مجله تولیدات دامی
سال بیستم شماره 2 (تابستان 1397)

The aim of this study was cloning of the beta subunit of human chorionic gonadotropin in an appropriate vector for production of transgenic chicken trrough sperm mediated gene transfer. In this regard, transgenic chicken production tecnology has taken into consideration for having many advantages such as short generation times, the large number of production of offspring and suitable pattern of protein glycosylation. To date, no study has been conducted on the cloning of the beta subunit of human chorionic gonadotropin for rooster sperm. For this purpose, the hormone beta subunit were amplified by a specific primer pairs, and cloned in T vector. The recombinant plasmid was transformed into Competent E. coli cells and colonies that containing recombinant plasmids were selected by colony PCR.The validity of extracted plasmid were analyzed by enzyme digestion and sequencing. The beta chain of T vector was isolated and was cloned again into pcDNA3.1 + expression vector. The results of enzyme analysis and sequencing indicated that recombinant plasmid pCDNA3.1 +/βhCG were cloned with the correct sequence and completely matched up with human chorionic gonadotropin beta subunit gene that can be concluded that it has sutible stracture for sperm mediated gene transfer.

Selection of live animals with minimum carcass fat in animal breeding programs will lead to increase in meat production at national level. The ligands of Wnt genes are of the effective factors in adipocyte cell differentiation. This study was aimed to assess the association between polymorphisms in Wnt10a and Wnt10b genes and carcass traits in 96 Afshari – Booroola Merino male lambs. In this study, DNA was extracted from blood samples using phenol-chloroform extraction method and polymerase chain reaction was performed for amplification a 663 bp fragment of exon III and a part of the second intron of Wnt10a gene and a 512 bp fragment of exon III Wnt10b gene. The results showed a polymorphism and three monomorphisms (a different allele compared to reference sequence of the gene) in the Wnt10a gene but all the sequences of the Wnt10b fragment were the same in studied region of the gene. Results of the sequencing lead to identification of four single nucleotide changes in Wnt10a gene in the studied area when compared to the reference sequence. One of the monomorphisms was in the intron and among other three nucleotide changes identified in exon III one was a missense in codon 139. After digestion with restriction enzymes HpaII at this codon, it was observed that all sampled lambs had mutant homozygous genotype compared to the reference sequence. This site was also evaluated in a number of Afshari (fat- tailed) and Zell (with the least fat tail) but again the same results were observed. Therefore, it seems that in this position the G is the wild type allele in the studied population.

Heat stress is one of the most important environmental stressors challenging poultry production worldwide, especially in warm regions such as Sistan and Baluchestan province of Iran. Heat stress increases the production of free radicals in the chicken’s body. Glutathione peroxidase plays important roles as cellular antioxidants in heat stress. The aim of this study was to conduct an analysis of the evolutionary and phylogenetic of GPX-1 in Ross 308 and Khazak populations. Boold samples were collected from 10 birds selected randomly from two stocks of Khazak and Ross 308 population (5 Ross 308 and 5 Khazak birds). DNA was extracted from whole blood. PCR amplification of 800 bp of GPX-1 was performed using one pairs of special primers. Then, PCR product sent for DNA sequencing. Sequence alignment of the GPX-1 fragment revealed a total of 9 haplotypes and 13 variable sites. Out of 13 polymorphic sites, 5 were singletons. Dendrogram of phylogenetic showing genetic similarity between the two populations, but probably diversity within populations indicate the possibility to improve genetic changes and increase the resistance to environmental stresses using selection. The results of genetic distance and polymorphic site of GPX-1 in different species approved phylogenetic tree findings. Study of positive- selection process showed that selection and evolution are playing major roles in understanding the biological function of this gene

The objective of this study was to evaluate the effects of different doses of pistachio by-products (PBP) tannin extracts obtained by water, ethanol 70 % and methanol 80 % on the soybean meals protein protection from ruminal degradability. Soybean meal supplemented with 0.5 and 1 % tannins of different tannin extracts of PBP. Ruminal degradability and disappearance of dry matter and crude protein in untreated soybean meal (control) and soybean meal treated by tannin extracts (6 treatments) was determined in an in situ trial (three head of castrated Taleshi male calves) and post ruminal disappearance was measured in DaisyII incubator. Soybean meal supplementation with 1 % tannin from water extract, 0.5 and 1 % tannin from ethanol and methanol extracts decreased the ruminal protein disappearance (P<0.01) without any negative effect on total gastrointestinal disappearance of dry matter and crude protein. Also, the addition of all of tannin extracts to soybean meal reduced (P<0.01) the concentration of rapidly degradable proteins. In conclusion, the results showed that tannins of water, ethanol and methanol of PBP extracts could be effective on soybean meals protein's protection from ruminal degradability; however, the use of tannin from water extract of PBP can be more economical and practical.

This study was conducted to evaluate the effects of dietary substitution of different levels of Maize silage (MS) with Jerusalem artichoke aerials part silage (JAAPS) on feed intake, digestibility and microbial protein syntheses in twenty Chall male sheep (live body weight of 65.3±2.3 kg). Four iso-energetics and iso-nitrogenus diets (forage-to-concentrate ratios; 64:36) were formulated in which MS was replaced by different levels (0, 180, 360, or 540 g/kg dietary DM) of JAAPS. The diets were fed to four experimental animals groups in a completely randomized design for a 31-days period. Dry matter intake and dry matter digestibility were 2139 and 699 in control diet and 2095 g/day and 697 g/kg DM in diet contains 540 g/kg DM JAAPS respectively. The replacement of MS by JAAPS did not affect dry matter intake and nutrients intake. Digestibility of dietary nutrients was not affected by experimental diets. By replacing the JAAPS instead of MS, there was no significant statistical change in the microbial protein synthesis. It is concluded that the partial substitution of MS for JAAPS, up to 540 g/kg DM, in diet of sheep has no adverse effect on feed intake and diet digestibility. So the Jerusalem artichoke aerial parts could be used as a silage in sheep diets.

Extract of Scrophularia striata (ES) was tested as a feed additive for improving the efficiency of ruminal degradation of nutrients, concentration of total phenolic and flavonoid compounds and antioxidant activity using the rumen simulation technique (RUSITEC). Twelve fermentation units (vessels) were set up for 2 experimental runs each lasting 10 d wherein the last 5 days served for sampling. Treated vessels were supplied with no additive (Control), 10 mg/d monensin (Monensin), and 480 and 960 mg/d of ES, respectively. Both levels of ES and monensin decreased methane production expressed per gram nutrients degraded (P<0.05). Production of total volatile fatty acid per gram DM and organic matter degraded was higher in ES treatments in comparison with control and Monensin (P<0.05). The ammonia production expressed per gram CP degraded was lower than control only in the high level of ES supplementation (P<0.05). The latter treatment also resulted in the highest concentration of total flavonoid, phenol lic compounds and antioxidant activity compared to other treatments (P<0.05). Based on the present results, ES could be considered as an alternative to antibiotic for improving the efficiency of degradation, increasing ruminal antioxidant activity and decreasing methane production.

To evaluate the effect of feeding yeast probiotic in milk or starter on growth, fecal score, health, blood and rumen parameters, 30 female Holstein calves with average 40.4±1.8 kg birth weight in Taliseh Nemouneh dairy farm used from 14 until 65 days old. Calves randomly divided to 3 treatments including: 1) control (without probiotic) 2) yeast probiotic in starter 3) yeast probiotic in milk. Average daily gain, body weight and feed efficiency were not significantly different between treatments. Dry matter intake was significantly lower in treatment 2 than control (P<0.01). Digestibility of feed nutrients, ammonia nitrogen concentration, rumen fluid pH and blood parameters did not affected by treatments. Fecal score and health in treatment 2 and 3 were better than control. Generally, calves were fed with yeast probiotic in milk had the best fecal score and health

The purpose of this experiment was to evaluate the effect of probiotic and peribiotic supplements on performance of Holstein dairy cows. For this purpose, 40 Holstein dairy cows with daily milk production of 33 ± 0/8 kg and initial weight 700 ± 40 kg were divided into four groups in a completely randomized design. The experimental treatments consisted: 1- control group (basic diet) 2- probiotic group (base diet + 4 gr probiotic per head per day) 3- prebiotic group (base diet + 14 gr perbiotypes per Ross per day) 4- Synbiotic group (base diet + 4 gr probiotic + 14 gr perbiotic per head per day). The results of this experiment showed that there was a significant difference between the average duration of chewing, rumination and eating among different diets (P <0.05). The most duration of chewing, rumination and eating belonged to the group that consumed probiotics and had a significant difference with other groups (P <0.05). Probiotics consumption increased the amount of daily milk production, milk production with 3.5% fat and milk production with 4% fat, and a significant difference (P <0.05) with the control group (basal diet without additive). Feed efficiency increased in supplementary rations and resulted in a better performance of probiotic diets. Health indicators, consistency and fluidity of stool in supplementary diets have also improved.

The effect of two thyme species hydroalcoholic extracts and flavomycin on nutrients digestibility and antioxidant status of male broilers was assessed in a 42-day trial using 128-day-old Ross 308 chicks by employing a completely randomized design with four treatments and four replicates. The experimental treatments consisted of control, 0.05 percent Thymus daenensis extract, 0.05 percent T. kotschyanus extract and 0.1 percent flavomycin. Throughout the experiment, the chickens on flavomycin diet had a better weight gain and feed conversion ratio (P<0.05). Although thyme diets had no effect on weight gain, the birds on diet containing T. daenensis extract had better feed conversion ratio than those on the control diet (P<0.05). The jejunal villus height and villus height to crypt depth ratio increased in birds fed with diets containing T. daenensis extract and flavomycin (P<0.05). However, villus surface area of jejunum was increased in birds on diets containing the additives (P<0.05). Feeding chickens with diets containing T. daenensis extract and flavomycin decreased the thickness of muscle layer of jejunum (P<0.05). Digestibility of dry matter and organic matter was increased by T. kotschyanus extract and flavomycin (P<0.05).Nitrogen retention was increased in birds fed with all additives (P<0.05). The activity of blood superoxide dismutase and glutathione peroxidase in birds receiving thyme extract was higher than those of the control group (P<0.05). Malondialdehyde of thigh meat declined in birds receiving diets containing T. kotschyanus extract in comparison with other treatments (P<0.05). Based on the results of the study such as improved feed conversion ratio, intestinal mucosal morphometry and body immune status parameters, application of 0.05 percent T. daenensis extract can be suggested as a growth promoter in broiler diets.

The present study was carried out to investigate the effect of clove essential oil nanoemulsion (CEON) on performance of broiler chickens fed wheat-based diet. A total of 280 day-old broiler chicks (Ross 308, mix sex) were used in a completely randomized design with seven treatments and four replicats. The experimental treatments were; 1- control, 2- control supplemented with enzyme (En), 3- control supplemented with 200 mg/kg clove essential oil (CEO) and 4 to 7 were control supplemented with 200, 150, 100 and 50 mg/kg of CEON, respectively. The results of this experiment showed that in the whole rearing period, the feed intake and body weight gain of birds fed diets supplemented with 200 mg/kg CEON decreased significantly compared with control and En treatments (P≤0.05). In the whole period of experiment, chicks fed diets supplemented with CEO and 50 mg/kg CEON had better feed conversion ratio compared with control group (P≤0.05). Serum triglyceride concentration decreased significantly in chicks fed diets containing different levels of CEON compared to En treatment (P≤0.05). Relative weight of bursa increased in chicks fed diets containing CEO and 200 mg/kg CEON in comparison with control treatment. Supplementation broiler diets with CEO and 200, 150 and 100 mg/kg CEON decreased significantly Escherichia coli populations of cecal content (P≤0.05). According to the results of this experiment, supplementation broiler wheat-based diets with CEON may decrease Escherichia coli populations of cecal content.

The insulin resistance and glucose, insulin, IGF-1 metabolism (somatotropic axis performance) were investigated in cows to receive (4 g yeast/d/head) (Probio-Sacc®, BioChem, GmbH, Germany) or not receive live yeast supplement from 21 d before expected date of calving under the hot months of summer (THI = 82). Two groups of 6 periparturient Holstein cows were fed a diet without or with 4 g yeast/d/head (15*109 CFU/g) starting 21 d prepartum through 8 weeks postpartum to investigate the changes of blood concentrations of glucose, insulin, IGF-1 and glucose tolerance test (GTT). On d 60 postpartum, greater blood levels of glucose, insulin and insulin-like growth factor I were found in cows receiving yeast supplement than those receiving no yeast (P<0/05). Probiotic had not significant effect on GTT test. Overall, it appears that Probiotics would beneficially improve the blood concentrations of glucose, insulin, IGF-1 in day 60 postpartum (on DFS day) and improve somatotropic axis of dairy cows during the heat stress. Probiosac probiotic had positive effects on somatotropic axis and animal performance. It’s can be a good solution to increase dairy cow’s performance in heat stress condition.

This study was conducted to investigate the differentiation potential of equine adipose-derived mesenchymal stem cell into bone in single-dimensional culture system (in plastic tissue culture) and in three-dimensional system (on poly-l-lactic acid scaffolds; PLLA). A porous structure that allows use of three-dimensional distribution and provides optimal growth of cells is of great clinical significance in the field of tissue engineering. In current study using equine adipose-derived stem cells (ASCs), we intended to compare the osteogenic differentiation potential of PLLA nanofibrous scaffold with tissue culture plastic (TCP). Adipose tissues were collected from 3 adult horses, and ASCswere isolated by enzymatic digestion. PLLA nanofibrous scaffold was successfully prepared using a phase separation method. Viability and growth characteristics of ASCs on TCP and scaffold were investigated by tetrazolium (MTT) based colorimetric assay. Alizarin Red staining was performed for determination of calcium deposition following osteogenic differentiation. Furthermore, other common osteogenic markers such as alkaline phosphatase (ALP) activity, and calcium content were also analyzed. Our data showed that the PLLA scaffold had no detrimental effect on the cell growth rate as evaluated by MTT assay. However, ASCs that differentiated on PLLA nanofibrous scaffolds indicated higher ALP activity and more calcium content than that on TCP. Adequate proliferation rate and higher expression of osteogenic markers of stem cells cultured on PLLA nanofibrous scaffolds provide this scaffold as a suitable substrate to support proliferation and differentiation of ASCs in equine.