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1.
Cañahua (Chenopodium pallidicaule Aellen) is a semi‐domesticated relative of quinoa (Chenopodium quinoa Willd.) with high nutritious quality. It is tolerant to frost, drought, saline soils and pests. One seed yield limitation is seed loss during the maturity stages. Two greenhouse experiments in Denmark and field experiments in Bolivia were carried out to determine seed shattering in landraces and cultivars with different growth habits. 15–21 % of the seed shattering in the fields took place whilst the plants still were flowering and 25–35 % during physiological maturity. Seed shattering varied between locations on the Bolivian Altiplano. Cañahua types with the semi‐prostrate growth (‘lasta’) had the highest seed shattering rate in the greenhouse experiments. The Umacutama landrace had lower seed shattering (1 %) than the cultivar Kullaca (7.2 %) both of the ‘lasta’ type. Under field conditions, the cultivar Illimani with the erect growth (‘saihua’) had the highest seed shattering rate (6.4–33.7 %) at both locations and at four different sowing dates. The Umacutama had the lowest rate (0.5–1.5 %). There were no significant differences between plants of the ‘lasta’ and the ‘saihua’ types. The landrace had significantly less seed loss than the cultivars. However, in the greenhouse, the landrace yield was approximately 25 % lower than the yields of the cultivars. In general, cañahua cultivars had higher yield compared to landraces, but also a higher seed shattering rate. Landraces may be used in breeding programmes to develop high‐yielding cultivars with reduced seed shattering.  相似文献   
2.
Caudal epidural analgesia is a well-established therapeutic modality for pain alleviation in horses. Additionally, epidural analgesia could potentially be a complementary diagnostic tool for confirmation of pain-related conditions in horses presenting with nonspecific signs of poor performance or rideability issues. To use the epidural as a diagnostic tool, the administered medications should provide efficient analgesia without accompanying adverse effects. Therefore, the objectives of the current study were to evaluate the analgesic properties and effects on locomotor function, mentation and physical examination parameters of caudal epidural co-administration of methadone and morphine in horses. Five mares received a caudal epidural injection of 0.1 mg/kg bwt methadone and 0.1 mg/kg bwt morphine diluted to a total volume of 4.4 mL/100 kg. Before and several times thereafter, horses were subjected to mechanical nociceptive threshold evaluation, physical examination, assessment of mentation and locomotor function examination. Horses were assigned ataxia scores (0–4) by a group of inexperienced raters (three senior-year veterinary students) and a group of experienced raters (two board-certified internal medicine specialists) that assessed the locomotor examinations either live or video-based. The epidural co-administration of methadone and morphine resulted in clinically relevant and statistically significant increases of horses’ tolerance to mechanical noxious stimuli at the coccygeal, perineal, sacral, lumbar and thoracic regions. Analgesia was evident after 4.4 h and lasted at least 5 h. Regional differences in the onset of analgesia reflected a cranial spread of the analgesic solution. No horses showed signs of gait disturbances; the overall median ataxia score was 0 at all times; and the average difference in scores between two randomly selected raters for a random horse at a random time point was 0.377 indicating high inter-rater agreement. There were no adverse changes of mentation and physical examination parameters. Observed side effects included signs of decreased frequency of defaecation, generalised sweating, and pruritus.  相似文献   
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An integrated SPF herd with 320 sows was found infected with Salmonella Yoruba during an annual control among sows, aiming to verify freedom from Salmonella infections. It is believed that the infection was introduced to the herd by purchase of feed. The herd performed an age segregated rearing system. Sows and piglets were reared at a central farm, while growers (25-100 kg body weight) were reared at sub-estates. The growers were free from the infection, and as a consequence a specially designed eradication program was designed. Farrowing and weaning were defined as periods of risk for sows and piglets, respectively. Consequently sows were isolated and individually tested for presence of Salmonella one week before and one week after farrowing. The offspring were tested one week post weaning. To verify freedom from disease among piglets they were also tested another time before transfer to the uninfected sub-estates. Piglets with undefined status regarding Salmonella were denoted animals at risk and not transferred to the sub-estates. Instead they were transferred to a third estate, rented to house pigs at risk. The program was successful. It allowed full production during performance, and the herd was declared free from S. Yoruba seven and a half months after the initial diagnosis.  相似文献   
5.
The efficacy of a single intraperitoneal injection of oxolinic acid to control an outbreak of atypical Aeromonas salmonicida infection in goldsinny wrasse (Ctenolabrus rupestris) and in the treatment of systemic vibriosis in corkwing wrasse (Symphodus melops) was examined. In addition a field study was performed to examine the effect of medication on the survival rate of goldsinny wrasse in Atlantic salmon cages. Four groups of wild caught goldsinny wrasse, each of 50 fish, were treated with an intraperitoneal injection of propylene glycol:saline (50:50) (control) or 50 mg/kg oxolinic acid at a concentration of 50 mg/mL. Three days after medication the fish in all groups were treated by an intraperitoneal injection of prednisolone acetate and an increase in seawater temperature from 9.0 to 11.5 degrees C. Cumulative mortalities were 18% in the two groups treated with oxolinic acid and 94 and 100% in the unmedicated control groups, giving a 'relative percentage survival' (RPS) value of 82%. A laboratory maintained population of originally wild caught corkwing wrasse experiencing high daily mortality was treated with oxolinic acid (50 mg/kg) or propylene glycol:saline (control). Cumulative mortalities were 84% (control) and 42% (oxolinic acid medicated group) giving an RPS value of 50%. In a field investigation using goldsinny wrasse approximately 30% were medicated with oxolinic acid (50 mg/kg) prior to stocking in cages with Atlantic salmon. In two of three cages the cumulative mortality was significantly lower (P = 0.025 and P < 0.001) in the medicated groups.  相似文献   
6.
The objectives of this study were to elucidate at which age tonsillar colonisation by Actinobacillus pleuropneumoniae occurs in pigs and relate this occurrence to the presence of colostral antibodies to A. pleuropneumoniae. The infection patterns were studied in an isolated cohort of pigs, which consisted of the offspring from five sows originating from a conventional pig herd. The sows were transferred to isolated research facilities before farrowing. A. pleuropneumoniae was detected on the tonsils of all sows. After a nursing period of 3 weeks, the pigs were weaned and reared isolated from other pigs until slaughter. The pigs were examined repeatedly for the presence of A. pleuropneumoniae on the tonsils and for antibodies to A. pleuropneumoniae using bacteriological and serological techniques, respectively.A. pleuropneumoniae was detected in the tonsils of one pig as early as 11 days after birth, showing that A. pleuropneumoniae can be transmitted from sow to offspring during a 3-week nursing period. The cumulative proportion of pigs carrying A. pleuropneumoniae in their tonsils increased significantly between the age of 4-12 weeks. This age period corresponded to the age at which the proportion of pigs with detectable levels of colostral antibodies to the different serotypes of A. pleuropneumoniae was declining. Since these two events take place in the same age period, we expect a possible biological association between the level of the passive immunity and the degree of tonsillar colonisation. The median duration of tonsillar colonisation was estimated to approximately 7-8 weeks.  相似文献   
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High mortality rates are often observed in rearing the early stages of the great scallop, Pecten maximus. The addition of antibacterial agents has been necessary to improve larval survival. However, as one antibacterial agent, chloramphenicol, is banned in Norway and Europe the aim of this study is to investigate alternative antibacterial agents. The therapeutic agents investigated in this study were florfenicol, oxytetracycline, oxolinic acid, neomycin and Pyceze. The mean minimum inhibitory concentration (MIC) values were determined for oxytetracycline, oxolinic acid and Pyceze against bacteria isolated from scallop larvae. Two types of treatment regime were investigated on an intermediate scale (20 L). One regime involved continuous exposure of scallop larvae to the therapeutic agent while the other involved a short exposure lasting two hours. All intermediate scale treatments were performed in parallel to large-scale production (800 L) treatment with chloramphenicol. Of the therapeutants investigated, oxolinic acid was the most effective, although only at high concentrations. The short exposure of two hours was ineffective for all therapeutics.  相似文献   
9.
In this investigation, the efficacy of a single intraperitonealinjection of either flumequine or oxytetracycline hydrochloride to preventoutbreak of atypical Aeromonas salmonicida infection ingoldsinny wrasse, Ctenolabrus rupestris, following stresswas studied. Six groups of goldsinny wrasse, each of 50 individuals, weretreated with an intraperitoneal injection of either propylene glycol : saline(50 : 50), 200 mg kg–1 of oxytetracycline or 50mg kg–1 of flumequine dissolved in propyleneglycol : saline (50 : 50). Three days following medication the fish in allgroups were stressed by an intraperitoneal injection of prednisolone acetate(0.05 ml) and a rise in seawater temperature from 9 to 11°C. Mortality was observed daily for 21 days. Flumequine wasthe more effective with a mean cumulative mortality of 5% compared tooxytetracycline with 54%. The mean cumulative mortality in the unmedicatedcontrol groups was 84%. Bacterial examination of kidneys from dead fishconfirmed the presence of atypical A. salmonicida as theprobable cause of death. Minimum inhibitory concentration (MIC) values forflumequine and oxytetracycline against the isolated A.salmonicida were determined to 0.13 gml–1, and 2.0 g ml–1,respectively.  相似文献   
10.
Three different concentrations (107, 105 and 103 TCID50 ml-1) of infectious pancreatic necrosis virus (IPNV) serotype Sp isolated from Atlantic halibut, Hippoglossus hippoglossus L., were used to bath-challenge Atlantic halibut yolk-sac larvae. The larvae challenged with 107 TCID50 ml-1 suffered significantly higher cumulative mortality than the other challenged groups and the control group, and affected individuals displayed necrosis of the intestine, liver and kidney. In larvae from the groups challenged with 107 and 105 TCID50 ml-1, IPNV was detected by immunohistochemistry and in situ RNA/DNA hybridization in the intestine, liver and kidney. In addition, some individuals stained IPNV-positive in the heart and eye/brain region. Detection by in situ hybridization did not appear to be more sensitive than immunohistochemistry. However, background staining was virtually absent in comparison with immunohistochemistry, and the staining seemed to be more distinctly localized to the cytoplasm of infected cells. The results show that farmed halibut yolk-sac larvae can be infected by IPNV immediately after hatching, with resulting high mortality. As the larvae are not immunologically mature at this stage of development, vaccination is not recommended.  相似文献   
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