زمینه و هدف: مصرف مکمل‌های سلنیومی در تغذیه دام به دنبال افت عملکرد ناشی از کمبود سلنیوم جیره، بسیار مقرون به صرفه است. با پیشرفت فن‌آوری‌های تغذیه‌ای، محصولات جدید مکمل‌های سلنیومی مانند نانوسلنیوم دردسترس بوده، که نیازمند تحقیق و مقایسه با محصولات پیشین است. لذا هدف از پژوهش حاضر بررسی اثرات تغذیه منابع مختلف سلنیوم بر عملکرد، متابولیت‌های خونی و پاسخ ایمنی در گوساله‌های هلشتاین و دورگ هلشتاین-مونت بیلیارد است. روش کار: تعداد 24 رأس گوساله شیرخوار هلشتاین و دورگ هلشتاین-مونت بیلیارد با میانگین وزنی 1±43 کیلوگرم، در قالب طرح کاملاً تصادفی مختلط، به مدت 75 روز بررسی شد. تیمارهای آزمایشی شامل: 1-جیره پایه بدون مکمل سلنیوم (دورگ هلشتاین-مونت بیلیارد)، 2-جیره پایه بدون مکمل سلنیوم (هلشتاین)، 3-جیره پایه + 3/0میلی‌گرم مکمل نانوسلنیوم در هر کیلوگرم ماده خشک (دورگ هلشتاین‌- مونت بیلیارد)، 4-جیره پایه + 3/0میلی‌گرم مکمل نانوسلنیوم در هر کیلوگرم ماده خشک (گوساله‌های هلشتاین)، 5-جیره پایه + 3/0میلی‌گرم مکمل معدنی سلنیت سدیم در هر کیلوگرم ماده خشک (دورگ هلشتاین‌-مونت بیلیارد)، 6-جیره پایه + 3/0میلی‌گرم مکمل معدنی سلنیت سدیم در هر کیلوگرم ماده خشک (هلشتاین) بودند. مصرف خوراک و وزن بدن، گلوکز، کلسترول، تری‌گلسیرید، پروتئین‌کل، اوره، گلوتاتیون پراکسیداز، لنفوسیت، نوتروفیل و مونوسیت خون اندازه‌گیری شد. یافته‌ها: منابع مختلف سلنیوم بر عملکرد و فراسنجه‌های خونی گلوکز، کلسترول، تری‌گلسیرید، اوره و پاسخ ایمنی گوساله‌ها تأثیر معنی‌داری نداشت. اما پروتئین‌کل خون و فعالیت آنزیم گلوتاتیون پراکسیداز افزایش یافت. نوع مکمل در میزان فعالیت آنزیم گلوتاتیون پراکسیداز تأثیری نداشت. نتیجه‌گیری: نوع مکمل سلنیومی بر عملکرد و پارامترهای خونی گوساله‌های هلشتاین و هلشتاین-مونت بیلیارد تأثیرگذار نبود. تفاصيل المقالة

Bovine tuberculosis is one of the serious public health challenges which also causes economic damage in the livestock industry. Understanding the interaction mechanism between the host immune system and the causative pathogen of tuberculosis is one of the essential areas of study for success in designing effective drugs to treat tuberculosis. Here, we used four publicly available microarray data to light up the response of the cattle immune systems to Mycobacterium bovis at the gene level. Our integrating analysis results on microarray data led to identifying 189 (160 up- and 29 down-regulated) differentially expressed genes for infected samples with Mycobacterium bovis against uninfected samples. Gene ontology and pathway analysis indicated that most of the differentially expressed genes are related to the immune system's (especially innate immune system) response to the pathogen. Finally, 122 proteins (108 up-regulated and 14 down-regulated) were included in the constructed protein-protein interaction network among the proteins from differentially expressed genes. We identified 11 genes as hub genes based on three methods using the cyto Hubba plug-in in the Cytoscape. Based on our analysis, most differentially expressed genes are related to the innate immune system. However, considering the impact of time on the microarray data analysis indicated that associated gene expression with the adaptive immune system increased by time. تفاصيل المقالة

The myogenic factors (MYF) 5 gene has been reported to contribute to muscle growth and development, therefore they are considered as candidate genes for growth and meat quality related traits. The MYF5 gene is expressed during proliferation of myoblasts and comprises 3 exons. To ascertain whether there is any variation in the camel MYF5 gene, we have used a polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) method for the analysis. In this study, coding region (exon 1) of the MYF5gene was investigated. Four unique SSCP patterns were detected in exon 1. Two Single nucleotide polymorphisms (SNPs) were detected - A/G and G/A in 98 and 366 position, respectively that create four haplotype, related to banding patterns. The variations detected in this study leads to a serin/asparagine and tryptophan/stop codon amino acid changes, respectively and could be considered for the development of gene-assisted selection in camel breeding. تفاصيل المقالة

The effects of increasing the laying period day-length from 13 to 16 hours were examined in Ross (308) broiler breeders. The birds reared on 8-h photoperiods and then were photo-stimulated at 21 weeks by increasing the photoperiods from 8 h of light, 16 h of darkness (8L:16D) to 11L:13D. Then the birds were given an additional 60 min of light per week cumulatively, such that in different experimental groups the 12L:12D, 13L:11D, 14L:10D, 15L:9D and 16L:8D photoperiods were achieved in 22, 23, 24, 25 and 26 weeks of age, respectively. The photoperiods remained unchanged until the experiment was finished at 50 weeks of age. The 16L:8D group had a poorer feed conversion and less egg production and egg mass than the other 3 groups (P<0.05). The total settable egg percentage was significantly lower for 15L:9D and 16L:8D than for 13L:11D and 14L:10D birds (P<0.05). The 13L:11D and 14L:10D h hens had more double-yolked and broken or abnormal eggs, followed by the 15L:9D h birds, and the 16L h birds (P<0.05). The mean egg weight of 14L:10D birds was significantly more than for 16-L h birds (P<0.05), with 13L:11D and 14L:10D birds were intermediated (P<0.05). The percentage of hatchability was higher in 13L:11D h hens followed by the 15L:9D and the 16L:8D birds (P<0.05), with 14L:10D h hens intermediated between 13L:11D and 15L:9D groups. The findings of this study suggest that 13L:11D was the optimal photoperiods for Ross 308 broiler breeders in the laying period up to 50 weeks of age. تفاصيل المقالة

β-lactoglobulin is one of the important milk proteins in several ruminants like goats, sheep and cattle. This study was performed to investigate the genetic polymorphism of exon 7 and 3’ UTR region of β-lactoglobulin (BLG) gene and its association with milk composition in 120 unrelated individuals of Iranian indigenous Khalkhali goats. Purified polymerase chain reaction (PCR) products (427 bp) were sequenced under standard conditions using Sanger sequencing. Alignment of sequenced fragments against reference sequence leads to identification of one single nucleotide polymorphism (SNP), substitution A (frequency equal to 0.44) to C (frequency equal to 0.56) in the 3’ UTR region of BLG gene. Observed frequencies of AA, AC and CC genotypes were 0.12, 0.64 and 0.24, respectively. The effects of identified genotypes on milk composition were analysed using general linear model. We found that BLG gene genotypes have a significant effect on milk parameters except for lactose percentage (p < 0.05). The milk of goats with AA and AC genotypes had higher protein and fat percentages, respectively, in compaired with other genotypes (p < 0.05). Obtained results revealed that, identified genotypes in the BLG gene of Khalkhali goats is not in Hardy-Weinberg equilibrium. تفاصيل المقالة

Karakul (KAR) is one of the resistant sheep breeds to harsh desert conditions, which is also known for its excelent lamb pelt quality. This study was performed to identify the signature of selections in the KAR breed using whole-genome sequencing data (WGS) compared with five other Iranian native sheep. Three methods, including population differentiation index (Fst), nucleotide diversity (π), and cross-population extended haplotype homozygosity (XP-EHH) applied to detect the genomic signature of selection. Data analysis leads to identifying 38 shared genes among three methods as positively selected genes for the KAR breed. The most of mentioned genes were associated with coat color (KIT, DVL3, YPEL3, ERBB4, ZNF451, and CTSO), fat and energy metabolism (GDPD3, STARD13, ZNF106, MAPK3, RGS6, PHYH, AP2M1, SPAG9, DNAH9, NDUFAF6, and ARSK), muscle function (MYOCD and MCTP1), growth (CPNE4), altitude adaptation (DNAH9 and SERGEF), and reproduction (TBX6, PHYH, SPAG9, and ARSK). Based on our results, these candidate genes may have a positive effect on the adaptation of the KAR breed to a desert environment. تفاصيل المقالة