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91.
Objectives To define the prevalence of Bartonella spp., Rickettsia felis, Mycoplasma haemofelis, ‘Candidatus Mycoplasma haemominutum’ (Mhm) and ‘Candidatus Mycoplasma turicensis’ (Mtc) in cats and their fleas in eastern Australia. Design and procedure Conventional PCR assays that detect Bartonella spp., M. haemofelis, Mhm, Mtc, Rickettsia spp., Ehrlichia spp., Anaplasma spp. and Neorickettsia spp. were performed on DNA extracted from blood and fleas collected from 111 cats. Cat sera were assayed by ELISA for IgG of Bartonella spp. Results DNA of M. haemofelis, Mtc and Mhm was amplified from 1 (0.9%), 1 (0.9%) and 17 cats (15.3%), respectively. Only DNA of Mhm was amplified from the 62 of 111 pooled flea samples (flea sets; 55.9%). Overall, the prevalence rates for Bartonella spp. DNA in the cats and the flea sets was 16.2% (18 cats) and 28.8% (32 flea sets), respectively. Bartonella spp. IgG was detected in 42 cats (37.8%), of which 11 (26.2%) were positive for Bartonella spp. DNA in their blood. R. felis DNA was amplified from 22 flea sets (19.8%), but not from cats. Overall, DNA of one or more of the organisms was amplified from 27% (30) of cats and 67.6% (75) of the flea sets. Conclusions This is the first Australian study to determine the prevalence of R. felis and B. clarridgeiae in both fleas and the cats from which they were collected. Flea-associated infectious agents are common in cats and fleas in eastern Australia and support the recommendation that stringent flea control be maintained on cats.  相似文献   
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The primary objective of this study was to investigate the impact of animal‐level factors including energy balance and environmental/management stress, on the ovarian function of Bos indicus heifers treated to synchronize ovulation. Two‐year‐old Brahman (BN) (n = 30) and BN‐cross (n = 34) heifers were randomly allocated to three intravaginal progesterone‐releasing device (IPRD) treatment groups: (i) standard‐dose IPRD [Cue‐Mate® (CM) 1.56 g; n = 17]; (ii) half‐dose IPRD [0.78 g progesterone (P4); CM 0.78 g; n = 15]; (iii) half‐dose IPRD + 300 IU equine chorionic gonadotrophin at IPRD removal (CM 0.78 g + G; n = 14); (iv) and a control group, 2× PGF [500 μg prostaglandin F (PGF)] on Day ?16 and ?2 (n = 18). Intravaginal progesterone‐releasing device‐treated heifers received 250 μg PGF at IPRD insertion (Day ?10) and IPRD removal (Day ?2) and 1 mg oestradiol benzoate on Day ?10 and ?1. Heifers were managed in a small feedlot and fed a defined ration. Ovarian function was evaluated by ultrasonography and plasma P4 throughout the synchronized and return cycles. Energy balance was evaluated using plasma insulin‐like growth factor 1 (IGF‐I) and glucose concentrations. The impact of environmental stressors was evaluated using plasma cortisol concentration. Heifers that had normal ovarian function had significantly higher IGF‐I concentrations at commencement of the experiment (p = 0.008) and significantly higher plasma glucose concentrations at Day ?2 (p = 0.040) and Day 4 (p = 0.043), than heifers with abnormal ovarian function. There was no difference between the mean pre‐ovulatory cortisol concentrations of heifers that ovulated or did not ovulate. However, heifers that ovulated had higher cortisol concentrations at Day 4 (p = 0.056) and 6 (p = 0.026) after ovulation than heifers that did not ovulate.  相似文献   
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Advanced nitrogen-removal onsite wastewater treatment systems (OWTS) are used to reduce total nitrogen (N) levels in domestic wastewater. Maintaining system performance requires regular monitoring and in situ rapid tests can provide an inexpensive option for assessing treatment performance. We used a portable photometer to measure ammonium and nitrate concentrations in final effluent from 46 advanced N-removal OWTS, sampling each site at least three times in 2017. To assess photometer accuracy, we compared measurements made using the photometer with those determined by standard laboratory methods using linear regression analysis and a two-tailed t test to compare regression parameters to those for a perfect linear relationship (slope?=?1, intercept?=?0). Our results show that photometer-based analysis reliably estimates inorganic N (ammonium and nitrate) concentration in field and laboratory settings. Photometer-based analysis of the sum of inorganic N species also consistently approximated the total N concentration in the final effluent from the systems. A cost-benefit analysis indicated that the photometer is a more cost-effective option than having samples analyzed by commercial environmental testing laboratories after analysis of 8 to 33 samples. A portable photometer can be used to provide reliable, cost-effective measurements of ammonium and nitrate concentrations, and estimates of total N levels in advanced N-removal OWTS effluent. This method can be a viable tool for triaging system performance in the field, helping to identify systems that are not functioning properly and may need to be adjusted or repaired by an operation and maintenance service provider in order to meet treatment standards.  相似文献   
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OBJECTIVE: To compare the anesthetic efficacy and physiologic changes associated with exposure to tricaine methanesulfonate and clove oil (100% eugenol). ANIMALS: 15 adult cultured red pacu (Piaractus brachypomus). PROCEDURE: Fish were exposed to each of 6 anesthetic concentrations in a within-subjects complete crossover design. Stages of anesthesia and recovery were measured, and physiologic data were collected before and during anesthesia. RESULTS: Interval to induction was more rapid and recovery more prolonged in fish exposed to eugenol, compared with those exposed to tricaine methanesulfonate. The margin of safety for eugenol was narrow, because at the highest concentration, most fish required resuscitation. Mixed venous-arterial PO2 consistently decreased with anesthesia, while PCO2 consistently increased with anesthesia in all fish regardless of anesthetic agent. The increase in PCO2 was accompanied by a decrease in pH, presumably secondary to respiratory acidosis. Anesthesia was associated with increased blood glucose, potassium, and sodium concentrations as well as Hct and hemoglobin. Fish anesthetized with eugenol were more likely to react to a hypodermic needle puncture than fish anesthetized with tricaine methanesulfonate. CONCLUSIONS AND CLINICAL RELEVANCE: Anesthesia induced with tricaine methanesulfonate or eugenol contributes to hypoxemia, hypercapnia, respiratory acidosis, and hyperglycemia in red pacu. Similar to tricaine methanesulfonate, eugenol appears to be an effective immobilization compound, but eugenol is characterized by more rapid induction, prolonged recovery, and a narrow margin of safety. Care must be taken when using high concentrations of eugenol for induction, because ventilatory failure may occur rapidly. In addition, analgesic properties of eugenol are unknown.  相似文献   
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Fatal herpesvirus infections were diagnosed in 3 patas monkeys and 1 black and white colobus monkey over a 4-week period. Herpesvirus was isolated from 1 patas monkey and from the black and white colobus monkey. Both isolates had growth characteristics similar to Herpesvirus hominis and Herpesvirus simiae. The isolate from the colobus monkey antigenically appeared to be H simiae or H simiae-like, whereas the isolate from the patas monkey could not be conclusively identified with the antisera used. All affected animals were housed in close proximity to rhesus monkeys, the carrier host of H simiae.  相似文献   
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Computer-automated sperm-head morphometry was used in this study to determine the effects of cryopreservation on red deer sperm-head morphometry. Epididymal sperm samples were collected from 40 mature stags and were divided. One portion was diluted at room temperature in a Tris-citrate egg yolk medium, containing 6% glycerol. A microscope slide was prepared from single extended sperm samples prior to freezing. The remainder of each sample was frozen in nitrogen vapours. After thawing, sperm smears were prepared as described above. All slides were air dried and stained with Hemacolor. The sperm-head dimensions for length, width, area, perimeter and shape factor (length/width), for a minimum of 135 spermatozoa were determined for each slide by means of the Sperm-Class Analyser (SCA). Firstly, our results show that cryopreservation substantially reduced (p < 0.001) sperm motility and plasma membrane and acrosome integrities. In addition, sperm heads were significantly smaller in cryopreserved spermatozoa than in the companion extended samples for area (32.05 microm2 vs 32.56 microm2; p < 0.05), length (8.46 microm vs 8.53 microm; p < 0.0001) and shape factor (1.833 vs 1.849; p < 0.0001) for all stags. These differences were found within 29 of 40 stags (75%) for at least three of the morphometric parameters. The individual variability (CV) of sperm head measurements from extended samples was negatively correlated (p < 0.005) with the per cent of change in sperm head measurements after cryopreservation for area (r = -0.465), width (r = -0.483) and perimeter (r = -0.375). Thus, the lower the sperm head variability in the extended samples, the greater the sperm change as a consequence of the cryopreservation. These results suggest that the variability (heterogeneity) in sperm head dimensions of individual stags may be a good indicator of sperm freezability.  相似文献   
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