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101.
An outbreak of bluetongue and the first isolation of the virus in the Sudan are reported. The disease occurred in sheep stressed by walking for five days when biting arthropods were prevalent. Estimates of the morbidity and mortality rates ranged from about 30 per cent and 2 per cent respectively in adult sheep to around 80 per cent and 100 per cent respectively in lambs. The virus was isolated by the inoculation of suckling mice and embryonated eggs with whole blood from febrile sheep. In a gel precipitation test it reacted with specific antiserum to type 10 BT8 strain. No other agent was isolated. Given the relatively mild nature of bluetongue in indigenous sheep, it is believed that the long walking stress coupled with exposure to sunlight might have aggravated the severity of the disease in this particular outbreak. 相似文献
102.
Mohamed Heba I. Mohammed Abdel Haleem M. A. Mohamed Neven M. Ashry Naglaa A. Zaky Laila M. Mogazy Asmaa M. 《Gesunde Pflanzen》2021,73(3):273-285
Gesunde Pflanzen - Cotton leaf worm (Spodoptera littoralis) is considered one of the most destructive agricultural pests in Egypt. It is overcome by the producer by using chemical pesticides, but... 相似文献
103.
Nesrine M. Hegazi Hamada H. Saad Mona M. Marzouk Mohamed F. Abdel Rahman Mahitab H. El Bishbishy Ahmed Zayed Roland Ulber Shahira M. Ezzat 《Marine drugs》2021,19(5)
The Red Sea is one of the most biodiverse aquatic ecosystems. Notably, seagrasses possess a crucial ecological significance. Among them are the two taxa Halophila stipulacea (Forsk.) Aschers., and Thalassia hemprichii (Ehrenb. ex Solms) Asch., which were formally ranked together with the genus Enhalus in three separate families. Nevertheless, they have been recently classified as three subfamilies within Hydrocharitaceae. The interest of this study is to explore their metabolic profiles through ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UPLC-HRMS/MS) analysis in synergism with molecular networking and to assess their chemosystematics relationship. A total of 144 metabolites were annotated, encompassing phenolic acids, flavonoids, terpenoids, and lipids. Furthermore, three new phenolic acids; methoxy benzoic acid-O-sulphate (16), O-caffeoyl-O-hydroxyl dimethoxy benzoyl tartaric acid (26), dimethoxy benzoic acid-O-sulphate (30), a new flavanone glycoside; hexahydroxy-monomethoxy flavanone-O-glucoside (28), and a new steviol glycoside; rebaudioside-O-acetate (96) were tentatively described. Additionally, the evaluation of the antidiabetic potential of both taxa displayed an inherited higher activity of H. stipulaceae in alleviating the oxidative stress and dyslipidemia associated with diabetes. Hence, the current research significantly suggested Halophila, Thalassia, and Enhalus categorization in three different taxonomic ranks based on their intergeneric and interspecific relationship among them and supported the consideration of seagrasses in natural antidiabetic studies. 相似文献
104.
Abdel Nasir M. A. FADEL ELSEED 《Animal Science Journal》2004,75(5):411-415
The effect of ammonia (AS) and urea‐calcium hydroxide (US) treated rice straw as a sole diet on the voluntary intake, digestibility of feed components, nitrogen retention, rumen parameters and microbial nitrogen yield of Suffolk ewes, were compared in a double 2 × 2 latin square design. The digestibility of feed components was not differed in sheep offered either AS or US. Dry matter intake was higher in AS (28 g/kg BW0.75) than US (22 g/kg BW0.75). Although there was high nitrogen intake in sheep given AS diet, this did not result in higher nitrogen retention compared with US diet. No difference was observed in purine derivatives or microbial nitrogen supply between the two groups. The rumen ammonia‐N of sheep offered AS or US exhibited a similar trend in diurnal change with the peak at 1.5–2.5 h after feeding and decline gradually thereafter. However, volatile fatty acid production peaked at approximately 8 h after evening feed and then steadily declined. AS and US diets led sheep to lose weight. In conclusion, urea‐calcium hydroxide treated straw can be used for sheep as an alternative to ammonia treated straw. Without supplementation, ammonia or urea‐calcium hydroxide treated straw was not sufficient even for the maintenance of sheep. 相似文献
105.
Soliman H Abdel Rahman Fatma A Abdel Razek Ashraf M A ‐S Goda Abdel Fattah A Ghobashy Somia M Taha Amal R Khafagy 《Aquaculture Research》2010,41(9):e299-e306
A 63‐day feeding study was conducted to evaluate the effect of partial substitution (0%, 20%, 40% and 60%) of dietary fish meal (FM) with soybean meal (SBM) on the growth performance and feed utilization of speckled shrimp, Metapenaeus monoceros juveniles. A total of 180 M. monoceros juveniles with an average weight of 0.67 ± 0.18 g were equally distributed over 12 glass aquaria (30 L each, triplicate per treatment). All aquaria were filled with filtered sea water (30–35 ‰, salinity). Four isonitrogenous (400 g kg?1 crude protein) and isocaloric (20.5 MJ GE kg?1) test diets were formulated. The control diet contained FM (D1) as the main protein source. In the other diets, FM was partially replaced with 20 (D2), 40% (D3) or 60% (D4) SBM. The results indicate that the diet in which 40% of the FM is replaced by SBM yields similar growth and production, and is as cost effective, as the control diet. 相似文献
106.
Effect of Indian lotus (Nelumbo nucifera Gaertn.) leaf powder on immune status and disease resistance of Nile tilapia 下载免费PDF全文
Afaf N. Abdel Rahman Mohamed ElHady Mohammed E. Hassanin 《Aquaculture Research》2018,49(10):3392-3399
This study assessed the immune response of Nile tilapia (Oreochromis niloticus L.) after feeding on different levels (0.1%, 0.2% and 0.4%) of dietary Indian lotus (Nelumbo nucifera) leaf powder for 45 days. We evaluated both the nonspecific immune response at the end of the feeding period and the resistance to Aeromonas hydrophila. Exposure to Indian lotus resulted in a significant elevation in serum total globulins, serum lysozyme activity, serum killing percentage and the phagocytic activity (p < 0.05). Total serum protein and albumin showed no remarkable variation between tilapia fed on 0.1% Indian lotus and the control group (p > 0.05). In addition, the relative expressions of immune‐related genes, namely interleukin–1β and tumour necrosis factor–α were significantly up‐regulated in tilapia fed on 0.4% Indian lotus as compared to the control group; their expressions were down‐regulated in the other tested groups (p < 0.05). The survival rate of Nile tilapia postchallenge to A. hydrophila reported a significant and dose‐dependent increase in the Indian lotus‐supplemented groups (p < 0.05). Therefore, dietary incorporation of Indian lotus leaves (0.4%, 0.2% and 0.1%) could strengthen the immunity of Nile tilapia and improve its resistance to A. hydrophila infection. Therefore, Indian lotus leaves could serve as potential feed supplements for Nile tilapia. 相似文献
107.
Waleed SENOSY Alaa Eldin ZAIN Abdel‐Razek Khalifa ABDEL‐RAZEK Michiko UCHIZA Nanae TAMEOKA Yoshiaki IZAIKE Takeshi OSAWA 《Animal Science Journal》2012,83(4):284-290
High‐yielding Holstein‐Friesian recipients (n = 43) were used in order to investigate the relation between energy balance status during the early postpartum period and subsequent embryonic mortality after transferring good‐quality frozen embryos. Blood samples were collected during the second, third, fourth, fifth, sixth and seventh weeks postpartum in order to measure energy status indicators. These indicators include β hydroxyl butyric acid (BHBA), non‐esterified fatty acid (NEFA), total cholesterol (T‐chol), glucose and blood urea nitrogen (BUN). Moreover, body condition scores (BCS) were assessed during the same period. Pregnancy diagnosis by ultrasonography at the 28th day postestrus and embryo viability was ascertained until 45 days postestrus in order to detect late embryonic mortality (LEM). The pregnancy rate on day 28 was 44.2% (19/43); however, five cows (11.6%) experienced LEM by day 45. Based on the non‐return rate at day 24, non‐pregnant animals, as diagnosed by ultrasonography, were allocated into animals with longer estrus intervals than 24 days (32.5%; mid‐embryonic mortality (MEM) group) and animals returning to estrus by day 24 postestrus (23.5%; early embryonic mortality (EEM) group). At week 5 postpartum, BCS was significantly (P < 0.05) lower in the LEM group than that of pregnant (PREG), EEM and MEM groups. NEFA was significantly higher in animals that experienced LEM (LEM group) at week 7 postpartum (289.6 ± 47.0 µEq/L; P < 0.01) than that of PREG (196.8 ± 16.0 µEq/L), EEM (157.2 ± 18.6 µEq/L) and MEM groups (191.5 ± 14.4 µEq/L). In conclusion, lower BCS at week 5 postpartum and higher NEFAs at week 7 postpartum may be associated with subsequent LEM in high‐yielding recipient cows. 相似文献
108.
Molecular and morphological identification of the mealybug,Phenacoccus solani Ferris (Hemiptera: Pseudococcidae): first report in Egypt 下载免费PDF全文
During the summer and autumn of 2016, pumpkins, Cucurbita spp. (Cucurbitaceae), were observed to be infested by mealybug species. Populations were collected on various pumpkin fruits from Rosetta, a port city at the North‐Western Nile River delta, Lower Egypt. This study aimed to identify the principle mealybug species infesting the major pumpkin‐producing regions in Egypt, by molecular and morphological characterization. DNA from 15 specimens and morphological data from 22 specimens were used to confirm the identity of the mealybug species. The species present were identified as Phenacoccus solani Ferris, Phenacoccus solenopsis Tinsley, and Planococcus citri (Risso). This is the first record of Phenacoccus solani Ferris (Hemiptera: Pseudococcidae) in Egypt. 相似文献
109.
A nesting colony of hawksbill turtles Eretmochelys imbricata on Seil Ada Kebir Island, in the Suakin Archipelago (Sudan), was studied in March 1978. Sizes of gravid females and their fecundity were compared with other nesting populations. The density of nesting here is higher than that reported at some of the better known hawksbill breeding beaches. Exploitation and conservation of this species in the Red Sea are discussed. 相似文献
110.
The objective of this study was to investigate the dietary effect of vitamin C in amelioration some of studied alterations induced by fenitrothion in Nile tilapia (Oreochromis niloticus). Nile tilapia was exposed to sub-lethal concentration of fenitrothion 0.04 mg/l (96 h LC50 value was 0.8 mg/l), and basal diet was supplemented with two different dose of vitamin C (500 and 1200 mg/kg B wt/day) for 30 days. Vitamin C supplemented groups showed significant decrease in plasma cortisol and glucose level, enzymes activity of liver and gills (catalase, glutathione-S-transferase and superoxide dismutase) and % of tail DNA damage compared to exposed group. Moreover, fish revealed significant increase in total plasma protein, albumin, globulin and A/G ratio. High dose of vitamin C dietary supplementation (1200 mg/kg B wt/day) returns these parameters to its normal levels with no significant difference compared to non exposed control group. These results indicated that incorporation of high dose of vitamin C (1200 mg) in aqua feed for 30 days could be potentially less expensive and effective in reducing the alterations induced by fenitrothion in Nile tilapia. 相似文献