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We had examined the immunogenicity of a series of plasmid DNAs which include neuraminidase (NA) and nucleoprotein (NP) genes from avian influenza virus (AIV). The interleukin-15 (IL-15) and interleukin-18 (IL-18) as genetic adjuvants were used for immunization in combination with the N1 and NP AIV genes. In the first trial, 8 groups of chickens were established with 10 specific-pathogen-free (SPF) chickens per group while, in the second trial 7 SPF chickens per group were used. The overall N1 enzyme-linked immunosorbent assay (ELISA) titer in chickens immunized with the pDis/N1 + pDis/IL-15 was higher compared to the chickens immunized with the pDis/N1 and this suggesting that chicken IL-15 could play a role in enhancing the humoral immune response. Besides that, the chickens that were immunized at 14-day-old (Trial 2) showed a higher N1 antibody titer compared to the chickens that were immunized at 1-day-old (Trial 1). Despite the delayed in NP antibody responses, the chickens co-administrated with IL-15 were able to induce earlier and higher antibody response compared to the pDis/NP and pDis/NP + pDis/IL-18 inoculated groups. The pDis/N1 + pDis/IL-15 inoculated chickens also induced higher CD8+ T cells increase than the pDis/N1 group in both trials (P < 0.05). The flow cytometry results from both trials demonstrated that the pDis/N1 + pDis/IL-18 groups were able to induce CD4+ T cells higher than the pDis/N1 group (P < 0.05). Meanwhile, pDis/N1 + pDis/IL-18 group was able to induce CD8+ T cells higher than the pDis/N1 group (P < 0.05) in Trial 2 only. In the present study, pDis/NP was not significant (P > 0.05) in inducing CD4+ and CD8+ T cells when co-administered with the pDis/IL-18 in both trials in comparison to the pDis/NP. Our data suggest that the pDis/N1 + pDis/IL-15 combination has the potential to be used as a DNA vaccine against AIV in chickens.  相似文献   

3.
Infectious bovine rhinotracheitis (IBR) virus causes vulvovaginitis, abortion and respiratory disease in cows and heifers. Betapropiolactone (BPL) is a disinfectant, effective against bacteria, fungi and viruses. It is also used to prepare inactivated vaccines because it destroys the nucleic acid core of viruses but does not damage the capsid. For the validation of BPL when used as an inactivant, it is more important to assure the quality of inactivating agent and the validity of the inactivation process. In the present study, the inactivation kinetics of IBR virus was determined with different concentration of BPL (1:250, 1:500, 1:1000, 1:1500, 1:2000 and 1:2500) at 4 and 37 °C. The result indicated that the BPL at 4 °C was able to inactivate the IBR virus within 4, 5 and 12 h with the concentration of 1:250, 1:500 and 1:1000, respectively. BPL at 37 °C was able to inactivate virus within 30 min with the concentration of 1:250. BPL with the concentration of 1:500 and 1:1000 were able to inactivate the virus within 120 min at 37 °C. Based on the kinetic study seven formulations were prepared and a sero conversion study of IBR inactivated vaccine was carried out. Serological response in animals to different formulations did not differ significantly (P > 0.05).  相似文献   

4.
This study describes an equine joint friction test using a cartilage-on-cartilage arrangement and investigates the influence of age and load on the frictional response. Osteochondral plugs were extracted from equine shoulder joints (2–5 years, n = 12; 10–14 years, n = 15), and mounted in a pin-on-disc tribometer. The frictional response was then measured under constant conditions (2 N; 20 °C; 5 mm/s), and with increasing load (2 N, 5 N, 10 N). In all experiments, the friction coefficient of young cartilage was significantly (P < 0.001) smaller than obtained from old cartilage, while the application of a greater load resulted in a significant (P < 0.001) decrease in friction coefficient only in old cartilage. It was concluded that cartilage ageing was responsible for an increase in friction coefficient under these experimental conditions. Moreover, where young cartilage lubrication remained stable, cartilage ageing may have been responsible for lubrication regime change. The cartilage-on-cartilage model could be used to better understand lubrication regime disturbances in healthy and diseased equine joints, and to test the efficacy of various bio-lubricant treatments.  相似文献   

5.
Conservation and restoration efforts of native grasslands are being hindered by invasive, exotic plants. Exotic bluestem grasses (Bothriochloa and Dichanthium spp.) have become increasingly invasive throughout the rangelands of the central and southern Great Plains, United States. Accordingly, the aim of this study was to evaluate the efficacy of glyphosate, imazapyr, and imazapyr + glyphosate treatments with or without disking to remove exotic bluestems from a south Texas coastal prairie. We evaluated three different control regimens: 1) herbicide treatments only, 2) herbicide treatments followed by two diskings (H + D), and 3) disking followed by herbicide treatments (D + H). Percent exotic bluestem, native grass, and forb cover were visually estimated at 0 (pre-treatment: May 2006), 20, 52, and 104 wk after treatment (WAT). The herbicide-only and H + D regimens were ineffective at controlling exotic bluestems. However, exotic bluestem cover in herbicide-treated plots of the D + H regimen was significantly lower (P ≤ 0.05) compared to control plots and most treatment plots of the herbicide-only and H + D regimens up to 52 WAT. Control regimens did not notably facilitate an increase in native grass cover from pre-treatment levels, but native grass cover remained the highest, and increased the most, in some imazapyr-treated plots of the herbicide-only and D + H regimens, respectively. In the H + D and D + H regimens, disking resulted in a flush of forb cover (up to 50%) at 52 WAT; yet forb cover was ≤ 5% in these plots by 104 WAT. Exotic bluestem cover recovered back to, or was greater than, pre-treatment levels among most treatment plots across all three control regimens at 104 WAT. This study suggests that follow-up control measures are needed to suppress the re-invasion of exotic bluestems after initial control efforts. Additional studies are needed to evaluate other strategies to control exotic bluestems in rangelands of the central and southern United States.  相似文献   

6.
This study was conducted to determine the effects of cysteamine, hypotaurine and aminoacids solution (BME) on standard semen parameters, lipid peroxidation and antioxidant activities of Angora goat semen after the freeze–thawing process. Ejaculates collected from four Angora goats were evaluated and pooled at 37 °C. Semen samples, which were diluted with a Tris-based extender containing the antioxidants hypotaurine (5 mM) and cysteamine (5 mM), and an aminoacid solution (13%), and an extender containing no antioxidants (control), were cooled to 5 °C and frozen in 0.25-ml French straws in liquid nitrogen. Frozen straws were thawed individually at 37 °C for 20 s in a water bath for evaluation.Supplementation with cysteamine, hypotaurine and BME caused significant (P < 0.05) increases in sperm motility, and significant (P < 0.05) decreases in total abnormality rates in comparison to the control group. While all in vitro treatments did not affect the acrosomal abnormality rates, hypotaurine and BME but not cysteamine significantly (P < 0.05) increased the HOST results as compared to the control group. Supplementation with antioxidants and BME did not significantly affect MDA levels and CAT activity in comparison to the control group (P > 0.05). The antioxidants hypotaurine and cysteamine decreased SOD activity when compared to the BME group and controls (P < 0.001).  相似文献   

7.
Three experiments were conducted to study the influence of level and type of L-carnitine (LC) on performance and rumiasl and plasma metabolites of weanling calves and finishing lambs. Weanling calves (84) grazing dormant dallisgrass-bermudagrass forage were fed a 20% CP supplement to provide 0, 0.5, 1, or 2 g of ruminally unprotected (RUP) LC per calf daily in Exp. 1. There was a linear increase (P=0.01) and cubic response (P=0.03) to RUP LC in growth rate and quadratic changes (P=0.01) in plasma ammonia N (PAN) and plasma urea N (PUN). In Exp. 2, 32 lambs were individually fed 14% CP diets containing 0, 50, 100, or 200 ppm RUP LC or ruminally protected (RP) LC in a 2 × 4 arrangement of treatments. Lambs gained BW faster (P=0.03) and more efficiently (P=0.07) as the LC level increased to 100 ppm and then declined at 200 ppm (quadratic response). Longissimus area decreased (P=0.03), and fat cover tended (P=0.15) to decline, at 50 and 100 ppm LC and increased at 200 ppm (linear and quadratic response). Ruminal ammonia N levels were reduced at 50 ppm LC but increased at greater LC levels (linear, quadratic, and cubic response, P=0.02). Plasma carnitine concentrations increased (P=0.01) as the dietary level of LC increased. Protected LC was more effective than RUP LC in increasing growth rate (P=0.06) and reducing PAN (P=0.1). In Exp. 3, 16 wether and 16 ewe lambs were individually fed corn-based or soybean hull-based diets with 0 or 100 ppm RP LC in a 2 × 2 arrangement of treatments. Lambs fed RP LC gained BW faster and more efficiently (P=0.04) than lambs that were not fed LC. Lambs fed corn-based and soybean hull-based diets responded similarly to RP LC; however, performance was greater (P=0.03) for lambs fed the corn-based diet. Gender of lambs did not influence the response to diet or RP LC. Supplementing the diet with 100 ppm RP LC reduced (P=0.01) ruminal pH and ammonia N. Plasma carnitine concentrations were increased (P=0.01), and PAN was decreased (P=0.04) by feeding 100 ppm RP LC. Ruminnaly unprotected and RP LC were effective in improving growth rate in ruminants; the latter appeared to be more effective in finishing lambs. L-carnitine reduced ruminal ammonia N and plasma glucose and, in some cases, PAN and PUN.  相似文献   

8.
An epidemiologic study was conducted to investigate the incidence and characterize the antimicrobial resistance determinants, analyzing plasmid profiles, and establishing the genetic relationship among β-lactam-resistant isolates of Salmonella Infantis from broilers in Southern Japan. A total of 120 isolates were recovered from 56 flocks belonging to 44 holdings during 2004–2006. The percentages of resistance were as follows: ampicillin (24%), cephalothin (23%), cefoxitin (0%), ceftazidime (11%), cefotaxime (11%), chloramphenicol (0%), kanamycin (7.5%), ofloxacin (20%), oxytetracycline, streptomycin and sulfamethoxazole (100%) and trimethoprim (75%). The incidence of blaTEM-encoded β-lactam resistance in 2004–2006 was significantly higher than in 1998–2003 (P < 0.001). BlnI-digested PFGE patterns generated two related clusters implicated in the dissemination of β-lactam resistance. Two types of plasmid profiles were observed and two plasmids of ca. 50 and 180-kb size were carried by β-lactam-resistant isolates. Streptomycin resistance was conferred by aadA1 (n = 116), aadA1-aadA2 (n = 1), and aadA1-strA-strB (n = 3). Resistances to kanamycin, oxytetracycline, sulfamethoxazole and trimethoprim were conferred by aphA1 (n = 9, 100%), tetA (n = 120, 100%) sul1 (n = 120, 100%) and dfrA5 (n = 90, 100%), respectively. Two types of class 1 integrons were detected: 1.0 kb (n = 120) and, 1.0/1.5 kb (n = 3). Integrons of 1.0/1.5 kb were found in isolates with the aadA1-strA-strB gene combination. For the first time, all S. Infantis isolates showed resistance to at least three classes of antimicrobial agents; and the intestinal tract of healthy poultry was a reservoir of the extended-spectrum cephalosporin-resistant isolates of serovar Infantis.  相似文献   

9.
Neosporosis has been considered the main cause of abortion between the first and the second trimester of pregnancy in cattle. Therefore, the objective of this study was to identify the presence of Neospora caninum DNA obtained from experimental models based on the evaluation of different areas of the fetal nervous system and organs from heifers previously inoculated with NC-1 after or before insemination. This study was performed with Hereford × Nelore (n = 29) heifers and all animals were considered free of diseases at the beginning of the experiment. All animals were bred by fixed-time artificial insemination (TAI) and allocated as follows: (a) seronegative heifers subjected to TAI (TAI, n = 9), (b) heifers infected with N. caninun 60 days prior to TAI (NC-1 + TAI, n = 9), and (c) heifers submitted to TAI and infected with N. caninum 60 days later (TAI + NC-1, n = 11). The pregnancy was confirmed by transrectal ultrasonography 35 days after TAI and evaluated every 30 days until the end of gestation. Fetuses were collected surgically at 170 days of gestation, and immediately necropsied to remove tissues aseptically. Samples of the central nervous system (CNS), heart, kidney, lung, liver, skeletal muscle and caruncle were collected for DNA extraction. Days of gestation at abortion and interval from abortion to first insemination were examined by Student's t-test. At 35 days of gestation the pregnancy rates in the group NC-1 + TAI (4/9, 44.4%) was lower than in the control group (8/9, 88.8%, P < 0.05). At 60 days, the pregnancy rates in the NC-1 + TAI group (0/4, 0%) was lower compared to TAI + NC-1 (5/7, 71.4%) and control (6/8, 75.0%) groups (P < 0.05). Animals from the group NC-1 + TAI were re-inseminated 60 days after the first TAI. After pregnancy losses throughout the study, 5 animals (TAI), 3 animals (NC-1 + TAI) and 5 animals (TAI + NC-1) maintained pregnancy until 170 days of gestation. TaqMan RT-PCR demonstrated the presence of N. caninum DNA in the medulla and right posterior cortex in 3 out of 5 fetuses from the TAI + NC-1 group. We concluded that heifers infected after TAI had a higher incidence of the parasite at the fetus CNS. Identification of N. caninum by TaqMan RT-PCR would assist in the investigation of infection and in the evaluation of vaccines or therapeutic drugs to control neosporosis in cattle.  相似文献   

10.
Staphylococcus intermedius isolates (n = 106), including 44 dog isolates and 62 pigeon isolates, were examined for their susceptibility to ampicillin, cephalexin, erythromycin, gentamicin, kanamycin, lincomycin, norfloxacin, oxacillin, tetracycline, and vancomycin by standard disk-diffusion test. The frequencies of resistance to ampicillin, kanamycin, and tetracycline were significantly higher in dog isolates than pigeon isolates (95.5% vs. 0%, 31.8% vs. 0%, and 45.5% vs. 9.7%, respectively; P < 0.01). Antimicrobial resistance patterns of dog isolates and pigeon isolates were categorized respectively into nine and five distinct profiles. Significantly higher occurrence of resistance to two or more antimicrobials was observed in dog isolates than pigeon isolates (54.5% vs. 12.9%; P < 0.01) and also in domesticated pigeon isolates than non-domesticated pigeon isolates (53.3% vs. 0%; P < 0.01).  相似文献   

11.
Murine forestomach carcinoma (cell line MFC), ascitic hepatoma (cell line H22) and sarcoma (cell line S180) solid tumor models were used to test the anti-tumor effect of Trichinella spiralis in vivo. Mice previously infected by oral administration of 400 viable T. spiralis larvae per mouse for 7 days were grafted with various solid tumor cell lines. Other groups of tumor-bearing mice were given caudal vein injection of crude extracts of adult and newborn larvae at 17.5, 35.0 or 70.0 mg kg?1. These treatments to inhibit tumor growth were dose-dependent (p < 0.05). The anti-proliferative activity of crude T. spiralis extract was examined in vitro at 0.035, 0.070 or 0.140 mg ml?1 using MFC, H22, S180, human chronic myeloid leukemia cell line (K562) and hepatoma cell line (H7402), tumor cell proliferation in vitro was measured by methyl thiazolium stain and was inhibited in dose-dependent manner (p < 0.05). At the same doses, crude T. spiralis extracts induced apoptosis of K562 and H7402 as detected by DNA fragmentation. Cell cycle analysis indicated that crude T. spiralis extracts, at 0.140 mg ml?1, arrested the cell cycle of K562 and H7402 in G1 or S phase. It is concluded that T. spiralis contains anti-tumor active agent.  相似文献   

12.
Salivary chromogranin A (CgA) is considered to be a biomarker of activation of the sympatho-adrenomedullary system, and has recently been proposed as a useful indicator of the acute stress response in pigs. The aim of the present study was to determinate whether salivary CgA concentrations in healthy growing pigs exhibits any circadian pattern during the daytime, and to evaluate its stability under different storage conditions. A total of 80 pigs (40 in spring and another 40 in autumn) of two different ages and genders were used. To establish the circadian pattern, saliva samples were collected at 07.00, 11.00, 15.00 and 19.00 h on two consecutive days. Pooled samples were used for the stability study and were measured on the day of sampling and periodically for up to 360 days later. Samples were stored at 4 °C, ?20 °C or ?80 °C and the effect of repeated freezing and thawing was also evaluated.No circadian pattern was detected for salivary CgA in either season and there were no significant effects of gender or age. However, mean salivary CgA concentrations were significantly higher (P < 0.0001) in the pigs sampled in autumn, compared to those sampled in the spring. Short term storage at 4 °C is recommended for up to 2 days, whereas frozen samples can be stored for 1 year at ?20 °C or ?80 °C, without substantial reduction in CgA values. In addition, samples can be frozen and thawed up to seven times without significant loss of the biomarker.  相似文献   

13.
Up to one-third of dairy calves are born after dystocia and this is a major cause of calf mortality. This study investigated the neonatal physiology, survival, health and subsequent growth of dairy calves following dystocia and is the first longitudinal study to analyse multiple effects and to look beyond the perinatal period.A total of 455 live born Holstein calves (N: No assistance, n = 360; FN: Farmer assistance but normally presented calf, n = 82; FM: Farmer assistance of malpresented calf, n = 13) were followed from birth to first service (heifers) or until leaving the farm (bulls). Compared to N calves, FN and FM animals had higher salivary cortisol concentrations at day 1 (P < 0.001) and FN calves had lower passive immune transfer (P = 0.03). Dystocia had no biologically significant impact on rectal temperature throughout the first 4 days (P > 0.05). During the first 60 days, FM calves had a higher proportion of days with non-routine health treatments (P < 0.05) and, by the time of weaning, mortality in FN and FM heifers was higher than in N calves (2.8×; P < 0.01). However, in surviving calves, growth to first service was not affected by dystocia category (P > 0.05).Calves which survive dystocia experience lower passive immunity transfer, higher mortality and higher indicators of physiological stress. Such calves have poorer welfare in the neonatal period and possibly beyond. Strategies need to be implemented to improve the subsequent health and welfare of such calves and to lower the incidence of dystocia.  相似文献   

14.
Experimental evidence suggests that ruminant animals are capable of selecting a nutritionally balanced diet (i.e. a diet appropriate to their metabolic needs) from imbalanced but complementary foods. We tested this hypothesis by offering calves different combinations of the same complementary foods. A 5 × 5 Latin square design was used to assess the effect on diet selection of different combinations (termed as food A and food B) of two complementary foods (alfalfa-grass hay and maize grain) offered in separate feed bunks. In Treatment 1, food A and food B had the same composition, 50.0% hay and 50.0% grain (T50:50). In the rest of the treatments, hay–grain combinations in foods A and B were, respectively: 62.5–37.5% and 37.5–62.5% (T63:37); 75.0–25.0% and 25.0–75.0% (T75:25); 87.5–12.5% and 12.5–87.5% (T88:12); and 100.0–0.0% and 0.0–100.0% (T100:0). Daily intake data were analysed through repeated measures analysis. Crude protein intake was similar across treatments (P = 0.28). An increasing tendency (P = 0.01) in food B intake (the food with more grain content) from T50:50 to T100:0, however, led into a decreasing tendency (P < 0.001) in the protein: energy ratio of the diet across treatments. Grain consumption in treatments T75:25, T88:12 and T100:0 was higher than expected, leading to protein levels in the diet below those required for a balanced diet (predicted vs. observed: 19.38 vs. 16.67, P = 0.004; 20.53 vs. 16.10, P = 0.001; and 20.23 vs. 16.79 g kgMW? 1 d? 1, P = 0.015, for T75:25, T88:12 and T100:0, respectively). Although calves were potentially able to select a balanced diet in all feeding treatments, they failed when offered high grain foods at choice (75% of maize grain or more). Evolved mechanisms to regulate macronutrient intake under natural conditions may fail to adequately operate in artificial environments involving high-energy density foods (e.g. maize grain).  相似文献   

15.
Incubation of unsensitized sheep red blood cells with serum from the American crocodile (Crocodylus acutus) resulted in a concentration-dependent hemolysis. The hemolytic activity was heat-sensitive, and inhibited by EDTA in a concentration-dependent manner. The EDTA-inhibited SRBC hemolysis could be restored by the addition of excess Ca2+ or Mg2+, but not Ba2+ or Cu2+, revealing the specificity of this activity for these two divalent cations. The hemolytic activity of crocodile serum was titer-dependent, with 329 μL producing 50% of maximal SRBC hemolysis. The complement activity was also temperature-dependent, with decreased activity at lower temperatures (5–15 °C) and maximal activity occurred at 30–40 °C. The hemolysis occurred relatively slowly, with near zero activity after 10 min, 40% of activity observed within 15 min of exposure to SRBCs, and maximal activity at 30 min.  相似文献   

16.
Fifty nine primiparous sows PIC Camborough 23 were distributed in a completely randomized 2 × 2 (with and without floor cooling × two dietary treatments) factorial design with 16 sows/treatment, each sow being considered as an experimental unit. Four replicates of sixteen sows each were used during the trial with the objective of evaluating the effects of floor cooling and the use of dietary amino acid contents on their performance and behaviour during summer. The sows were distributed among the treatments according to body weight and backfat thickness after farrowing. The sows were maintained in the experiment until weaning at 21 days of lactation. The two experimental diets supplied the same levels of crude protein (22%), metabolizable energy (ME; 14.65 MJ/kg) and levels of essential digestible AA relative to digestive lysine and differed according to the digestible lysine to ME ratio (0.75 vs. 0.82 g/MJ of ME). The temperature of the water circulating in the cooled floor was maintained at about 17 °C. Based on the average minimum and maximum temperatures (21.5 and 29.5 °C) obtained during the experimental trial, it can be assumed that the sows were exposed to periods of heat stress. The replicate and the interaction between replicate and treatment effects on all the measurements were not significant. Similarly, no effect of diet or interaction between diet and floor cooling system was found for all criteria measured. An effect (P < 0.05) of floor cooling on average daily feed intake was observed and floor cooling sows showed a higher average (P < 0.05) digestible lysine (61.5 vs. 51.8 g/d) and ME (78.2 vs. 65.9 MJ/d) intakes. The sows submitted to floor cooling showed, consistently, higher absolute values for average weight (+ 8.5 kg) and backfat (+ 0.75 mm) at weaning, compared with the control sows. The sows submitted to the cooled floor showed a shorter (P < 0.01) weaning-to-oestrus interval. The piglet and litter's daily weight gain (DWG), average weight at weaning (AWW) and total weight gain during lactation (TWG) were higher (P < 0.01) for the floor cooling sows. The floor cooling sows showed a higher (P < 0.01) daily milk production. The respiratory rate and rectal temperature values were lower (P < 0.01) for the floor cooling sows. There were differences (P < 0.01) on the cutaneous temperatures measured on the different parts of the sow's body, with the animals submitted to the cooled floor having lower values. The sows submitted to floor cooling spent less (P < 0.01) time in lateral recumbency inactive, more time nursing (P < 0.05) and more time feeding (P < 0.01) compared with control sows. The floor cooling under the sows increased daily feed intake and lysine intake, leading to a lower body weight loss, a lower weaning-to-oestrus interval and also improved nursing behaviour of the sows, leading to a higher milk production and, consequently, higher weight gains of piglets and litter during the lactation period.  相似文献   

17.
Parascaris equorum generally infects horses less than 18 months old and its pathological effects can be severe. Infection occurs when larvated eggs, present in pastures, paddocks, stalls, and on feeding and watering equipment are ingested. The purpose of this study was to examine the effects of windrow composting on the viability of P. equorum eggs at a cooperating central Kentucky horse farm. Three grams of feces containing 2216 P. equorum eggs per gram were sealed in filter bag sentinel chambers. Chambers were exposed to 1 of 3 treatments: constant exposure or intermittent exposure to the interior of the windrow; controls were stored at 4 °C. At day 0, all chambers in the experimental treatments were placed in the center of 10 locations of the windrow. On subsequent days when the windrow was turned, chambers in the constant exposure treatment were returned to the interior of the windrow and chambers in the intermittent exposure treatment were alternated between resting on top of, or inside, the windrow. Chambers from each treatment and control chambers were removed at days 2, 4, 6, 8, 10, 12, 14, and 18; and incubated for 21 days at room temperature (24 °C). After incubation, eggs were recovered from the chambers using double centrifugation flotation. Eggs were evaluated microscopically, staged according to development and classified as viable or nonviable based on whether embryonation to the larval stage had occurred. Results were reported as the mean percent viable eggs for each treatment and time point. A mixed linear model with repeated measures was used to evaluate the influence of experimental day and treatment on the percent viability of P. equorum eggs. Chambers treated with constant exposure contained 10.73% (SD = 0.29) viable eggs on day 2 and declined to an average of 0.00% by day 8. Chambers exposed to the intermittent treatment contained 16.08% (SD = 0.26) viable eggs on day 2 and decreased to 0.00% by day 6. Control chambers for days 2, 4, 6, 8, 10, 12, 14, and 18 all had viabilities above 79.00%. A significant fixed effect of experimental day (p < 0.0001) and compost treatment (p < 0.0001) was observed. There was no significant interaction between experimental day and compost treatment (p > 0.7459). The results of this study demonstrate that windrow composting was effective at rendering P. equorum eggs nonviable when it was tested under the conditions at a working horse farm.  相似文献   

18.
The objective was to investigate the effect of sea transport on the physiological, behavioural and performance responses of bulls. One-hundred and eleven bulls (mean body weight (standard error of the mean) 429 (5.7 kg)) were randomly assigned to one of three treatments; control (C; n = 54) bulls were housed in 6 pens at Teagasc, Grange Research Centre at a stocking density of (1), 1.7 m2/head (C1.7; 3 pens) and (2), 3.4 m2/head (C3.4; 3 pens) and (3), transported (T) bulls (n = 57) were penned at a space allowance of 1.7 m2/head (6 pens) and allocated to one of five decks on the shipping vessel. C and T bulls were subjected to the same live weight (d −2), blood sampling and rectal temperature (d −1) measurements pre-transport and on d 3, d 6, d 9 and d 11 of the study. T bulls had greater (P < 0.05) live weight gain (+4.4%) compared with C1.7 bulls (−2.0%) and C3.4 (+0.13%)). Time spent lying was greater (P < 0.05) among C1.7 and C3.4 bulls (9.9% and 53.3%, respectively) compared with T bulls (45.8%). Rectal body temperature was not different (P > 0.05) among treatment groups throughout the study. At d 11, neutrophil % was greater (P < 0.05) in transported bulls on decks 1, 2, 4 and 5 compared with C1.7 and C3.4 treatments. Plasma cortisol concentrations were not different (P > 0.05) between control and transported bulls. Plasma creatine kinase (CK) activity was lower (P < 0.05) among C3.4 and T bulls on decks 2, 3, 4 and 5 compared with d 3 values. In conclusion, the welfare of bulls transported by sea on the sea journey was not adversely affected. Housing control bulls at a reduced space allowance (1.7 m2) had a negative effect on live weight gain.  相似文献   

19.
To assess the antinociceptive efficacy of transdermal (TD) buprenorphine (B) in dogs, a prospective, positive-controlled experimental study was performed in 10 healthy Beagles. In an open label crossover design, the dogs initially received intravenous B (IVB, 0.02 mg kg?1) as a positive control, followed by TDB (52.5 μg h?1) 4 months later. Blood was collected at regular intervals for determination of the plasma concentrations of B ([B]) and its metabolite norbuprenorphine. The antinociceptive efficacy was assessed using thermal and mechanical models of nociception. The peak concentration [B] was 1.54 ng mL?1 (±1.98) 60 h after TDB application, although three dogs had no measurable [B] after TDB. Maximum thermal threshold (TT) was 52.6 °C (±0.48) at 1 h after IVB administration and 51.63 °C (±1.01) 72 h after TDB application. The significant increase in TT indicated that effective antinociception was achieved beyond 36 h after the application of TDB, lasting until patch removal. There was hysteresis between [B] and the antinociceptive effect.  相似文献   

20.
The objective of this study was to evaluate synchronization and pregnancy rates of beef heifers supplemented with 0.91 kg of whole sunflower seeds for 0, 30, or 60 d before AI. Beef heifers from four locations (n = 1,014) were assigned by BW to treatment (within location) and randomly to AI sire. Heifers at Location 1 (n = 176; mean BW = 332 kg) received either 0- or 60-d sunflower seed treatments. Heifers at Location 2 (n = 397; mean BW = 334 kg) were fed sunflower seeds for 0, 30, or 60 d. Heifers at Locations 3 (n = 211; mean BW = 345 kg) and 4 (n = 230; mean BW = 343 kg) received 0- or 30-d sunflower seed treatments. Within location, diets were formulated to be isocaloric and isonitrogenous. All heifers received melengesterol acetate (0.5 mg/d per head) for 14 d followed 19 d later by an injection of prostaglandin F2a (PGF) (25 mg). Heifers were bred by AI according to the AM/PM rule except on d 3 when all heifers that had not exhibited estrus were artificially inseminated in mass. Neither 72-h estrous response nor pregnancy rate was affected (P>0.10) by 30- or 60-d sunflower feeding. In summary, feeding 0.91 kg of whole sunflower seeds for either 30 or 60 d before AI did not improve estrous response or pregnancy rate when compared with controls.  相似文献   

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