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991.
Bluetongue (BT) is an important disease of ruminants which exhibits its most severe clinical signs on cattle and especially on certain breeds of sheep. The known vectors of BT are small insects of the genus Culicoides (Diptera; Ceratopogonidae). Two species from this genus – Culicoides imicola and Culicoides obsoletus – play the major role in the transmission of the disease in Europe. Several prophylactic methods are used to avoid transmission; however, an easy and cost-effective preventive technique would be very useful for the control of the Culicoides populations near the animals. In the present study, the insecticide effect of cypermethrin treated nets on a Culicoides population was evaluated. A polyethylene net sprayed with 1 L cypermethrin solution (1%) surrounding a UV light suction trap was placed at a cattle farm in Majorca (Balearic Islands). Collections of Culicoides and other fauna from the trap and floor around the net were compared with a control. Results showed no significant differences in the collection of Culicoides midges between the insecticide-treated net and the control. However, significant differences were observed in the collection of the non-target fauna between the treated net and the control, indicating that the dose used in the present trial was enough to kill most of the arthropods that contacted the net. The reasons for these equivocal findings and means to improve this technique for the control of Culicoides midges are discussed. 相似文献
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994.
JM Baldrighi MF Sá Filho EOS Batista RNVR Lopes JA Visintin PS Baruselli MEOA Assumpção 《Reproduction in domestic animals》2014,49(6):1015-1020
This study was performed to evaluate plasma concentrations of anti‐Mullerian hormone (AMH) and the ovarian antral follicle population (AFP) in different genetic groups. Cyclic heifers (13 Bubalus bubalis [Murrah]; 15 Bos taurus [Holstein] and 10 Bos indicus [Gyr]) were maintained under the same management and were synchronized with two doses of 150 μg IM d‐cloprostenol administered 14 days apart. After the second d‐cloprostenol treatment, heifers had their ovaries scanned daily by ultrasound to define the day of ovulation. On the same day, the AFP was determined and a plasma sample was collected to measure AMH. Murrah heifers had less AFP (25.6 ± 2.1 follicles; p = 0.01) and plasma AMH concentration (0.18 ± 0.03 ng/ml; p < 0.001) than Gyr (60.0 ± 12.2 follicles and 0.60 ± 0.12 ng/ml of AMH); however, data were similar when compared to Holstein (35.9 ± 6.8 follicles and 0.24 ± 0.06 ng/ml of AMH) heifers. Regardless of genetic background, there was a positive relationship between the AFP and plasmatic AMH concentration (Murrah [r = 0.62; p < 0.01], Holstein [r = 0.66; p < 0.001] and Gyr [r = 0.88; p < 0.001]). Also, when heifers were classified according to high‐ or low‐AMH concentration based on the average within each genetic group, high‐AMH heifers had greater (p < 0.0001) AFP than low‐AMH heifers. In conclusion, both Murrah and Holstein heifers presented lower plasma AMH concentration and AFP when compared to Gyr. 相似文献
995.
Rosana C. S. Ogoshi Márcio G. Zangeronimo Jéssica S. Dos Reis Janine França João P. F. Santos Carolina P. Pires Ana F. Chizzotti Adriano C. Costa Lívia G. Ferreira Flávia M. O. B. Saad 《Animal Science Journal》2014,85(5):555-561
This study evaluated the effects of adding an acidifying agent based on phosphoric acid (A), a yeast extract from a specific strain (Saccharomyces cerevisiae) (Y) and the combination of these two additives in food for adult cats. A test was conducted with 24 animals (mean 3.5 years old), mixed breed, weighing 3.72 ± 0.74 kg, kept in individual metabolic cages and distributed in a completely randomized design with a 2 × 2 factorial design (with or without A 0.6% of dry matter, with or without Y 1.5% of dry matter) totalling four treatments and six replicates of each condition. The experimental period was 15 days. The A or the Y reduced (P < 0.01) the dry matter intake, but the effect was not observed when they were associated. The association improved (P < 0.05) the digestibility of dry matter and ashes. The A reduced urine pH (P = 0.05) regardless of the presence of the Y. There was no effect (P > 0.09) on other parameters evaluated. Results of this study show that the isolated use of 0.6% A or 1.5% Y in diets for cats is not recommended. However, the association of these two additives was beneficial in increasing nutrient digestibility. 相似文献
996.
通过浙江某港口底泥疏浚物的水相和固相分别对不同鱼类、甲壳类、贝类的毒性实验,进而评价疏浚物海洋倾倒对泻洋生物影响程度。结果显示,疏浚物水相对黑鲷(Sparus macrocephaius),鲻鱼(Mugil cephalus L.)和长额刺糠虾(Acanthomysis longirostris li)有不同的致死率,黑鲷和鲻鱼的96h死亡率与对照组差异不显著;糠虾的96h死亡率与对照组有明显差异,其中耐污力由强到弱为鲻鱼〉黑鲷〉长额刺糠虾;疏浚物固相对泥蚶(Tegillarca granosa)和缢蛏(Sinonovacula constricta)的10d致死率与对照组差异也不显著,泥蚶的耐污力大于缢蛏。由此可知,浙江某港口底泥疏浚物海洋倾倒会对海洋生物产生一定的毒害效应,其中疏浚物对鱼虾类的影响较大,对贝类的影响较小,表明疏浚物的影响程度因种类的不同而存在较大的差异。 相似文献
997.
黑曲霉Uγ-2(Aspergillus niger Uγ-2)产菊粉酶的研究 总被引:1,自引:0,他引:1
研究了黑曲霉Uγ-2的产酶进程及其产酶条件,结果表明:在1g/mL^-1菊芋汁中添加30mg/mL^-1的牛肉膏,调节初始pH6.0,摇瓶转速为180r/min^-1,30度条件下发酵最高酶活力为180.33umol/min^-1,mL^-1。发酵初期产酶速率较快,pH下降速度快,在发酵进行到72-96h期间,出现产酶的迟缓期,此时发酵液的pH为4.62-4.38,以后菊粉酶活力明显上升,在192h时菊粉酶活力达到最高值,发酵液pH降到最低点,在发酵进程中,发酵液可溶性蛋白出现2个高峰,72h出现第一高峰,与菊粉酶活力比较表明此时主要是杂蛋白产生所致;在192h时出现的第二高峰与菊粉酶活力同步,说明主要是菊粉酶产生,与生物量的变化曲线比较,尽管在发酵初期产酶速率较快,但菊粉酶在发酵液中大量积累出现在120h后(对数增长期的后期)。γγγγγ 相似文献
998.
根据林区育苗生产的需要,本文对塑料大棚棚型的选择,材料及结构尺寸的确定进行了设计计算。并对试制生产的棚体结构进行了野外生产考验。认为该设计方案是合理的,其强度、刚度及稳定性均满足要求。 相似文献
999.
Benedito Donizete Menozzi Giselle Souza da Paz Laís Moraes Paiz Hans Garcia Garces Brunna Mayla Vasconcelos Adorno Fernando Almeida‐Silva Rosely Maria Zancope Oliveira Virgínia Bodelo Richini‐Pereira Jssica Luana Chechi Eduardo Bagagli Sandra de Moraes Gimenes Bosco Helio Langoni 《Zoonoses and public health》2020,67(2):138-147
Bats are essential to the global ecosystem, but their ability to harbour a range of pathogens has been widely discussed, as well as their role in the emergence and re‐emergence of infectious diseases. This paper describes the first report of coinfection by two zoonotic agents, rabies virus (RABV) and the fungus Histoplasma suramericanum in a bat. The bat was from the Molossus molossus species, and it was found during the daytime in the hallway of a public psychiatric hospital in a municipality in São Paulo State, southeastern Brazil. RABV infection was diagnosed by the direct fluorescent antibody test and mouse inoculation test. The fungus was isolated by in vitro culture. Both diagnoses were confirmed by molecular techniques. Phylogenetic analysis showed that the fungus isolate had proximity to H. suramericanum in the Lam B clade, while the RABV isolate was characterized in the Lasiurus cinereus lineage. Since the M. molossus bat was found in a peri‐urban transition area (urban/peri‐urban), the possibility of cross‐species transmission of this RABV lineage becomes more plausible, considering that this scenario may provide shelter for both M. molossus and L. cinereus. These are relevant findings since there has been an increase in bat populations in urban and peri‐urban areas, particularly due to environmental modifications and anthropogenic impacts on their habitat. Thus, the detection of two zoonotic agents in a bat found in a public hospital should raise awareness regarding the importance of systematic surveillance actions directed towards bats in urban areas. 相似文献
1000.
Nídia Sequeira Trovo Guadalupe Ayora Talavera Martha I. Nelson Juan Diego Perez de la Rosa 《Zoonoses and public health》2020,67(3):318-323
Highly pathogenic H7N3 influenza A viruses have persisted in poultry in Mexico since 2012, diversifying into multiple lineages that have spread to three Mexican states, as of 2016. The H7N3 viruses segregate into three distinct clades that are geographically structured. All 2016 viruses are resistant to adamantane antiviral drugs and have an extended 24‐nucleotide insertion at the HA cleavage site that was acquired from host 28S ribosomal RNA. 相似文献