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81.
Abstract

Extract

New Zealand is remarkable for the few species of tick that occur in the country and an apparent absence of tick-borne diseases. There is, however, only a lack of reports of locally-acquired infections which indicates tick-borne spotted fever group (SFG) rickettsias, ehrlichias, anaplasmas and bartonellas do not occur in the country (Roberts et al 2001 Roberts, S, Hill, P, Croxson, M, Austin, P, McKay, J and Ellis-Pegler, R. 2001. The evidence for rickettsial disease arising in New Zealand. New Zealand Medical Journal, 114: 372374.  [Google Scholar]). To provide more definitive information, we conducted a PCR survey on ticks from New Zealand.  相似文献   
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83.
Extract

Pathological changes and immunohistochemical (IHC) examination for porcine circovirus-2 (PCV-2) in nine weaner pigs from a property with PMWS are reported. The pigs were in moderate to poor body condition, and several had diarrhoea and noisy respiration. The outstanding pathological changes related to microscopic lesions in lymphoid tissues, including lymph nodes, palatine tonsils, Peyer's patches, peribronchial lymphoid aggregates and spleen. While there was variability of expression of change between and within cases, the main features of lesions could be summarised as depletion of lymphoid cells, infiltration of histiocytes (often syncytial), and the presence of botryoid intra-cytoplasmic inclusion bodies in macrophages. The changes in lymphoid tissue were typical of those described in PMWS. Also characteristic of this syndrome were histiocyte-dominated cellular inflammatory infiltrates in kidney, liver and lung. There was strong correlation between IHC positivity for PCV-2 and the lesions in lymphoid, pulmonary and renal tissues. Concurrent diseases that are probably promoted by immune suppression may complicate the diagnosis of PMWS. In the present cases, salmonellosis, attaching and effacing Escherichia coli infections, and secondary bacterial bronchopneumonia were identified.  相似文献   
84.
Organisms in polluted environments are typically exposed to a complex mixture of chemical contaminants. The great concern about the health of aquatic ecosystems has led to the increased use of biomarkers over the past years. The aim of this work was to review the papers published from 2000 to 2015, which used biomarkers to assess the health of aquatic ecosystems in Brazil. A research resulted in 99 eligible papers. More than 80% of studies were conducted in the states of São Paulo and Rio Grande do Sul. Approximately 63% of studies used fish as bioindicator, whereas the micronucleus test and biochemical analyses were the most used biomarkers. A multibiomarker approach was used by 60.6% of studies, while 39.4% used one single biomarker. Furthermore, 68% were field studies and more than 75% of these used control animals sampled at reference sites. A relationship between the biomarker responses and pollution was reported by 87% of studies; however, 43.4% of studies analyzed only one sampling period, limiting comparisons and comprehension about possible seasonal variations. This review evidenced some weak points in studies using biomarkers in Brazil, especially related to the lack of studies in two important biomes (the Pantanal and the Amazon Rainforest) and experimental designs (small sample size, sampling in one single period, use of one single biomarker). Thus, future studies should consider mainly the use of multiple biomarkers, greater sample size, seasonal sampling and water physicochemical parameters to better diagnose the health of aquatic ecosystems.  相似文献   
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Lactobacillus buchneri was investigated as a silage inoculant and as a probiotic on feed intake, apparent digestibility, and ruminal fermentation and microbiology in wethers fed low‐dry‐matter (DM) whole‐crop maize silage. Maize forage (279 g/kg DM) was ensiled without inoculant (untreated) and with L. buchneri CNCM I‐4323 at 1 × 10cfu/g fresh forage (inoculated). Six cannulated wethers were arranged in a double 3 × 3 Latin square and assigned to one of three diets: (i) untreated maize silage (untreated), (ii) inoculated maize silage (inoculated), and (iii) untreated maize silage with a daily dose of L. buchneri (1 × 10cfu/g supplied silage) injected directly into the rumen (LB‐probiotic). Wethers fed the inoculated diet had a higher (= .050) DM intake (1.30% body weight [BW]) than wethers fed untreated and LB‐probiotic diets (1.17% and 1.18% BW respectively). The relative proportion of Ruminococcus flavefaciens (proportion of total estimated rumen bacterial 16S rDNA) in the rumen of wethers fed inoculated and LB‐probiotic diets (both 0.42%) tended (= .098) to be lower than in the untreated diet (0.83%). Lactobacillus buchneri as a silage inoculant or as a probiotic had little effect on the variables measured in wethers.  相似文献   
88.
It has been evident the improvement of in vitro embryo production (IVEP) in dairy cows. Nevertheless, it is known that differences in the number and quality of oocytes between taurine and zebu females impact the efficiency and economic viability of IVEP. As the insulin‐like growth factor (IGF) system is related to follicular and oocyte development, we aimed to quantify mRNA abundance of IGF system members and pregnancy‐associated plasma protein‐A (PAPPA) in the cumulus–oocyte complexes (COCs) of Gir, 1/2 Holstein × 1/2 Gir and Holstein cows. Four pools of 30 immature COCs from Gir, 1/2 Holstein × 1/2 Gir and Holstein cows were obtained by ovum pickup (OPU), and the oocytes and cumulus cells (CC) were mechanically separated and stored at ?80°C. Total RNA was extracted from pools of 30 oocytes and their respective CC. Expression of target genes was assessed by real‐time RT‐PCR. In oocytes, the abundance of IGFR1 mRNA was higher (< .05) in Gir cows compared with the other breeds. In contrast, in CC, mRNA encoding IGF2 (< .05), IGFR2 (< .05) and IGFBP4 (< .01) was higher in Holstein donors compared with Gir and 1/2 Holstein × 1/2 Gir cows. Additionally, the abundance of PAPPA mRNA was higher in oocytes (< .001) and CC (< .01) in Gir and 1/2 Holstein × 1/2 Gir cows compared with the Holstein donors. In conclusion, the higher abundance of PAPPA mRNA in the oocytes and CC from Gir and cross‐breed donors combined with the low expression of IGFBP4 in the CC suggests an enhancement of the bioavailability of IGF‐free when compared with Holstein COCs.  相似文献   
89.
Besnoitia sp. are apicomplexan coccidian parasites affecting several species of mammals and cold-blooded animals in several countries. Besnoitia sp. tissue cysts were seen in several tissues of five rabbits from a rabbit breeder in La Plata, Argentina. Bradyzoites released from macroscopic tissue cysts were inoculated onto bovine monocytes, and into interferon gamma gene knockout (KO) mice. Besnoitia sp. tachyzoites were seen in the peritoneal exudate of KO mice on day 10 pi and these tachyzoites were infective to other KO mice. Tachyzoites grown in cell culture were infective to gerbils (Meriones unguiculatus). This is the first report of Besnoitia sp. infection in any host in Argentina.  相似文献   
90.
The aim of this study was to determine the effects of gonadotrophin releasing hormone (GnRH) administration on the plasma concentrations of reproductive hormones in intact and ovariectomized (OVX) bitches. Therefore, blood samples were collected at multiple times before and after the administration of 10 microg/kg GnRH (Fertagyl)) for the determination of the plasma concentrations of luteinizing hormone (LH), oestradiol, progesterone and testosterone in six anoestrus and in six OVX bitches. The mean plasma LH concentrations before and 60 min after GnRH administration were significantly lower in the anoestrous bitches than in the OVX bitches. In both groups GnRH administration resulted in a significant increase in the plasma LH concentration. The highest plasma LH concentrations were found at 10 min after GnRH administration and these values did not differ significantly between the two groups. Only in the anoestrous bitches a significant increase in plasma oestradiol concentrations was found after GnRH administration and these values were significantly higher than those in the OVX bitches. The plasma concentrations of progesterone and testosterone were low (close to or below the limit of quantitation) both before and after GnRH administration and the differences between anoestrous and OVX bitches were not significant. It can be concluded that (i) basal plasma LH concentration is significantly higher in OVX bitches than in anoestrous bitches, (ii) plasma LH concentration increases after GnRH administration in both anoestrous and OVX bitches, (iii) GnRH administration causes a significant rise in plasma oestradiol concentration only if ovarian tissue is present and (iv) measurement of plasma progesterone and testosterone concentrations before and after GnRH administration does not aid in distinguishing between anoestrous and OVX bitches. The results of this study may provide a basis for the diagnosis of remnant ovarian tissue and verification of neuter status in the bitch.  相似文献   
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