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21.
The present work aimed to describe the normal computed tomography (CT) and cross‐sectional anatomy of the nasal and paranasal sinuses in sheep and to correlate these features with the relevant clinical practices. Twenty apparent healthy heads of Egyptian native breed of sheep (Baladi sheep) of both sexes were used for studying these sinuses. CT images and their closely identical cross sections of the same head were selected and serially labelled in a progression from the rostral nasal region to the caudal aspect of the head using cheek teeth as landmarks. The current investigation reported seven sinuses in sheep, including maxillary, frontal, lacrimal and sphenoidal as paranasal, as well as dorsal and middle conchal and ethmoidal as nasal with unnoticeable palatine and ventral nasal conchal sinuses. The boundaries, extension, structure and communications of these sinuses were fully described. The current study provided anatomical guidelines for surgical interference in the frontal and maxillary sinuses during trephination, dehorning and sinuscopy. Also, an acceptable anatomical explanation was reported in this study for the high incidence of maxillary sinusitis than other sinuses. CT and cross‐sectional anatomy could be used as helpful database for diagnosis and clinical interference of the nasal and paranasal sinuses in sheep.  相似文献   
22.
Heat stress at reproductive stages of cotton crop is the main cause for instability in yield than other abiotic stresses of crops. An experiment was conducted to observe the impacts of heat stress at squaring and flowering stages of cotton and potential of exogenously applied ascorbic acid to alleviate this stress. The experiment was planted for two consecutive years, that is 2013 and 2014, in randomized complete block design with split plot arrangement having three replications. Treatments were comprised of heat stress in main plots, viz. H0 = no heat imposition; H1 = heat imposition at square initiation; H2 = heat imposition at flower initiation and foliar‐applied ascorbic acid in subplots, viz. A0 = control or water spray; A1 = 20 mg/L; A2 = 40 mg/L; and A3 = 60 mg/L. Results showed that heat stress badly affected plant water relations (relative water contents and osmotic potential), total chlorophyll contents and activities of antioxidant enzymes that led to a corresponding decrease in seed cotton yield. Foliar application of ascorbic acid (40–60 mg/L) ameliorated adverse effects of heat and thus helped the crop to improve its water relations, stay green and antioxidant enzymes resulting into better crop yield.  相似文献   
23.
The diameter of the preovulatory follicle (POF) and its effects on subsequent corpus luteum (CL) size and conception were studied in 38 lactating indigenous cycling buffaloes in the Mymensingh district of Bangladesh. Body condition score (BCS) at estrus was estimated for the buffaloes. The buffaloes were synchronized with two injections of a synthetic analogue of PGF2α administered 11 days apart. Transrectal ultrasonography was carried out at estrus and on days 5, 9, 12 and 16 post ovulation to determine the POF and successive CL size. Pregnancy was confirmed by ultrasound examination on day 40-45 post ovulation. Twenty one (55.3%) buffaloes were diagnosed as pregnant. The conception rates of thin (BCS ≤2.0), good (BCS 2.5-3.5) and fat (BCS glt;3.5) buffaloes were 7.7, 88.2 and 62.5% (χ2 = 19.54; P<0.05), respectively. The mean diameter of the POF at estrus was larger (P<0.01) in buffaloes that ultimately were diagnosed as pregnant compared with their nonpregnant counterparts (13.7 ± 0.3 vs. 11.2 ± 0.5 mm, respectively). The conception rates of buffaloes having small (9 to ≤ 12 mm), medium (>12 to ≤14 mm) and large (>14 to 16 mm) POFs at estrus were 9.1, 70.0 and 85.7% (χ2 = 13.87, P<0.01), respectively. On day 5 post ovulation, CL size was positively correlated (CL: r=.74, P<0.01) with POF diameter. Retrospective analysis revealed that on day 5 post ovulation, the pregnant buffaloes had higher (P<0.01) post ovulation CL sizes than their nonpregnant counterparts (15.6 vs. 11.8 mm). Similarly, on day 9 post ovulation, the difference in CL size (14.3 vs. 13.6 mm) between pregnant and nonpregnant buffaloes was significant (P<0.05). In conclusion, the diameter of the POF in buffaloes has a positive impact on the size of the post ovulation CL and conception.  相似文献   
24.
Echinococcosis is an important medical, veterinary and economic concern in India. Ten cysts were randomly selected from each intermediate host species (cattle, buffalo, sheep, goat and pigs). Either the germinal layer (sterile cysts) or protoscoleces (fertile cysts) were collected for molecular characterization. A 434 base pair fragment of the mitochondrial cytochrome oxidase-1 gene was amplified using PCR from each isolate. Ten representative samples (2 from each intermediate host species) were sequenced in both the directions from which readable sequences were obtained from nine for phylogenetic analysis (NCBI, Blast). Phylogenetic analysis of cytochrome oxidase I gene revealed that seven (77.7%) isolates, from cattle (2), pigs (2), buffaloes (1) and goat (2) were clustered with the Indian Buffalo (G3) strain of Echinococcus granulosus, while two (22.2%) isolates from sheep were clustered with the sheep strain (G1) of E. granulosus. Phylogenetic analysis of the cytochrome oxidase-1 gene revealed that the buffalo strain (G3) and common sheep strain (G1) are cycling among livestock in north India and that these strains are highly adapted to cattle, buffalo, sheep, goats and pigs.  相似文献   
25.
The study was carried out to detect Theileria annulata, the causative agent of theileriosis, and Babesia bovis, the causative agent for babesiosis, in Friesian cattle by PCR and conventional blood smear examination. One hundred blood samples obtained from diseased Friesian cattle kept on private livestock farms at Pattoki, District Kasur, Pakistan were collected in addition to 20 blood samples obtained from non-diseased animals. The disease manifestations observed clinically included high fever, swelling of sub mandibular and sub scapular lymph nodes, weakness, increased respiration and pulse, anorexia, loss of condition and rough hair coat. Neurologic sign of in coordination was also seen in weak animals. Signs of lacrimation, pale conjunctiva, diarrhoea, dyspnea and frothy nasal discharge were observed in only one animal. Clinically nine animals showed signs of haemoglobinuria. Diagnosis of bovine theileria and babesia species was based on finding many intraerythrocytic piroplasms of both blood protozoa with clinical signs associated with anaemia, lymph node hyperplasia and haemoglobinuria. One hundred samples of ticks were also collected for identification of vector. Results showed that the prevalence of Hyalomma tick was highest (15%) followed by Boophilus (12%), Haemaphysalis (5%) and Rhipicephalus (3%). The blood smear examination showed 21% (21/100) samples positive for blood parasites out of which 66.6% (14/ 21) samples were positive for theileriosis while 42.8% (9/21) were positive for babesiosis. It was also recorded that 66.66% (6/9) samples were positive for B.bigemina while 33.33% (3/9) were positive for B.bovis. The results showed that 60% (60/100) samples were positive for blood parasites by PCR test. Out of these 60% (36/60) were positive for T.annulata while 33.33% (20/60) were positive for babesia. The specificity and sensitivity of PCR test was higher than blood smear examination. The blood parameters in haemoparasites infection were also analyzed and the results showed significant decrease in total erythrocyte count and haemoglobin while MCV, MCH values increased and MCHC was slightly less than normal indicating macrocytic hypochromic anaemia.  相似文献   
26.
A full-length cDNA of a glutathione S-transferase (GST) was cloned from a cDNA library of the local Egyptian cattle tick Boophilus annulatus. The 672 bp cloned fragment was sequenced and showed an open reading frame encoding a protein of 223 amino acids. Comparison of the deduced amino acid sequence with GSTs from other species revealed that the sequence is closely related to the mammalian mu-class GST. The cloned gene was expressed in E. coli under T7 promotor of pET-30b vector, and purified under native conditions. The purified enzyme appeared as a single band on 12% SDS-PAGE and has a molecular weight of 30.8 kDa including the histidine tag of the vector. The purified enzyme was assayed upon the chromogenic substrate 1-chloro-2,4-dinitrobenzene (CDNB) and the recombinant enzyme showed high level of activity even in the presence of the beta-galactosidase region on its 5' end and showed maximum activity at pH 7.5. The Km values for CDNB and GSH were 0.57 and 0.79 mM, respectively. The over expressed rBaGST showed high activity toward CDNB (121 units/mg protein) and less toward DCNB (29.3 units/mg protein). rBaGST exhibited peroxidatic activity on cumene hydroperoxide sharing this property with GSTs belonging to the GST alpha class. I50 values for cibacron blue and bromosulfophthalein were 0.22 and 8.45 microM, respectively, sharing this property with the mammalian GSTmu class. Immunoblotting revealed the presence of the GST molecule in B. annulatus protein extracts; whole tick, larvae, gut, salivary gland and ovary. Homologues to the GSTmu were also detected in other tick species as Hyalomma dromedarii and Rhipicephalus sp. while in Ornithodoros moubata, GSTmu homologue could not be detected.  相似文献   
27.
Teleost fish have developed their own specific adaptive mechanism, both behavioral and physiological, to maintain homeostasis in response to unfavorable temperatures. Therefore, this study was aimed at assessing the critical thermal maxima (CTMax), critical thermal minima (CTMin), and oxygen consumption rate of Anabas testudineus (17.03 ± 1.2 g) after acclimating to three preset temperatures (25, 30, and 35°C) for 30 days. The CTMax and CTMin were 40.15, 41.40, 41.88°C and 12.43, 13.06, 13.94°C, respectively, and were significantly different (P < 0.05). The thermal tolerance polygon for the specified temperatures was 278.30°C2. The oxygen consumption rate (117.03, 125.70, 198.48 mg O2 kg−1 h−1, respectively) increased significantly (P < 0.05) with increasing acclimation temperatures. The overall results indicate that the thermal tolerance and oxygen consumption of A. testudineus are dependent on acclimation.  相似文献   
28.
We focused on key aspects of forest governance for biodiver- sity conservation in implementing new climate change policies. The national forest institutions must be adaptive to identify the existing pitfalls of prior conservation policies to take advantage of new climate change policies. Strengthening roles and technical capacity of national institutions for systematic biodiversity monitoring and carbon stock assessment is required in developing and least developed countries. Community participation needs careful analysis to ensure equitable ac- cess of particular social groups to local decision-making processes and to sustain optional livelihoods. The livelihood options around forest reserves or protected areas must be taken into account to enhance forest-based adaptation.  相似文献   
29.
The purpose of this study was to describe normal magnetic resonance imaging and computed tomographic anatomy of pastern and coffin joints in Egyptian buffalo using cadaveric distal limbs. This study was achieved using twelve fresh cadaveric distal limbs from adult healthy buffaloes of both sexes. These cadaveric limbs were scanned using a 1 Tesla MRI scanner and CT scanner, injected with red latex, frozen at −20°C for 1 week, and then sectioned into sagittal, dorsal and transverse slices. The obtained MR and CT images were selected to be matched with their corresponding anatomical cross-sections for identification and evaluation of the clinically correlated anatomical structures of the pastern and coffin joints. The difference in signal intensities on CT and MRI scans amongst the tissues allowed clear differentiation of major bone and soft tissue structures of the pastern and coffin joints. CT provided a high spatial resolution of bone and soft tissue structures, however, MRI allowed a better and higher resolution and definition between soft tissues. The current study provided a normal CT and MRI anatomic reference which could help veterinary clinicians for interpretation and diagnosis of the clinically affected pastern and coffin joints in buffalo.  相似文献   
30.
Coastal shrimp (Penaeus monodon) aquaculture in Bangladesh is mostly practiced in a special type of field/pond situated by the side of a river -- called a Gher -- that is used to cultivate rice in winter and shrimp in summer. Ghers of different sizes are managed in different ways. In order to understand the effects of Gher size and their corresponding management practices on the production and economic returns of shrimp farming, we conducted an on-farm study in three small (1–5 ha), three medium (6–10 ha) and three large (>10 ha) Ghers located in the coastal Southwest region of Bangladesh. The mean harvest weight of shrimp was similar in all Ghers, but survival rates were higher in the small (50%) and medium (37%) ones than in the large (18%) ones. The high mortality in the large units led to a production that was lower than one-half of that in the small Ghers (about 80 and 200 kg/ha, respectively). The total variable costs per unit area were similar in all Ghers, but the importance of different items varied with Gher size. In the small Ghers, there are relatively high investments on inputs and labor. This expenditure results in lower shrimp mortality and higher production, which in turn results in gross returns that are larger than the total costs -- hence, a positive and high net return. In large Ghers, the fixed costs are larger than in the small ones simply because of the size of the pond. Variable costs include higher investments in post-larvae and labor than in small Ghers, and lower inputs applied only at pond preparation. This results in higher shrimp mortality and lower production, which in turn results in gross returns that are smaller than the total costs -- hence, a negative or low net return. These findings have positive implications for the future policy formulation of coastal shrimp aquaculture in Bangladesh.  相似文献   
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