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921.
922.
One hundred and eight isolates of Phytophthora infestans were collected from infected potato and tomato crops in the middle-north of Morocco during 1997–2000. Pairings of these isolates with tester isolates of mating type A1 and A2 revealed that 60% of the isolates were mating type A2 (65/108) and 40% were mating type A1. After 10 days incubation at 20 °C and a 16-h photoperiod, approximately 25% and 18% of the oospores produced in-vitro germinated in potato soil extract and potato root extract, respectively. Oospores were observed in potato leaf tissues in pairings that were fertile in-vitro. Maximum production of oospores was obtained in potato leaves of cultivars that were moderately susceptible (Desirée, Nicola) after 10 days of incubation at 15 °C and a 16-h photoperiod. These results confirm the presence of P. infestans strains that are sexually compatible under Moroccan climatic conditions. Production of oospores constitutes a threat for these crops because of the occurrence of recombinants with new virulences which may be difficult to control and as a consequence survival of oospores in absence of the host plant in the soil.  相似文献   
923.
Myostatin is a potent growth and differentiation factor involved in skeletal muscle tissue formation in vertebrates. However, recent studies in chicken embryo suggested that the myostatin was expressed even before the establishment of myogenic lineage. No studies have thus far been reported in birds to define the role of myostatin during the embryonic organogenesis. The present experiment was designed for studying the expression profiles of myostatin mRNA in the chicken liver, heart, brain, and intestine during their morphogenesis, using real-time PCR. The myostatin mRNA expression was significantly upregulated in liver during E15-E18. Similar results were observed during the development of chicken heart. In brain, the expression of myostatin was upregulated from E4 onwards. In intestine, the expression of myostatin was significantly increased many folds on E9-E18. Therefore, the increase in myostatin expression might be related to the growth of liver and heart on days E12-E18; morphogenesis and growth of brain during E15-E18; and morphogenesis and differentiation of intestine during E9-E18. In the present study, the tissue-specific expression of myostatin gene in chicken is similar to fishes, but different from that in mammals. Further, the inspection of chicken genome also suggested that there is no differentiation of GDF-8 and -11. A recent finding suggests that the chicken myostatin gene is closely related to mammals than fishes. Therefore, we propose that the chicken myostatin gene might have diverged in its function between teleosts and mammals. Indeed it is possible that its function might have only become fully differentiated to serve as a control of muscle mass in mammals.  相似文献   
924.
925.
1. Toxic effects of two concentrations (0.5 and 1 mg/kg) of ochratoxin A (OTA) and attenuating effects of a toxin deactivator (Mycofix Plus(MTV INSIDE)) containing the yeast Trichosporon mycotoxinivorans on the performance (feed conversion ratio; body weight gain), serum enzymes (lactate dehydrogenase, gamma-glutamyltranspeptidase and aspartate aminotransferase) and clinico-pathomorphology of internal organs were studied in 270 one-day-old broiler chicks divided into 9 groups over a 42-d period. 2. Feed conversion ratios (FCR) in groups fed toxin deactivator were improved compared with groups receiving OTA only. An increase in the relative weight of kidney and liver was observed in groups fed 0.5 and 1 mg/kg OTA on day 42 of the experiment as compared with the control group. In contrast, relative weights of bursa of Fabricius and spleen were not significantly affected in experimental groups exposed to OTA as compared to control groups determined on days 28 and 42 of age. 3. Serum enzymes (LDH, GGT and AST) values in OTA treated groups determined on days 28 and 42 were higher than those of the control group. 4. Histopathological examination of kidney on day 42 revealed degenerative changes in the epithelial cells of the proximal convoluted tubules and massive necrosis of the proximal tubular epithelial cells. These changes were less marked in birds receiving 0.5 mg/kg OTA than in those receiving 1 mg/kg. In general, histological changes in kidneys, liver, bursa and spleen were less pronounced in birds receiving OTA and toxin deactivator concomitantly. 5. Dietary OTA at 0.5 and 1 mg/kg adversely affects FCR, increases the serum liver enzymes and induces pronounced pathomorphological and histological changes in internal organs of broiler chicks. Co-administration of OTA with deactivator attenuated the harmful effects.  相似文献   
926.

Dermatophytosis is a contagious fungal disease among animal communities. The major concerns of dermatophytosis are cost of treatment, difficulty of control, and the public health consequences. The objective of the present study was to compare the clinical efficacy of Sumaq and Neem extract cream with that of traditional treatments, eniloconazole and glycerine iodine, on dermatophytosis in Arabian horses. For this purpose, 37 Arabian horses with dermatophytosis had been used. Fungal isolation and identification for each horse were carried out by standard microbiological procedures. Sumaq (Rhus coriaria Linn.) and Neem (Azadirachta indica) seed extracts were selected based on in vitro effectiveness. Horses were randomly allocated into four groups. The first group (n?=?8) was treated with glycerine iodine 10% daily for 7 days. The second group (n?=?10) was treated using eniloconazole 10% emulsified concentrate four times with 2 days interval. The third group (n?=?11) was treated with Neem seeds extract (20% cream) daily for 10 days, and the fourth group (n?=?8) was treated with Sumaq extract (5% cream) daily for 10 days. Clinical and mycological evaluations were assessed at 0, 7, 14, 21, and 28 days post-treatment. The Sumaq and eniloconazole were more effective on clinical index score after 7 days of treatment followed by Neem seed 20% cream. At 28 days post-treatment, a complete healing was obtained by Sumaq 5% cream and eniloconazole (median clinical sum score?=?zero) followed by Neem (median clinical sum score?=?1.5). Moreover, Dermatophytes spp. was isolated only from two horses, one from Neem group and the other from glycerin iodine group. The present results indicate that Sumaq 5% and Neem seed extract are effective alternative treatment for dermatophytosis in Arabian horses.

  相似文献   
927.
This study was conducted to evaluate the effect of Zingiber officinale and Thymus vulgaris aqueous extracts as a natural antioxidant on liver and kidney functions and antioxidant status of growing rabbits. A total of 24 V‐line male rabbits, 3 months old, 1.465 ± 0.12 kg average body weight (BW) were used in a complete randomized design. The rabbits were weighed individually and assigned randomly to four groups (6 animals/each). The first group (G1) was taken fresh water and served as control, rabbits of the second group (G2) were taken 100 mg/kg BW in drinking water of the Z. officinale aqueous extract daily. The third group (G3) was taken 50 mg/kg BW in drinking water of the T. vulgaris aqueous extract daily and the fourth group (G4) was taken 100 mg/kg BW of the Z. officinale aqueous extract plus 50 mg/kg BW of the T. vulgaris aqueous extract in drinking water daily. The oral administration of ginger and/or thyme aqueous extracts increased (p < .001) serum protein profile compared with control group. Moreover, results of group 2 showed significant (p < .001) decrease in cholesterol, triglyceride and very low‐density lipoprotein cholesterol compared with group 3 and 4. Serum urea, uric acid and creatinine levels were significantly (p < .001) decreased in treated groups compared with control group. Oral administration of ginger and/or thyme aqueous extracts to growing rabbits increased (p < .001) total antioxidant capacity and glutathione content and the activity of superoxide dismutase, catalase and glutathione‐S‐transferase compared with the control group. In conclusion, the current study showed that oral administration of ginger and thyme aqueous extracts to growing rabbits showed no adverse effects on liver and kidney function parameters, histological structures and improved antioxidant status.  相似文献   
928.
This study aimed to investigate the potential toxic effects of pure glyphosate or Roundup® on hatchability, serum biochemistry and histopathological observation of the liver and kidney of newly hatched chicks. On day six, a total of 225 fertile eggs were obtained from Huafeng breeder hens. The eggs were randomly divided into three treatments: (a) the control group injected with deionized water, (b) the glyphosate group injected 10 mg pure glyphosate/Kg egg mass and (c) the Roundup group injected 10 mg the active ingredient glyphosate in Roundup®/Kg egg. The results showed a decrease of hatchability rate in chicks treated with Roundup® (66%). In addition, no significant change was observed in body weights, yolk sac weight and relative weight organs except the liver and kidney were significantly increased with groups treated with glyphosate and Roundup® compared to the control group. The results showed that serum protein profiles were linearly significantly increased of serum phosphor, uric acid, aspirate aminotransferase, alanine transaminase and alkaline phosphatase in groups treated with Roundup®, as well as the serum concentrations of triglyceride altered after treatment with glyphosate. Furthermore, oxidative stress was observed in the treated chicks, the glyphosate and Roundup® induced changes of the content of malondialdehyde in both the liver and kidney, moreover decrease of glutathione peroxidase, total superoxide dismutase and catalase activity in the kidney tissue and serum. Additionally, changes also happened in the histomorphology of the liver and kidney tissue of the treated chicks. It can be concluded that Roundup® as a probable decrease of hatchability. Exposure to glyphosate alone or Roundup® caused liver and kidney histopathological alterations, serum parameters imbalances and oxidative stress, also induced a variety of liver and kidney biochemical alterations that might impair normal organ functioning in newly hatched chicks.  相似文献   
929.
The aim of this study was to explore the genetic polymorphisms in LTF/EcoRI and TLR4/AluI loci and their association with milk and reproductive performance in Holstein cattle. A randomly selected 800 Holstein dairy cows from two dairy farms (400 animals each) in Egypt were used. Based on the two farm records, association between LTF/EcoRI genotypes and milk performance traits (order of lactation, daily milk yield, days in milk, corrected milk at 305 day and dry period) was carried out. Meanwhile, exploring of TLR4/AluI genotypes effect was done on data for reproductive performance (age at first freshening, calving interval, number of services per conception, ovarian rebound and days open). DNA was extracted from blood samples collected from Holstein dairy cows of the both farms and restriction analysis of 301‐bp PCR products of LTF gene revealed two genotypes: AA genotype (301 bp) and AB genotype (301, 201 and 100 bp). Meanwhile, restriction analysis of 382‐bp PCR products of TLR4 gene digested with AluI yielded two alleles (A and B) and three genotypes (AA, AB and BB). The A allele was indicated by two bands at 300 and 82 bp, and the B allele resulted in three fragments of 160, 140 and 82 bp. There was a significant association (p ≤ 0.05) between LTF genotypes and milk performance traits except for days in milk. The TLR4 genotypes had significant effects (p ≤ 0.05) on age at first freshening, calving interval, number of services per conception, ovarian rebound and days open. Ordinal logistic regression statistical model also revealed that it is possible to calculate high reproductive performance traits and to predict favourable dairy cows based on LTF and TLR4 genotypes. This research reveals the effectiveness of LTF/EcoRI and TLR4/AluI loci as candidates for reproductive performance assessment in Holstein cattle.  相似文献   
930.
This study examined the mitogenic response of bovine peripheral T lymphocytes to leptin, a pleiotropic hormone regulating food intake and energy expenditure. Leptin alone slightly suppressed proliferation of T lymphocytes in the presence of concanavalin A (ConA). Leptin also inhibited proliferation of T lymphocytes induced by anti-CD3 antibody. ConA treatment activated some protein kinases, including p44/p42(MAPK) and Akt/PKB, while anti-CD3 antibody treatment increased mRNA expression of suppressor of cytokine signalling (SOCS) 3, interferon (IFN)gamma, interleukin (IL) 2 and IL4 in T lymphocytes. Leptin alone increased only SOCS3 mRNA expression. Simultaneous treatment with mitogens and leptin enhanced IFNgamma mRNA expression but decreased IL2 mRNA expression, without any synergistic effect on phosphorylation of protein kinases or mRNA expression of SOCS3 and IL4. These results suggest that leptin modulates bovine T lymphocyte functions.  相似文献   
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