خيارات البحث
النتائج 51 - 60 من 465
Changes in buffalo serum and hepatic lipid parameters in response to food restriction
2015
Shekarian, Mirhamed | Nouri, Mohammad | Haji Hajikolaei, Mohammad Rahim | Shahriari, Ali | Mohammadian, Babak | Pourmahdi Borujeni, Mehdi | Ghadiri, Ali
BACKGROUND: Negative energy balance in cow occurs in transitional period, high-yielding dairy cows immediately after calving and feed restriction. In response to energy demand cow mobilizes fatty acids from adipose tissue causing an increase in the circulation of NEFA. Increased blood NEFA is associated with low glucose, high free fatty acids and ketone bodies as well as lipid and lipoprotein disturbances in the blood. Does buffalo follows the same as cow, is not yet cleared. Objectives: The purpose of the present study was to investigate the effects of starvation on some lipid parameters in serum and liver of buffalos in Ahwaz. Methods: Five two-year-old male buffalos with average body weight of 200 kg were fattened with a diet containing alpha, barely, wheat, and maze for 8 weeks and then they were fastened for 8 days. During fasting period the animals had free access to barely and water. After fasting period the buffalos were again fattened for 8 weeks. Blood samples were collected from the coccygeal vein during the first and second fattening period with 20 days intervals and every day in the fasting period. Plasma samples were obtained, stored, and analyzed for glucose, BHBA and NEFA using standard kits. The liver of each buffalo was sampled at the beginning and end of feed restriction period and sent to the laboratory for the measurement of the liver TG content. Analyses of variance were carried out to compare mean values in fed and fasted periods. Results: The results of present study revealed that there were no significant differences in plasma NEFA ,BHBA and liver TG concentration before and after feed restriction (p>0.05), but there was significant difference in plasma glucose (p|£|0.05). Conclusions: It appears that in the period of food depravation, buffalos are essentially able to cope with these hard conditions probably through control of lipolysis and gluconeogenesis at the aim of preventing metabolic disorders particularly fatty liver. The results of the present research reveal probably for the first time, this inheritance phenomenon with the emphasis of further research.
اظهر المزيد [+] اقل [-]Allelic segregation of major histocompatibility complex using LEI0258 microsatellite marker in indigenous and commercial chickens
2015
Esmailnejad, Atefeh | Nikbakhat, Gholamraza | Khazeni Oskoui, Neda | Amini, Farhad
BACKGROUND: Major histocompatibility complex (MHC) in chicken has profound influence on resistance/susceptibility to disease, and production and reproduction traits. Microsatellite marker LEI0258 is a genetic indicator for MHC haplotypes. Recognizing diversity of MHC haplotypes in selectively bred populations will be helpful for selecting population resistant to disease and development of effective vaccines. Objectives: The purpose of the present study was to evaluate polymorphism at MHC in two populations of Khorasan indigenous chickens and commercial Leghorn breed using microsatellite marker LEI0258 and to investigate its segregation and heredity. Methods: A total of 335 blood samples from Khorasan Razavi indigenous chickens and commercial Leghorn population including parents (P) and offspring (F1), were analyzed. The MHC genotypes were determined using LEI0258 microsatellite. The study of allele heredity from P to F1 and Hardy-Weinberg equilibrium were conducted using Chi-square and Likelihood Ratio tests. Results: In Khorasan indigenous chickens 20 different alleles were identified for LEI0258 microsatellite. The allele 321 bp had the highest (22.88%) and the allele 182 bp had the lowest (0.16%) frequency. In the commercial population (Leghorn breed) 3 alleles were found for this marker of which the allele 261 bp had the highest (50%) and alleles 487 bp had the lowest (6 %) frequency. In allele heredity analysis and Hardy-Weinberg equilibrium of Khorasan population, no significant differences were observed between P and F1 progenies. ConclusionS: These results indicate a higher genetic variation in indigenous chickens compared to commercial breed. There was no preference for a particular allele in indigenous chickens. The higher frequency of some alleles in F1 population is due to the high frequency of the same alleles in parent population which their gametes make the population gene pool.
اظهر المزيد [+] اقل [-]Optimum dose of gamma irradiation to inactivate Vibrio paraheamolyticus in fresh and freeze-dried
2015
Heidarieh, Marziye | Soltani, Mahdi | Motamedi sedeh, Farahnaz | Rajabifar, Saeed | Ahmadi, Mohammad Reza | Shahhoseini, Gholamreza
BACKGROUND: Vibrio paraheamoloyticus is one the causative agents of vibriosis with high mortality in farmed fish and shrimp and under predisposing conditions. OBJECTIVES: This study was aimed to assess the effect of gamma irradiation on the inactivation of V. paraheamoloyticus under fresh and freeze-dried conditions. METHODS: Vials of 0.5 ml fresh culture of the bacterial suspensions at 1.5*1010 cfu/ml were subjected to 1, 1.5,2, 2.5, 3 and 4 KGy. Also, vials of 0.5 ml freeze-dried culture of the bacterial suspensions at 1.5 x 1010 cfu/ml were subjected to 2, 4, 7 and 8 KGy. The bacterial growth behavior was then evaluated on fresh medium. RESULTS: The obtained results showed that the minimum doses of 4 and 10 KGy were sufficient for the inactivation of fresh and freeze-dried bacteria, respectively. CONCLUSIONS: The result of this study shows that inactivation of V. paraheamolyicus in fresh culture condition requires below half- dosage of gamma ray required for the inactivation of the freeze- dried of bacterial cells.
اظهر المزيد [+] اقل [-]Thyroid hormones changes in reproduction season of brownbanded bamboo shark (Chiloscyllium punctatum) from the Persian Gulf
2015
Alimi, Rahman | Savari, Ahmad | Movahedinia, Abdolali | Zakeri, Mohammad | Salamat, Negin
BACKGROUND: Brownbanded Bamboo sharks (Chiloscyllium punctatum) is one of the cartilaginous fish that lives in the Persian Gulf. OBJECTVES: The purpose of the present study is to study the effects of thyroid hormone on reproductive system of this specious. METHODS: In this investigation, 36 individual of Brownbanded Bamboo sharks (Chiloscyllium punctatum) in both autumn (before reproduction) and spring (period of reproduction) seasons were caught from Dervish’s Creek located at the northern of Persian Gulf. After weighing, biometry, sex determination and the numbering of sharks, (the sex is determined through clasper which is observed in male and not in female), ELISA was used to measure serum thyroid hormone concentrations. RESULTS: The results showed that T3 and T4 hormones were increased dramatically in the reproductive season compared with the non-breeding season (p<0.05). On the other hand, by classifying the sharks into different groups, we found that the levels of thyroid hormone were higher in the blood of larger sharks compared with the smaller ones (p<0.05). CONCLUSIONS: It is probable that T4 hormone levels will increase dramatically for the development of eggs in the female shark.
اظهر المزيد [+] اقل [-]Histomorphological study on silver carp ovary in two age groups
2015
Erfani Majd, Naeem | Mesbah, Mehrzad | Rahimi Zarneh, Sara
BACKGROUND: Maturity of silver carp (Hypophthalmichthys molitrix) ovary takes place at 2-8 years old and it is depends on photoperiod and environmental water temperature. Objectives: The aim of this study was to identify macroscopical and microscopical structure of silver carp ovary in two categories of body weight, total body length and at 2 and 4 years old in Khuzestan province climatic conditions. Methods: 20 silver carp ovaries were studied in two groups: Group 1(G1): 10 fish with total body length 46 ±1.33 Cm and weight 1050±0.09 grand approximately 2 years old. Group 2(G1): 10 fish with total body length 86±3.64 Cm and weight 5460±800 gr and approximately 4 years old. For the histometrical studies, 5-6 µ sections were made by routine paraffin embedding method and stained by H&E and PAS. Results: Microscopic results showed that ovaries of G1 covered by a thin loose connective capsule which numerous of egg-bearingtrabecula extended from capsule into ovaries. These trabecula contained primary germ cells, oogonium, chromatin nocleolus, perinocleolus and cortical alveolus follicles. Ovaries of G1 do not have yolk and mature follicles. But in ovaries of G2, growth and mature follicles were observed and mature follicles were most follicles. Histometrical results showed that there are not a significant differences in diameter of follicles, oocytes and oocytes nucleolus in G1 and 2. The maximum and minimum diameter of follicles were seen in mature and chromatin nucleolus follicles respectively. The Zona plucida thickness was increased from corticalalveolus (1.53±1.11 mm) to mature follicles (6.88±0.21 mm) significantly (p<0.05). ConclusionS: The most interesting finding of this study is that in Khuzestan Province climate, the ovary of silver carp fish in G1, with average weight 1050 ±0.09 gr and total length 46±1.33 Cm and approximately of 2 years old is immature but ovary of G2 with average weight of 5460± 800 gr and total length 86±3.64 Cm and approximately 4 years old is mature.
اظهر المزيد [+] اقل [-]Effect of controlled heating of colostrum on immunoglobulins absorption, performance and certain health parameters in calf
2015
Vakili-Saleh, Fahimeh | Moslemipur, Farid | Mostafaloo, Yousof
BACKGROUND: The immunity and health of newborn calf are related to immunoglobulins uptake from colostrum where treatment of colostrum may improve the uptake. Objectives: The purpose of this study was to investigate the effect of controlled heat-treating of colostrum and antibiotic addition on immunoglobulins absorption, performance and health parameters of calf. Methods: The colostrum pool was prepared from multiparous dams and was frozen after the treatments. Colostrum was fed immediately after the birth three times a day for 2 days. Twelve newborn Holstein calves were divided into three treatment groups including 1) raw colostrum (control), 2) heat-treated colostrum, and 3) colostrum with oxytetracyclin in a completely randomized design. Blood samples were obtained in days 0, 7, 14, 21 and 28 via jugular vein. Health score and fecal point were determined daily. Results: Results showed that heat-treating of colostrum increased immunoglobulins uptake and their apparent efficiency of absorption (p<0.01), where a 24% increase in blood immunoglobulins concentrations and a 15% in their apparent efficiency of absorption were observed by heating the colostrum compared with control group and a lower increase was observed compared with antibiotic group. No significant differences were observed in weight gain, weaning time and weight as well as the amount and time of beginning starter intake among groups. Feed conversion ratio did not affected by the treatments. There were no significant differences in blood cells counts among groups. Calves fecal point was not affected by the treatments but health score was increased by using heat-treated colostrum where scour incidence was reduced (p<0.05). Conclusions: Results of the study showed that controlled heat-treating of colostrum is an effective and practical method to improve immunoglobulins absorption and reduce scour incidence in calf.
اظهر المزيد [+] اقل [-]The effect of different levels of L-carnitine on performance, blood parameters and carcass characteristics of broiler chickens fed with high fat diets under heat stress condition
2015
Babazadeh Aghdam, Ahmad | Ghazi Harsini, Shahab | Daneshyar, Mohsen
BACKGROUND: Heat stress declines the performance through physiologic changes of the poultry. OBJECTIVES: This experiment was conducted to evaluate the effects of different levels of L-carnitine on performance, carcass characteristics and some blood parameters of broiler chickens fed with high fat diets under heat stress. METHODS: Two hundred one-day-old broiler chicks (Ross 308) were used in a completely randomized design by four treatments and five replicates (pen) 10 birds in each replicate. The chickens of experimental treatments were fed with basal diet (control group) and the diets plus the different levels of 100, 200 and 300 mg/kg L-carnitine. The experimental diets were used during the finisher period (day 24 to 42 of age) and under heat stress (32±1ºC as cyclic from 9.00 AM to 5.00 PM). RESULTS: The results showed that the chicks fed with the highest L-carnitine had the higher weight gain during the finisher period as compared to control and the lower L-carnitine fed chicks (p<0.05). Furthermore, the feed conversion ratio of birds fed with the medium and high L-carnitine levels (100 and 300 mg) was lower than that of control birds (p<0.05). In orthogonal contrasts, L-carnitine supplementation caused the improvement in weight gain and feed conversion ratio during both the finisher and whole experimental periods (p<0.05). The consumption of highest L-carnitine decreased the abdominal fat as compared to control (p<0.05). In orthogonal contrasts, L-carnitine consumption caused the higher glucose and lower abdominal fat in comparison to control (p<0.05). CONLUSIONS: Totally, the results of recent experiment show that consumption of 300 mg/kg L-carnitine improves the performance of broiler chickens through the increase in dietary fatty acids and energy.
اظهر المزيد [+] اقل [-]An evaluation of alfalfa for molt induction on intestinal morphometric parameters and performance of commercial laying hens
2015
Shahrami, Ehsan | Rezaian, Maryam
BACKGROUND: The use of feed withdrawal for molt induction can negatively affected the structure and microbial environment of intestine and lead to greater intestinal colonization by salmonella infection. OBJECTIVES: The aim of the present experiment was to determine the effects of alfalfa as a high fiber ingredient for molt induction on intestinal morphometric characteristics and performance of commercial laying hens. METHODS: In this experiment 108 Hy-line (W36) laying hens aged 74 weeks in a completely randomized design with 3 treatments and 6 replicates were used. Using treatments for 12 days molt period were included: 1- control group fed with layer ration (FF), 2- feed withdrawal group (FW), 3- group fed with 90% alfalfa and 10% layer ration (A90). Performance of birds was monitored for 12 weeks after the end of the molting period. RESULTS: Feed withdrawal hens had lowest villus height in all three regions of the intestine (p<0.05).The highest average of deudenal crypt depths was observed in FW hens. In all three regions of the intestine, the lowest amounts of villus index and villus surface was observed in FW hens (p<0.05). In all three regions of the intestine, the highest and lowest average of goblet cells was seen in the A90 and FW hens respectively. The highest mean of post molt egg mass was observed in FW hens (p<0.05). The best FCR was seen in the A90 group. CONCLUSIONS: The use of alfalfa-riched feed for molt induction of laying hens results in improvement of morphometric characteristic of intestine and post molt performance.
اظهر المزيد [+] اقل [-]Surveillance study of faecal E. coli isolates producing AmpC and extended spectrum β-lactamases (ESBLs) enzymes in poultry and workers from aviculture around Tehran
2015
Doregiraee, Fatemeh | Nayeri Fasaei, Bahar | Alebouyeh, Masoud
BACKGROUND: AmpC and ESBLs as mediated-plasmid extended spectrum β-lactabases are the main factors of resistance to extended-spectrum cephalosporins in enterobacteriacea especially E. coli and will follow treatment failure, high costs of treatment in human and economic losses in the poultry industry. OBJECTIVES: The purpose of this study was to screen and study the faecal E. coli isolates producing extended spectrum β-lactamases (ESBLs) and AmpC enzymes and related workers. METHODS: A total of 500 cloacal swab samples from broiler chickens and 25 rectal swab samples from workers were collected from five poultry houses around Tehran. All samples were seeded on MacConkey agar and identification of E. coli isolates were performed via biochemical tests. Antibiotic susceptibility was determined against 12 antibiotics using the disk diffusion method as recommended by the clinical and laboratory standard institute (CLSI2012). Ceftazidim / ceftazidim-clavolanic acid and cefoxitin / cefoxitin-EDTA disks were used for the detection of ESBL and AmpC phenotypes, respectively. phonetic analysis of the drug resistances was performed via SPSS software and Chi-square test. ESBL- producing E. coli screened by PCR for the presence of genes encoding beta-lactamases of TEM, CTX-M and SHV. RESULTS: A total 467 E. coli isolates were isolated from 88.9% of the samples as 92% and 72.7% of isolates presenting MDR phenotype among chickens and workers respectively. ESBL phenotype detected in 5.5% (26) of poultry isolates while, none of the workers isolates have this phenotype. Six isolates carried both of TEM and CTX-M whereas, five and one isolates were detected only for TEM and CTX-M, respectively. Eighty-eight and nine-tenths percent of ESBL E. coli displayed AmpC phenotype. CONCLUSIONS: Since cephalosporins are not used in broilers in Iran, isolation of faecal E. coli isolates producing extended spectrum β-lactamases in broilerchickens can indicate transfer of the resistance genes via plasmids and other mobile genetic elements among Enterobacteriaceae.
اظهر المزيد [+] اقل [-]Changes in gene expression of metabolically active proteins in ruminal epithelium of lambs fed with oil and monensin
2015
Mirzaei-Alamouti, Hamid Reza | Moradi, Saeede | Razzazian, Arman | Harkinezhad, Mohammad Taher
BACKGROUND: High grain diets in ruminants increases the risk of digestives disorders such as acidosis which may lead to high economic loss. OBJECTIVES: This experiment was conducted to determine the effects of an unsaturated and polyunsaturated fatty acid and monensin on gene expression of enzymes involved metabolic pathway of cell proliferation and rumen epithelial intracellular pH regulation. METHODS: Twenty two male Afshari lambs with live body weight of 45 ± 8 kg and six month age were used in a completely randomized design with 3 treatments replicates for 77days including 21 days adaptation period. Experimental diets were consisted of a basal high concentrate diet (16% CP and 2.75 Mcal/kg ME) and 1) no additive (control, C= 8 lambs), 2) 30 mg monensin/day/head during the whole experimental period (T1= 8 lambs), and 3) (polyunsaturated fatty acidduring the whole experimental period (T2 = 6 lambs). Lambs were killed after 77 days on the treatment diets. RESULTS: Compared with the C treatment, relative abundance of mRNA of monocarboxylate transporter isoforms MCT1, MCT4 and the ketogenic enzyme 3-hydroxy-3 methyl-glutaryl CoA-synthase (HMGCS2) were higher for the T1 treatment. The expression of cholesterolgenic enzyme HMGCS1 was down-regulated for the T1 treatment and that of HMGCS1 was up- regulated for the T2 treatment. The expression of MCT1 and MCT4 were down-regulated for the T2 treatment. Monensin had an additional impact on the mRNA abundance of epithelial SCFA- and acid-base transporters with concurrent changes in rumen epithelial thickness. CONCLUSIONS: The results suggest that adding monensin and oil as nutritional means to reduce acidosis cause changes in mRNA expression of VFA transferring proteins and limiting enzyme in the synthesis of cholesterol and Ketone bodies in the rumen epithelium.
اظهر المزيد [+] اقل [-]