receptors and enzymes on erythropoiesis in female embryos at this time.

5. In conclusion, the proposed methodology has the sensitivity to differentiate sex-specific embryonic development rates during early incubation and the potentiality to advance precision incubation management and poultry research.  相似文献   
49.
Temperature is considered as an important environmental factor, and the increasing water temperature resulting from global warming is a great concern. The present study was conducted to examine the effects of elevated water temperature on growth, hemato‐biochemical parameters in Nile tilapia, Oreochromis niloticus acclimatized to three temperatures (31°C, 34°C and 37°C) for 60 days. Additionally, erythrocytic cellular abnormalities (ECA) and erythrocytic nuclear abnormalities (ENA) tests were assayed using peripheral erythrocytes after exposure to the three temperatures. Fish were sacrificed on days 7, 15, 30 and 60 of exposure. Growth performances viz., weight gain, % weight gain and specific growth rate (SGR) showed decreasing tendency at 34°C but significantly declined at 37°C compared to 31°C. The abundance of haemoglobin (Hb) and red blood cells (RBCs) significantly decreased in response to temperature increases, while white blood cells (WBCs) displayed the opposite response. At days 7 and 15, blood glucose levels significantly increased in response to the temperature increase, while at days 30 and 60 glucose declined. Frequencies of ECA and ENA were significantly enhanced at the highest temperature throughout the experimental period. Dissolved oxygen decreased and free CO2 increased significantly with increasing temperature throughout the study period. The present study revealed that temperatures higher than 34°C may be hazardous to O. niloticus.  相似文献   
50.
In the present paper are described the growth properties of three different haemoglobin genotypes of juvenile Atlantic cod (Gadus morhua) reared at 7, 10, 13 and 16 °C. In addition one group was reared under temperature steps i.e. moved successively from 16 to 13 and 10 °C. The genotype Hb-I(2/2)displayed the overall highest growth rate in the temperature range 13–16 °C, whereas the Hb- I(1/1)genotype showed the highest overall growth at the lowest temperature (7 °C). Accordingly, we found a significant interaction between genotype and temperature. The differences in growth were largest when cod were reared under the temperature step regime where the Hb-I(2/2)genotype displayed 17 and 24% higher growth than Hb-I(1/1)and Hb-I(1/2),respectively. Optimal temperature for growth (Topt.G) varied between the genotypes with the genotype Hb-I(1/2)displaying the highest (mean ± SE) Topt.G (14.5 ± 1:0.8 °C) and Hb-I(1/1)the lowest (12.5 ± 0.2 °C). The biological significance of this link between biochemical genetic variation and physiological properties might be the influences on growth pattern, ultimate size and age at first maturity.  相似文献   
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