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排序方式: 共有289条查询结果,搜索用时 15 毫秒
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T. Ahmad T. Mushtaq M. A. Khan M. E. Babar M. Yousaf Z. U. Hasan Z. Kamran 《Journal of animal physiology and animal nutrition》2009,93(5):613-621
A 6‐week feeding trial was conducted to determine the effects of varying dietary electrolyte balance (DEB) on growth performance and physiological responses in broiler chicks reared during hot summer months (26.1–37.5 °C). The average minimum and maximum room temperatures recorded from 14 to 42 days of age were 26.1 and 37.5 °C, respectively, with relative humidity ranging from 51% to 55%. Five DEB treatments supplying 0, 50, 150, 250 and 350 (Na++K+–Cl?) mEq/kg of diet were prepared by adding NaHCO3 and/or NH4Cl to basal diet that contained 185 mEq/kg from 1 to 28 days and 172 mEq/kg from 29 to 42 days. These DEB diets were randomly offered to six experimental units of 20 chicks each. Improved 42‐day body weight gain (BWG), feed:gain (F:G) and reduced mortality was noted with DEB 50, 150 and 250 mEq/kg compared to DEB 0 and 350 mEq/kg. A quadratic effect of increasing DEB level was observed on BWG and F:G, whereas the effect was linear for feed intake, water intake and litter moisture. The DEB 50, 150 and 250 maintained better blood pH, pCO2 and HCO3 concentrations during acute heat stress periods than that of 0 and 350. The blood heterophil and lymphocyte percent as well as heterophil:lymphocyte were remained unaffected. The lowest DEB (0 mEq/kg) diet reduced the feed intake and promoted metabolic acidosis. At 350 mEq/kg DEB, water intake and metabolic alkalosis were promoted probably due to high levels of dietary NaHCO3. The study concluded that overall better performance was recorded with DEB 50, 150 and 250 mEq/kg. These results indicated that single optimal DEB value could not be recommended to combat heat stress in broilers. 相似文献
3.
Kubra Karakas Alkan Ahmet Ceylan Hasan Alkan Dogukan Ozen Alev Gurol Bayraktaroglu Mustafa Kaymaz 《Reproduction in domestic animals》2019,54(7):979-986
The aim of this study was to determine the serum concentrations, ovarian presence and expression of anti‐Müllerian hormone (AMH) in pre‐pubertal, bitches with signs of ovarian remnant syndrome (ORS) and intact bitches. In addition, we aimed to verify the suitability of serum AMH concentrations for diagnostic purposes in sterilized bitches and/or in suspected cases of ORS in the field of veterinary medicine. For this purpose, 36 healthy female dogs divided into six groups: proestrus, oestrus, dioestrus, anoestrus, pre‐pubertal and ORS. Serum AMH concentrations were determined by electrochemiluminescence immunoassay, and ovarian presence and distribution of AMH was confirmed by immunohistochemical and qPCR techniques. According to the results of qPCR, while the expression values of AMH were at the highest concentrations in the proestrus and oestrus, there was a statistically significant decrease in these values at the later stages of the cycle (p < 0.05). According to hormone analysis, the serum AMH values of the ORS group had decreased significantly compared with the proestrus and oestrus (p < 0.05). Although serum AMH levels of ORS group were increased compared with anestrus and pre‐pubertal groups, this increase was statistically non‐significant (p > 0.05). Immunohistochemically, AMH expression was first observed in the granulosa cells of primordial follicles in folliculogenesis. Expression values were the highest in the proestrous and oestrus groups, but values from bitches in later stages of the cycle were statistically significant decrease in comparison with these groups (p < 0.05). As a result, AMH concentration and expression were found to be higher in proestrus and oestrus than in other periods (p < 0.05). In addition, the measurable level of AMH concentration in bitches with ORS is an indication that it can be used in the diagnosis of ORS. 相似文献
4.
Hasan Meydan Mehmet A Yildiz Fulya ?zdil Yasemin Gedik Ceyhan ?zbeyaz 《Acta veterinaria Scandinavica》2009,51(1):5
Background
Factor XI (FXI) is a plasma protein that participates in the formation of blood clots. Factor XI deficiency is autosomal recessive hereditary disorder that may be associated with excess bleeding in Holstein cattle.Methods
In this study, 225 Holstein cows reared in Turkey were screened in order to identify FXI genotypes. DNA extractions were obtained from the fresh blood of the cows. Amplicons of FXI exon 12 were obtained by Polymerase Chain Reaction (PCR), and analyzed by 2% agarose gel electrophoresis stained with ethidium bromide. Additionally, all cows were confirmed by DNA sequencing to determine whether or not there was a mutant allele.Results
Carriers of the FXI deficiency have two DNA fragments of 320 bp and 244 bp in size. The results of our study demonstrated that only four out of the 225 Holstein cows tested in Turkey carried the FXI deficiency. The frequency of the mutant FXI allele and the prevalence of heterozygous cows were found as 0.9% and 1.8%, respectively.Conclusion
The DNA-based test determines all genotypes, regardless of phenotype or FXI activity. The mutation responsible for the FXI deficiency had not been detected in Holstein cattle in Turkey before prior to this study. The frequency of the mutant FXI allele needs to be confirmed by carrying out further analyses on cattle in Turkey and the selection programs should be developed to eliminate this genetic disorder. 相似文献5.
Cihan Ka?ar Kadir ?zcan ?smet Tak?? Kutlay Gürbulak Hasan ?zen Musa Karaman 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(4):429-431
Congenital malformations with multiple anomalies have been described infrequently in the veterinary literature. A stillborn male crossbred lamb with diprosopus, craniorachischisis, and arthrogryposis was examined macroscopically and histopathologically in this study. The left head was smaller than the right head. Micrencephaly, agnathia, and a rudimentary tongue, which was adherent to the palate, were present in the left head. Micrencephaly, brachygnathia superior, and cleft palate were present in the right head. Cerebellar agenesis and spinal cord hypoplasia were observed. The cerebrums and the spinal cord were covered with a tapering membranous structure. Neural and dermal tissues were noted to intervene upon microscopic examination of this structure. Disorganization of neurons was observed in both cerebrums, though it was more severe in the left one. This case demonstrates many congenital defects occurring together in a lamb. 相似文献
6.
Yousefi Babak Gholizadeh Mohsen Hafezian Hasan 《Tropical animal health and production》2020,52(6):3217-3223
Tropical Animal Health and Production - The aims of this study was to evaluate inbreeding effects for growth rate (average daily gain from hatch to 8 weeks of age (ADG1–8), average... 相似文献
7.
Badrul Hasan Kamrul Islam Murshidul Ahsan Zakir Hossain Mahmudur Rashid Bibhas Talukder Kabir Uddin Ahmed Björn Olsen Mohammad Abul Kashem 《Veterinary microbiology》2014
Antibiotic resistance and ESBL constitute a risk to human and animal health. Birds residing close to humans could mirror the spectrum of human associated antibiotic resistance. Household pigeons were screened in Bangladesh to shed light on human associated, as well as, environmental antibiotic resistance. Escherichia coli from pigeons (n = 150) were tested against 11 antibiotics. 89% E. coli isolates were resistant to one or more critically important human antibiotics like ampicillin, cefadroxil, mecillinam, ciprofloxacin, gentamicin and tigecycline. No carbapenamase-producers were detected and the lower ESBL prevalence (5%) in pigeons. ESBL-producing E. coli isolates had blaCTX-M-15 genes. Pigeons shared some bacterial clones and had bird associated sequence types like E. coli ST1408. Fecal carriage of bacteria resistance of critically important human antibiotics, together with examples of shared genotypes among pigeons, indicate the human-birds and bird to bird transmissions are important in the epidemiology of antibiotic resistance. 相似文献
8.
Gyula Vida Mariann Gál Andrea Uhrin Ottó Veisz Naeem Hasan Syed Andrew J. Flavell Zhulin Wang Zoltán Bedő 《Euphytica》2009,170(1-2):67-76
The resistance genes Lr9, Lr24, Lr25, Lr29, Lr35 and Lr37, which were not previously utilised in Hungary, have been incorporated into four Martonvásár winter wheat cultivars using marker-assisted selection with PCR-based markers. In the course of a backcross programme, the genes were transferred into Martonvásár wheat varieties and various BC generations were produced. Work aimed at pyramiding resistance genes is currently underway in Martonvásár, and plants containing the gene combinations Lr9 + Lr24, Lr9 + Lr25 and Lr9 + Lr29 are now available. From the BC2F4 generation of the ‘Mv Emma’*3/’R.L.6010’ combination (‘R.L.6010’ is the donor of the Lr9 gene) 287 lines were tested for leaf rust resistance in an artificially inoculated nursery. A co-dominant primer combination was designed to identify both resistant and susceptible offsprings. The results of resistance tests and molecular marker detection agreed in most cases. Designated leaf rust resistance genes were identified with molecular markers in wheat varieties and breeding lines. The Lr26 and Lr34 resistance genes occur frequently in the Martonvásár gene pool, and the presence of the Lr37 gene has also been detected in a number of Hungarian genotypes. 相似文献
9.
The state of urban seedling nurseries in the north-eastern region of Bangladesh is examined with a focus on production and profitability of the enterprises. Twenty-eight sample nurseries out of the 97 nursery enterprises in Sylhet town were selected at random, and operators personally interviewed. It was found that the entrepreneurs are not highly educated though they believed that a basic level of education is required to understand the management of young nursery stock. Labourers of various employment categories work in the enterprises and their wage is determined by their skill, gender and efficiency. Capital and operating costs vary among the enterprises according to land value, production capacity, infrastructure type and workforce size. Production capacity ranges from 10,000 to 5 M seedlings/year with an average 836,000, though actual average production is only 341,000 seedlings/year. The production cost per seedling ranges from Tk. 4 to 50 while sale value ranges from Tk. 10 to 60. The most frequently sold species are Acacia mangium, Swietenia macrophylla, Tectona grandis, Mangifera indica, Litchi chinensis and Cocos nucifera. Nursery techniques and cultural practices adopted by nursery operators depend on the type of species and its silvicultural requirement. Despite some problems, including lack of suitable land for nursery establishment and inadequate level of technical knowledge for high quality seedling management, it seems that production of tree seedlings is a promising profitable small-scale business in the study area. 相似文献
10.
Antibacterial activity of Barringtonia racemosa 总被引:3,自引:0,他引:3
The antibacterial activity of the ethanol extract of Barringtonia racemosa roots, its chloroform soluble fraction and, a there from an isolated clerodane diterpenoid is reported. 相似文献