مجله تولیدات دامی
سال بیست و پنجم شماره 3 (پاییز 1402)

Identifying of genes with large effects on economically important traits, has been one of the important goal to sheep breeding. Over recent years, advances in DNA-based marker technology have made it possible to identify genomic regions or quantitative trait loci (QTLs) underlying complex traits, such as fleece traits, in sheep. The present study aimed to conduct a genome wide association studies (GWAS) based on gene-set enrichment analysis for identifying the loci associated with wool traits in native Zandi sheep using the 50K arrays.
A total of 300 Iranian Zandi sheep used in this study came from the Zandi sheep breeding station. Wool sampling coincided with the maximum wool growth prior to the shearing of wool. In order to facilitate sampling, sheep were restrained in a lateral position and true wool from the left mid-side site was cut from a 5×5 cm2 close to the skin using regular scissors. Each sample was separately packaged and labeled with ear tag number of the sheep. We measured and recorded four wool production traits: staple length (SL), mean fiber diameter (MFD), fiber diameter coefficient of variation (CVFD), and the proportion of fiber that are equal or more than 30 µm (PR), kemp percentage (KEMP%) and outer coat fiber (OCF) were measured. Genomic DNA extraction from sheep blood was performed by the applying a modified salting out protocol and genotyping of the Sheep SNPChip 50 K SNP Bead from Illumina Inc. The gene set analysis consists basically in three different steps: the assignment of SNPs to genes, the assignment of genes to functional categories, and finally the association analysis between each functional category and the phenotype of interest. Genome wide association study was performed with wool traits using GEMMA software. Using the biomaRt2 R package, the SNP were assigned to genes if they were within the genomic sequence of the gene or within a flanking region of 50 kb up- and downstream of the gene and bioinformatics analysis was implemented to identify the biological pathways performed in GO, KEEG, DAVID and PANTHER databases. The GO database designates biological descriptors to genes based on attributes of their encoded products and it is further partitioned into 3 components: biological process, molecular function, and cellular component. The KEGG pathway database contains metabolic and regulatory pathways, representing the actual knowledge on molecular interactions and reaction networks. Finally, a Fisher’s exact test was performed to test for overrepresentation of the significant genes for each gene-set. In the next step, a bioinformatics analysis was implemented to identify the biological pathways performed in GeneCards databases.
The result from genomic control showed weak population stratification with for woot traits among Zandi sheep population. We identified different sets of candidate genes related to wool traits including: CEP290, PRKCZ, TMTC3, RHPN2, TNFSF4, NLGN1, SPHKAP, PLCE1, FAT1 and PIK3R4 in Zandi sheep. Some of the found genes, are consistent with some of the previous studies related to reproductive traits. According to pathway analysis, 21 pathways from gene ontology and biological pathways were associated with the wool traits (P˂0.05).  Some of the genes were found are consistent with some prior studies and to be involved biological pathways related to hair follicle development, keratinocytes differentiation, synthesizes an enzyme of threonine kinases, development of epidermal and Wnt signaling pathway.
In total, this study supported previous results from GWAS of wool traits, also revealed additional regions in the sheep genome associated with these economically important traits. These findings could potentially be useful for genetic selection in the breeding programs and can be used to understand the genetic mechanism controlling this trait.

Considering that soybean is mainly used in human nutrition and its meal is mostly used in poultry feed, and also due to the high price of soybean meal and its impact on the cost of each kilogram of feed, using of other protein sources such as camellia meal in the diet of fattening lambs can reduce the need of soybean meal for ruminant animals. Previous studies have shown that camelina meal with a suitable percentage of omega-3, crude protein, crude fat and poly unsaturated fatty acids (alpha-linolenic acid) makes it a suitable feedstuff for livestock, poultry and fish. However, due to the presence of anti-nutritional compounds such as trypsin inhibitor and glucosinolate, the limitations of camellia meal should be taken into consideration when used in the diet of animals. In many experiments, it has been determined that camelina is a plant resistant to harsh weather conditions compared to other oil plants, has a high yield potential, and it has been reported that it is possible to plant it in crop rotation with cereals.  In this study, the possibility of using camelina meal (CM) instead of soybean meal (SBM) in the diet of fattening lambs was investigated.

 Twenty-four male lambs aged four to six months with an average weight of 34.21±2.18 kg in a completely randomized design with four treatments and six replications were used. Animals were placed in the individual cages. Treatments included: 1) control (basal diet containing SBM), 2) basal diet with 33% replacement of SBM with CM, 3) basal diet with 67% replacement of SBM with CM, and 4) basal diet with 100% replacement of SBM with CM. Ruminal fluid was taken by esophageal tube and blood samples were taken from the jugular vein on days 0, 45 and the end of the experiment.

 The final weight and daily weight gain were not affected by the replacement of oil meals, but it caused a decrease in dry matter intake (P˂0.05). Ruminal ammonia nitrogen concentration increased in a way that was significant in 33 and 67% replacement (P<0.05). Volatile fatty acids concentration and pH were not affected by treatments. The total population of protozoa and genus Entodinium decreased with the increase in replacement percentage, and according to the interaction effect of time and treatment, the population increased with the increase in the duration of the experiment (P<0.05). The concentration of blood urea increased with the replacement of meals (P<0.05), although this process was influenced by the interaction of treatment and time. With the complete replacement of meals, the concentrations of blood cholesterol and triglycerides increased (P<0.05). Malondialdehyde in the blood of lambs was not affected by replacing SBM with CM. 

 According to the results, camelina meal can be used instead of soybean meal at a maximum level of 67% in diet of fattening lambs.

Minerals affect wool production in sheep by affecting feed intake, altering rumen function and affecting the flow of nutrients from the rumen or by directly disrupting the animal's metabolism. Wool has the highest concentration of sulfur, which indicates the higher need of wool-producing sheep for sulfur than other breeds. The purpose of this study was to investigate the effect of different levels of bentonite sulfur on yield, wool quality, blood minerals, liver enzymes and thyroid hormones of ewes. An experiment was conducted to evaluate the use of different levels of bentonite sulfur in sheep. For this purpose, 18 Dalagh ewes (average weight 38 ± 3.5 kg) were kept individually for 42 days with three treatments and 6 repetitions. Experimental treatments included: 1) control (without bentonite sulfur), 2) treatment containing 0.15 percent of bentonite sulfur and 3) treatment containing 0.3 percent of bentonite sulfur(based on dry matter). At first, to ensure the health of all the ewes, they are subjected to a thorough and thorough examination. The bentonite sulfur used in this research contanied 90% sulfur and 10% bentonite. The diets used in this experiment were prepared and adjusted according to the tables of NRC and were given to the ewes in the morning and evening. Ewes were weighed at the beginning and the end of the period after 16 hours of starvation using a digital scale. In order to determine the quality of sheep's wool, in the initial test, the ewes were arranged uniformly on the 41st day of the experiment, and samples were taken from the left side of the ewes in a 10 x 10 cm format according to the common and standard instructions using a manual wool picker. For determination of blood parameters, on the last day of the experiment, three hours after morning feeding, blood samples were taken from the jugular vein of the ewes. The results obtained from this research showed that with the increase in the level of bentonite sulfur in the diet, the length of fibers, efficiency, strength, kemp and the coefficient of variation of fiber diameter increased (P<0.05). Also, increasing the level of bentonite sulfur increased the concentration of serum sulfur and triiodothyronine hormone (P<0.05). Bentonite sulfur supplementation had no significant effect on final weight, daily weight gain, dry matter intake and feed conversion ratio of ewes. Also, different levels of bentonite sulfur had no significant effect on Non-Medullated fibers, Medullated fibers, average diameter and fiber crude protein. copper gallate, calcium, selenium, phosphorus and serum molybdenum. Addition of bentonite sulfur had no significant effect on serum concentrations of copper, calcium, selenium, phosphorus, molybdenum as well as the concentration of liver enzymes of experimental ewes.  The results of this study indicated that the use of bentonite sulfur up to the level of 0.3% of dry matter, could improve the strength and efficiency of wool fibers and it can be used in feeding ewes without having negative effects on their health and performance.

This study aimed to compare the relative weight of visceral organs, different carcass cuts, the relative length of different intestinal segments, meat quality, hematocrit, and blood metabolites between Arian and Ross308 broiler strains. 

One-day-old mixed-sex broiler chickens from Ross308 and Arian strains were separately allocated to two treatment groups. The initial number of each broiler strain was 48, divided into 12 replicate cages with four chicks each. On days 32 and 42, one bird per replicate was randomly selected (12 broilers from each treatment group), weighed, and killed by cutting the jugular vein with a sharp knife. Then the relative weights of visceral organs and relative length of small intestine segments were determined for both strains. The carcass characteristics and the breast and thigh meat quality (including water-holding capacity, cooking loss, and lipid peroxidation) were assessed only in the birds killed on the 42nd day of age. Some plasma metabolites and hematocrit were also determined after blood collection into heparinized tubes at the end of the rearing period.

The results showed that the total feed intake of Arian broilers was higher than that of Ross 308 (P≤0.05), but no difference was observed in the feed conversion ratio (FCR) between the two strains. The rate of weight gain in the first two weeks was higher in the Arian strain (P≤0.05). However, this trend was reversed during the 5th week of the rearing period. The carcass and valuable cut yields at 42 days of age were higher in Ross308 broilers compared to Arian birds (P≤0.05). On both days of slaughter, the gizzard relative weight was higher in Arian broilers, while the bursa relative weight was lower in this strain compared to Ross308 (P≤0.05). The visceral fat relative weight showed a significant difference between the two strains only at 42 days of age, and it was higher in the Arian broilers (P≤0.05). There was no strain difference in relative weight of the gut and different segments of small intestine at both examined ages. However, the proportion of the jejunum to the total length of the small intestine in the Arian strain was significantly higher than that of the Ross 308 (P≤0.05). Mean plasma uric acid concentrations were significantly lower in Arian compared to Ross 308 (P≤0.05). However, the mean concentration of plasma total triglycerides and hematocrit values were higher in Arian broilers (P≤0.05). The amount of stimulated malondialdehyde in the breast and thigh meat showed higher values in the Arian broilers (P≤0.05), indicating the lower oxidation stability of the chicken meat of the Arian broilers compared to Ross308.

According to the results of the present study, Arian was not competitive with Ross 308 as a well-known commercial broiler strain in terms of the examined parameters. However, by gaining a better understanding of the weekly performance, carcass characteristics, and blood parameters of the Arian strain at different ages and in comparison with the Ross 308, the broiler farmers will be able to adopt the best management and nutritional strategy for raising these native broilers chickens.

Water shortage, low quality soils, and insufficient supply of feed are the main limitations for livestock production in arid and semiarid regions of the word. Therefore, there is a demand to cultivate new crops for these areas as an alternative to crops, which are hypersensitive to low fertile situation. Cultivation of acceptable-quality unusual plants, which are resistant to harsh environmental conditions is a proper way to overcome these challenges. Artichoke (Cynara scolymus L.) is a highly productive crop and produce a large amount of forage per unit of area. Artichoke forage has good nutritional value for ruminant animals. In other hand, artichoke as a medicinal plant contains many secondary compounds including polyphenols, cynarin, chlorogenic acid, carotenoids and natural antioxidants. Lower blood cholesterol and triglyceride and carcass fat have been reported by these compounds in animals fed artichoke products. Therefore, we hypothesized that addition of artichoke forage to diet of fattening lambs may has beneficial effects on their carcass quality traits.
In order to evaluate the effects of dietary artichoke (Cynara scolymus L.) level instead of alfalfa on meat fatty acids profile and carcass quality traits of fattening lambs, this experiment was conducted using 24 Kurdish male lambs (initial body weight of 30.2 ± 2.35 kg) in a completely randomized design with three treatments and eight replications. Experimental treatments included: 1) control (diet without artichoke hay), 2) diet containing 10% artichoke hay, and 3) diet containing 20% artichoke hay. The experiment was lasted for 100 days including 20 d of adaptation period and 80 d of data recording and samples collection. At the end of experiment, all lambs were weighed after an overnight fast (16 h). All lambs were slaughtered, and hot carcass were weighed. The carcass was split into two equal halves (left and right). The right half of carcass was cut into six primal cuts including neck, shoulder, breast-flank, loin, leg and tail. Meat chemical composition, color parameters and fatty acids profile were measured.
The results showed that incorporation of artichoke to the diet improved the daily weight gain of lambs (P<0.05). Also, hot carcass weight and dressing percentage increased linearly with increasing artichoke level in the diet (P<0.05). Dietary artichoke level had no effect on carcass cuts percentage (neck, shoulder, breast flank, loin, leg, and tail), meat chemical composition (moisture, protein, fat and ash) and color parameters (lightness, redness, yellowness). Meat fatty acids profile (including saturated fatty acids, unsaturated fatty acids and conjugated linoleic acids) were not affected by artichoke level in the diets.
According to the results, feeding fattening lambs a diet contained artichoke (up to 20% of total mixed ration) has no detrimental effects on meat quality and improve their dressing percentage.

During many years, with the breeding operations on native hens of Sepahan, growth rate, age of sexual maturity, egg production, egg weight and many other traits of their productive performance have been improved. Estimation of nutritional requirements, especially metabolisable energy and crude protein, is necessary to achieve high fertility and hatchability and produce day-old chicks with appropriate quality. This study was conducted to investigate the effect of different dietary energy and protein on productive performance and egg quality characteristics of the improved indigenous hens in 42-53 weeks of age (during 3 periods of 28 days). Totally, 180 Sepahan hens were assigned to a 3 × 2 factorial arrangements in a completely randomized. Factor 1 was different levels of metabolizable energy (2400, 2550 and 2700 kcal/kg), and factor 2 was levels of crude protein (14 and 16%). Data were collected for feed intake, egg production, egg weight, feed to egg conversion ratio, shell strength, shell thickness, shell weight, percentage of shell weight to egg weight, yolk color index, percentage of yolk weight to egg weight and Hough unit. In addition, during the experimental period, during three stages after artificial insemination, the eggs of Isfahan native breeder hens were collected and after numbering and grading, they were grouped and separated according to the treatment and repetition of the device. Incubators were transferred. At the end of the incubation period, the number of hatched chicks from each replication was counted and group weighing was performed. The components studied at this stage of the experiment also included fertility efficiency, hatchability, day-old chick weight and percentage of chick weight to hatchable eggs. According to the results of the present experiment, in the whole experimental period, feed intake, egg weight and egg production were not affected by experimental treatments (P<0.05). Egg mass weight in chickens fed diets containing 2550 kcal was significantly higher than chickens fed diets containing 2400 kcal (P <0.05) and feed-to-egg conversion ratio in native hens, fed diets containing 2550 kcal was lower than 2400 kcal (P <0.05). The highest egg shell strength (3.4 kg/cm2) was in diets containing 2700 kcal energy and 14% crude protein and the lowest (3.02 kg/cm2) was in diets containing 2400 kcal energy and 14% crude protein (P<0.05). By increasing crude energy levels, the color of egg yolk also increased (P <0.05). Increasing the level of crude protein in the diet decreased Hough units of eggs (P <0.05). The highest rate of fertility and hatchability of hatchable eggs was obtained in treatments containing 2550 kcal of energy (P<0.05). Experimental treatments had no significant effect on the weight of day-old chicks (g) and the ratio of chicken weight to the weight of hatchable eggs. However, fertility (percentage) and hatchability rates of fertile eggs (percentage) were affected by different energy levels (P <0.05), so that the highest fertility rate was in treatments received 2550 kcal ME/kg of diets. Different levels of crude protein and energy and protein interactions had no significant effects on these traits. Embryo mortalities in the first and second weeks of the incubation period (percentage) were not affected by experimental treatments, but embryo mortalities in the third week and in the whole incubation period were affected by the interaction of energy levels and crude protein in the diet (P<0.05). In general, based on the results obtained under the conditions of this study, it seems that the diet containing 2550 kcal metabolisable energy and 14% protein is appropriate for feeding to Isfahan native breeder hens during the laying period.

Exposure of poultry birds to extreme temperature stressor modulates the immune responsiveness and haemato-biochemical parameters of birds. Cold temperature can increase ascites susceptibility by increasing both metabolic oxygen requirements and pulmonary hypertension. Biochar is an ash substance that is produced from the burning of biological material via pyrolysis. This study was carried out to investigate the effects of wet Litter Biochar on performance of cold-stressed broiler chickens.

In this experiment, the effect of wet litter biochar (WLB), probiotic and zeolite on performance, blood metabolites and small intestine morphology of broiler chickens reared under cold stress were investigated. In a completely randomized design 350 Ross-308 broiler chickens (one-day-old, mixed sexes) were allocated to seven treatments, five replicates and 10 birds in each replicate. Experimental treatments included: 1) positive control (basal diet in recommended temperature), 2) negative control (basal diet+ cold stress), 3) negative control+ %0.5 WLB, 4) negative control+ %0.75 WLB, 5) negative control+ 1% WLB, 6) negative control+ 0.02% probiotic Ecobacto-P, and 7) negative control+ 1% zeolite. In cold stress groups, house temperature decreased to 17° C from 7 d until end of the experiment (42 d).

As compared to group reared in recommended house, cold stress significantly decreased broiler chickens feed intake, body weight gain (BWG), carcass and abdominal fat percentages, serum triglyceride concentration, activity of aspartate transaminase and alanine aminotransferase enzymes as well as villous width of jejunum and ileum while increased total and ascitic mortality, ileal and jejunal villous height and crypt depth to villous length ratio (P<0.05). Inclusion of 0.5 and 1% WLB and probiotic increased broiler chickens BWG, ileal and jejunal villous length and surface area, but decreased feed conversion ratio as compared to negative control group (P<0.05).

Generally, although addition of wet litter biochar and probiotic led to improvement in performance and small intestine morphometry of cold-stressed broiler chickens, but they did not completely catch-up negative effects of cold stress on broiler chickens.

 This study investigated the pelletization ability of green pistachio shell residues, its effect on anti-nutrients, and several physical and mechanical properties of pistachio shell pellets produced with an industrial and custom-made pelletizing machine. In this experiment, the designed device was utilized with pistachio green shell residues containing 15% moisture, 1 mm particle size, and a temperature of 65 °C. To improve adhesion and reduce antinutritional substances of pistachio residues, bentonite, wheat, urea, and molasses were used at 3, 6, 4, and 5 kg, respectively, per 100 kg of pistachio residues. The density, maximum breaking force, breaking energy, phenolic compounds, tannin, acid detergent insoluble fiber (ADF), (NDF) of the pellets produced were determined. Furthermore, the maximum breaking force and breaking energy of the pellets produced by the machine for testing biological materials were measured. The Student's t-test was used to analyze statistically the parameters measured in the pellets produced by two Peltzen machines. The research results showed that the density of pellets produced in the industrial machine was significantly higher than in the custom-made machine (p<0.05). Conversely, the breaking energy of the produced pellets in the custom-made machine was higher than in the industrial device (p<0.05). The amount of phenolic compounds, tannin, ADF, and NDF for the designed Peltzen device was 19, 26, 12, and 10% less than the industrial Peltzen device, respectively (p<0.05). In general, it can be concluded that the designed device improves the quality and reduces antinutritional substances in the pellets of green pistachio shells.