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61.
Between late December 1999 and late April 2000, three locally bred Friesian calves (ageing 25, 28 and 35 days) in a dairy farm, at Al‐Ahsa locality of the eastern region of Saudi Arabia showed dullness and inappetence. Their rectal temperatures ranged between 41 and 41.5°C. One to 2 days later and onwards, the calves showed lacrimation, nasal discharge, salivation, oedema of the head, conjunctivitis, exo‐ophthalmia and corneal opacity. One calf showed diarrhoea. The superficial lymph nodes were oedematous and swollen. The calves died after 7, 5 and 8 days, respectively, following the onset of the disease. Calves and rabbits were experimentally infected with materials from the naturally infected calves. The rabbits showed fever, mild conjunctivitis and one rabbit showed wet faeces. The experimentally inoculated calves showed rise in temperature and mild symptoms but none of them died. The virus from the naturally infected calves and from the experimentally infected rabbits was identified as malignant catarrhal fever (MCF) virus using both the complement fixation test and the fluorescent antibody test, employing a reference anti‐serum against the WC 11 strain of MCF virus. Serological survey for MCF antibodies in cattle, sheep and goats from the affected farm revealed that 54% of the examined animals were positive. The situation of MCF in Saudi Arabia was discussed in relation to sheep and wild game. This paper constitutes the first report of MCF in Saudi Arabia and the Gulf region.  相似文献   
62.
The Greater cane rat (GCR, Thyronomys swinderianus) is a precocial rodent predominantly found within Africa. Economic and scientific interests have led to several research efforts towards the domestication and better understanding of the biology and development of this rodent. Despite these efforts, information on the pre‐natal development of this rodent is currently lacking. This study characterises distinct developmental milestones including skin pigmentation, emergence and distributions of hairs, calvarium consistency, teeth eruption, development of appendages, sensory organs and external genitalia in the pre‐natal GCR and assesses quantitative body parameters, that is body weight, body and crown–rump lengths across its entire gestation length (gestation days [GDs] 10‐140). Using these external features, we provide baseline reference ontogenetic scales for GCR embryos and fetuses, employable for stage, age and sex estimation of the pre‐natal GCR in future studies. We observed that the first evidence of an embryo was not seen before the end of the first trimester (GD50) and that the late second trimester (GD80‐GD100) marks the transition from embryogenesis to fetogenesis in the GCR. As both events occur at a much later developmental time point when compared to precocial non‐rodents including human, sheep and pig and slightly later when compared to other precocial rodents such as guinea pig, our data provide first indication that the pre‐natal GCR development might be associated with a reproductive delay. Together, this study expands our knowledge of the development and biology of the GCR, which will improve reproductive and breeding management, and native species conservation of this hystricomorph mammal.  相似文献   
63.
Osteopontin gene is regarded as a plausible candidate in mammary gland differentiation and development, expressed by variety of cells, tissues, and biological fluids including milk. The current study was performed in two phases. In the first phase, Osteopontin gene polymorphisms were identified and associated with milk composition such as ash, milk fat, SNF, lactose, and protein. In the second phase, milk samples from five healthy mastitis-free Nili Ravi buffaloes were analyzed for expression of Osteopontin gene at transition (day 15), mid (day 90), and end (day 250) stage of their second lactation. Briefly, blood samples were collected from Nili Ravi buffalo to isolate the genomic DNA, specific primers were designed for PCR amplification. The amplified PCR products were sequenced bi-directionally. Six polymorphisms were identified in the coding region and four in the intronic region of the gene. The results showed that SNP g.38329758 T > C causing substitution of valine to alanine (V127A) was associated with high milk protein. For mRNA expression analysis, somatic cells were separated from milk samples for RNA isolation. Analysis of differential gene expression data has permitted us to illustrate the expression pattern of osteopontin gene in lactating buffalo. The Osteopontin gene was found to be transcribed among all three lactation stages, but expression was observed with the highest value (fold change) in peak lactation and remained elevated till the end of lactation. Identified gene marker may be helpful for the prediction of superior animal for selection. The presented study also gave an insight into the genetic screening and lactation biology of riverine buffalo, offering direction for future research in lactating buffalo.  相似文献   
64.
The effects of sun-drying cowpea seeds for three hours on cement (CS), wood (WS), and corrugated iron sheet (CIS) surfaces and packaging separately in polyethene and jute bags were studied. Moisture-gain, and resistance to insect and mold damage were monitored monthly for six months, while proximate analyses on day zero and at the 6th month were conducted. Results showed that the three-hour sun-drying of cowpea seeds on reflective surfaces (CIS and CS) enhanced the rate of moisture-reabsorption during storage and consequently, the degree of mold and insect damage irrespective of the packaging material employed. Crude fat, fiber and ash contents, unlike protein and moisture contents, remained virtually constant (p < or = 0.05). In this study, the wood surface and polyethene bag were the most preferred treatments to store sun-dried cowpea seeds for about 5.7 months.  相似文献   
65.
66.
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   
67.
The present study was undertaken to evaluate the effects of feeding the male mice with miso that was prepared with a mixture of microbial starters on the level of lipid peroxidation as a marker of oxidative stress, antioxidant power of hepatocytes, the enzymatic and non-enzymatic antioxidant. The starters that were used in the preparation of miso were Aspergillus oryzae and Pleurotus ostreaus or A. oryzae and Bacillus subtilis. The miso that was prepared with A. oryzae and Bacillus subtilis has more effect on suppressing the oxidative stress and enhancement of endogenous antioxidant of hepatocytes and renal tissue of mice.  相似文献   
68.
细粒棘球蚴-原头蚴体外培养成囊模型的建立   总被引:1,自引:0,他引:1  
建立原头蚴体外成囊发育的技术方法,为包虫病研究提供实验材料。在CO2培养箱中37℃条件下,单相培养体系中体外培养原头蚴,并用显微镜定期观察其大小及形态变化。结果发现:第10天原头蚴开始向囊发育;在第35~40天出现肉眼可见的囊,存活时间达100 d,最大囊可达2 mm,原头蚴成囊率达90%。  相似文献   
69.
This article describes the development of environmentally friendly nano-emulsion system for water-soluble herbicide application. Pseudoternary phase diagrams were established in the emulsion system of fatty acid methyl esters (FAMEs)/alkylpolyglucosides (APG) and/or 3-(3-hydroxypropyl)-heptamethyltrisiloxane (organosilicone)/water encompassed with 41% (w/w) glyphosate isopropylamine (IPA) as herbicide active. Pre-formulations were selected from isotropic (L) region in the phase diagrams and their emulsion system characteristics were determined. The microemulsion systems were chosen and then dispersed into water using low-energy stirring method (200 rpm for 5 min). Oil-in-water (O/W) nano-emulsions were formed with particle sizes of diameter less than 200 nm. The nano-emulsion systems showed significantly lower surface tension than a commercial formulation (Roundup®). In the biological application study, treatments of nano-emulsion formulations and Roundup® were applied on narrow-leaved weed Eleusine indica. Multiple doses of glyphosate IPA of the treatments were applied for the construction of dose-response curves for determination of effective dose (ED50). The nano-emulsion formulation showed lower ED50 was 0.40 kg a.e./ha in controlling the weed than Roundup® was 0.48 kg a.e./ha. This finding suggested that the possibility of using nano-emulsion system to increase penetration and uptake of glyphosate IPA.  相似文献   
70.
Between late December 1999 and late April 2000, three locally bred Friesian calves (ageing 25, 28 and 35 days) in a dairy farm, at Al-Ahsa locality of the eastern region of Saudi Arabia showed dullness and inappetence. Their rectal temperatures ranged between 41 and 41.5 degrees C. One to 2 days later and onwards, the calves showed lacrimation, nasal discharge, salivation, oedema of the head, conjunctivitis, exo-ophthalmia and corneal opacity. One calf showed diarrhoea. The superficial lymph nodes were oedematous and swollen. The calves died after 7, 5 and 8 days, respectively, following the onset of the disease. Calves and rabbits were experimentally infected with materials from the naturally infected calves. The rabbits showed fever, mild conjunctivitis and one rabbit showed wet faeces. The experimentally inoculated calves showed rise in temperature and mild symptoms but none of them died. The virus from the naturally infected calves and from the experimentally infected rabbits was identified as malignant catarrhal fever (MCF) virus using both the complement fixation test and the fluorescent antibody test, employing a reference anti-serum against the WC 11 strain of MCF virus. Serological survey for MCF antibodies in cattle, sheep and goats from the affected farm revealed that 54% of the examined animals were positive. The situation of MCF in Saudi Arabia was discussed in relation to sheep and wild game. This paper constitutes the first report of MCF in Saudi Arabia and the Gulf region.  相似文献   
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