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131.
Stuart J Rowland Mark Nixon Matthew Landos Charlie Mifsud Phil Read & Peter Boyd 《Aquaculture Research》2006,37(9):869-876
Infestations of parasitic monogenean trematodes (Lepidotrema bidyana and Gyrodactylus sp.) on freshwater silver perch (Bidyanus bidyanus Mitchell) in earthen ponds were treated with formalin (37% formaldehyde). Concentrations of 30 and 40 mg L?1 formalin were effective, but fish in ponds treated with 20 or 25 mg L?1 remained infested. At temperatures of 24.1–26.9°C, concentrations of 30 or 40 mg L?1 formalin caused dissolved oxygen (DO) to decline from 10.1–11.9 to 3.0–3.3 and 1.2–1.7 mg L?1, respectively, within 36–42 h of treatment. In addition, pH declined from 7.2–8.4 to 6.3–6.7, within 36 h and turbidity decreased over 48 h. In the ponds where DO was 1.2–1.7 mg L?1, silver perch showed signs of severe stress, but continuous aeration (10 hp ha?1) for 3 days and inflow of well‐oxygenated water for 6–8 h prevented mortalities. At temperatures of 13.2–15.7°C, concentrations of 30 or 40 mg L?1 formalin caused DO to decline from 9.0–10.0 to 6.0–8.1 mg L?1 and pH from 7.0–7.3 to 5.9–6.6 within 72 h. Total ammonia‐nitrogen increased over 72 h in ponds treated with 30 or 40 mg L?1 formalin. Fish became re‐infested with L. bidyana in all ponds within 30 days of treatment. A concentration of 30 mg L?1 formalin is recommended as a treatment for monogeneans on silver perch in ponds, but aeration is necessary to maintain adequate water quality at higher temperatures. 相似文献
132.
Sensing and control system for spot-application of granular fertilizer in wild blueberry field 总被引:1,自引:0,他引:1
Young Ki Chang Qamar Uz Zaman Aitazaz Farooque Hassan Chattha Scott Read Arnold Schumann 《Precision Agriculture》2017,18(2):210-223
An automated sensing and control system (hardware and software) was developed for real-time spot-application of granular fertilizer in mowed wild blueberry fields. The custom hardware system was incorporated into a commercial pneumatic granular fertilizer spreader. Custom software for the sensing and control system was developed by combining color co-occurrence matrix based texture analysis and g-ratio algorithms in C++ to acquire and process images in real-time to differentiate mowed wild blueberry plants from bare spots and weeds. The performance accuracy of the spot-applicable fertilizer spreader was evaluated both in laboratory simulation and real-time field tests. Simulation results reported that the accuracy of the developed system was 94.9 %. Real-time field tests reported that the system produced acceptable results at ground speeds of 1.6 and 3.2 km h?1 for the spot-application of fertilizer at target areas (in plant areas only) within the field. Results also indicated that the ground speed of 4.8 km h?1 was unacceptable, which could be due to blurred images at high speed and surface unevenness of the wild blueberry field. Spot-application of fertilizer using the modified fertilizer spreader could save fertilizer for the wild blueberry producers. 相似文献
133.
The objectives of the present study were to determine ionic and organic composition of seminal plasma, sperm concentration and their relationships in the Persian sturgeon (Acipenser persicus). In this regard, ionic content (Na+, K+, Cl?, Ca2+ and Mg2+) and organic content (total protein, glucose, cholesterol and triglyceride) along with sperm concentration were measured in 17 specimens of the Persian sturgeon. The seminal plasma contained 59.53 ± 2.56 mm /l sodium, 9.1 ± 1.42 mm chloride, 4.72 ± 0.3 mm potassium, 1.45 ± 0.075 mm calcium and 0.7 ± 0.072 mm magnesium. The following organic contents were found: total protein 0.11 ± 0.02 g/dl, glucose 22.18 ± 4.16 mg/dl, cholesterol 6.67 ± 1.04 mg/dl and triglyceride 15.2 ± 0.65 mg/dl. The mean sperm concentration was estimated to be 1.6 ± 0.12 (×109 sperm/ml). A significant relationship was found between sperm concentration and K+ of seminal plasma (r = 0.533, p < 0.05). Significant correlations were observed between ionic contents: Na+ vs Cl? (r = ?0.854, p < 0.01) and Mg2+ vs K+ (?0.583, p < 0.05). Also, level of triglyceride was negatively correlated with Mg2+ (r = ?0.503, p < 0.05). Presented data could be considered as a complementary study for developing special extenders and protectant solutions for improving artificial fertilization in this valuable species. 相似文献
134.
M Grzesiak K Knapczyk‐Stwora MR Luck A Mobasheri M Slomczynska 《Reproduction in domestic animals》2016,51(1):105-113
The growth of ovarian follicles is accompanied by fluid‐filled antrum formation. Water movement within the follicular wall is predominantly transcellular via membranous water channels named aquaporins (AQPs). Androgens are important regulators of mammalian folliculogenesis, and their prenatal and/or neonatal deficiency affects female fertility in adulthood. Therefore, this study was performed to determine whether gestational or neonatal exposure to the anti‐androgen flutamide influences androgen‐dependent AQP5 expression in pre‐antral and large antral follicles of adult pigs. Flutamide was injected into pregnant gilts between days 80 and 88 of gestation and into female piglets between days 2 and 10 post‐natally. The ovaries were collected from flutamide‐treated and non‐treated (control) sexually mature pigs. In pre‐antral follicles, AQP5 mRNA and protein levels were both downregulated following maternal (p < 0.01 and p < 0.01, respectively) and neonatal (p < 0.01 and p < 0.01, respectively) flutamide exposure. Likewise, the expression of mRNA (p < 0.01 and p < 0.001, respectively) and protein (p < 0.05 and p < 0.01, respectively) for AQP5 were diminished in large antral follicles in both groups. Immunohistochemistry showed decreased intensity of AQP5 immunoreaction in pre‐antral (p < 0.01) and large antral (p < 0.001) follicles following flutamide treatment. Moreover, radioimmunological analysis revealed that changes observed in AQP5 expression corresponded with diminished follicular androgens production after both maternal (p < 0.05 and p < 0.05, respectively) and neonatal (p < 0.05 and p < 0.01, respectively) flutamide administration. Therefore, AQP5 appears to be a potential regulator of follicular fluid accumulation, under androgen control, and may be a key factor in antral follicle growth. 相似文献
135.
Objective
To compare the analgesic efficacy and suitability of an existing oral tramadol-based protocol with a transdermal fentanyl-based protocol following lateral thoracotomy in dogs.Study design
Prospective randomized clinical trial.Animals
A group of 16 healthy laboratory beagle dogs.Methods
Dogs were randomly allocated to one of two treatment groups: group F (intramuscular methadone 0.2 mg kg–1 and transdermal fentanyl 2.6 mg kg–1 both administered on discontinuation of anaesthesia, n = 8) or group T (intramuscular methadone 0.2 mg kg–1 on discontinuation of anaesthesia and again 4 hours later, followed by oral tramadol 12 mg kg–1 per 24 hours commencing 7 hours after discontinuation of anaesthesia, n = 8). Intercostal bupivacaine (0.5–1 mg kg–1) and subcutaneous carprofen (4 mg kg–1) were administered to all dogs at induction. Body weight (BW), presence of clinical signs, pain score, activity, heart rate (HR) and mean arterial pressure (MAP) were assessed for 72 hours postoperatively.Results
No significant differences were observed in BW change, presence of clinical signs or gross locomotor activity between groups. Pain scores were low at all times for all dogs, and rescue analgesia was not required. Dogs in group T exhibited higher pedometric activity (p = 0.006), HR (p < 0.001) and MAP (p < 0.001) than those in group F, in particular on night 1 following surgery. Least squared mean (LSM) pedometric activity was 1.81 and 1.02 jerks minute–1, LSM HR was 111.13 and 78.64 beats minute–1 and LSM MAP was 111.62 and 105.24 mmHg, respectively, in groups T and F.Conclusions and clinical relevance
Both regimes appear to provide adequate analgesia following lateral thoracotomy in dogs. Ease of administration of transdermal fentanyl compared to oral tramadol is advantageous. Reduced activity observed with the fentanyl regime was not associated with any adverse effects and may be desirable following some invasive surgeries. However, while transdermal fentanyl remains currently unavailable in the European Union, the oral tramadol-based regime provides an acceptable alternative. 相似文献136.
137.
Our vigilant immune systems are ready to mount an attack as soon as an invading pathogen is spotted. But what is the cost of keeping this sophisticated defense system on red alert? In a provocative Perspective, Read and Allen discuss new findings showing that the cost of immune defense in animals is very high (Moret and Schmid-Hempel), and the claim that, in some circumstances, the cost may be worth the benefit gained (Nunn et al.). 相似文献
138.
D. A. Read M. F. Palacios J. Kleynhans J. Figueroa L. Foguet B. Stein G. Pietersen 《European journal of plant pathology / European Foundation for Plant Pathology》2018,151(2):329-340
Citrus tristeza virus (CTV) is the most severe viral pathogen of citrus and elicits a wide range of devastating disease symptoms. Grapefruit cultivars (Citrus x paradisi) are the most sensitive among citrus to the effects of CTV infections. Grapefruit is an important crop within the north-western Argentine citrus industry; however, production has been affected by CTV stem-pitting. In general, CTV diversity within South America is poorly studied, with data on grapefruit CTV populations being particularly limited. In this study, 50 samples were collected from Star Ruby, Henninger’s Ruby and Ruben Pink cultivars, within the provinces of Tucumán, Salta and Jujuy in north-western Argentina. The CTV p33 gene was PCR amplified and the resulting amplicons sequenced with Sanger sequencing. A subset of these amplicons was sequenced with Illumina MiSeq sequencing. AT-1-like sequences were dominant within the majority of populations, as determined by Sanger sequencing, followed by sequences clustering within the unresolved Kpg3/SP/T3 and RB clades. Sequencing by Illumina MiSeq confirmed this, as well as detecting minor sequence types within the HA 16–5, VT, B165 and A18 clades. 相似文献
139.
K.E. Moseby J.L. Read D.C. Paton P. Copley B.M. Hill H.A. Crisp 《Biological conservation》2011,144(12):2863-2872
Ten reintroduction attempts were conducted in and around the Arid Recovery Reserve in northern South Australia between 1998 and 2008. Five locally-extinct mammal species and one reptile species were reintroduced into a fenced Reserve where cats, foxes and rabbits were excluded. Reintroductions of the nationally threatened greater stick-nest rat, burrowing bettong, greater bilby and western barred bandicoot were all considered successful based on short and medium-term success criteria. These criteria included continued survival after 8 years, increased distribution across the large Reserve and, most importantly, recovery after a drought event. The trial reintroductions of the numbat and woma python into the Reserve were unsuccessful due to predation by native avian and reptilian predators respectively. Outside the Reserve, where cats and foxes were present but controlled through poison baiting, reintroduction attempts of the greater bilby and burrowing bettong were unsuccessful. High mortality was attributed to cat and fox predation with dingoes also contributing to post-release mortality in bettongs. However, a reintroduction of burrowing bettongs into a fenced area with low rabbit and cat abundance has, to-date, met short-term and medium-term success criteria. Results suggest that the absence or severe restriction of exotic mammalian predators was the critical factor responsible for the success of the mammal reintroductions. Determining thresholds of predator activity below which successful reintroduction of threatened species can occur, are needed to improve the science of reintroduction biology in Australia. 相似文献
140.
SD JOHNSTON D. OBOYLE AJ FROST MR MCGOWAN A. TRIBE D. HIGGINS 《Australian veterinary journal》1998,76(5):335-338
Aim To determine the normal microbial flora of the koala ejaculate and prepuce in order to select appropriate antibiotics for addition into diluents designed for the preservation of semen.
Procedure Bacteriological samples of the koala prepuce (n = 12) and ejaculate (n = 20) were submitted for microbial culture and sensitivity testing. Microbial flora of ejaculates collected by electroejaculation and artificial vagina were compared. The effects of varying concentrations of penicillin G and gentamicin on sperm motility and on the growth of bacteria in diluted semen stored at room temperature and 16°C over a 24 h period were investigated.
Results A range of bacteria was isolated from the koala prepuce and ejaculate. The predominant organisms in semen collected by electroejaculation and artificial vagina were Corynebacterium spp, none of which could be assigned to any recognised species. The addition of penicillin G and gentamicin to a PBS-based diluent at dose rates of 1000 to 2000 IU/mL and 100 to 200 m g/mL respectively, resulted in no adverse effect on sperm motility over a 24 h incubation period. Penicillin G (1000 IU/mL) and gentamicin (100 m g/mL) prevented growth of bacterial contaminants in diluted koala semen.
Conclusion By controlling the growth of bacteria in extended koala semen, penicillin G and gentamicin are likely to lengthen the period by which spermatozoa can be stored at 16°C and reduce the possibility of disease transmission during artificial insemination procedures. 相似文献
Procedure Bacteriological samples of the koala prepuce (n = 12) and ejaculate (n = 20) were submitted for microbial culture and sensitivity testing. Microbial flora of ejaculates collected by electroejaculation and artificial vagina were compared. The effects of varying concentrations of penicillin G and gentamicin on sperm motility and on the growth of bacteria in diluted semen stored at room temperature and 16°C over a 24 h period were investigated.
Results A range of bacteria was isolated from the koala prepuce and ejaculate. The predominant organisms in semen collected by electroejaculation and artificial vagina were Corynebacterium spp, none of which could be assigned to any recognised species. The addition of penicillin G and gentamicin to a PBS-based diluent at dose rates of 1000 to 2000 IU/mL and 100 to 200 m g/mL respectively, resulted in no adverse effect on sperm motility over a 24 h incubation period. Penicillin G (1000 IU/mL) and gentamicin (100 m g/mL) prevented growth of bacterial contaminants in diluted koala semen.
Conclusion By controlling the growth of bacteria in extended koala semen, penicillin G and gentamicin are likely to lengthen the period by which spermatozoa can be stored at 16°C and reduce the possibility of disease transmission during artificial insemination procedures. 相似文献