مجله پژوهش در نشخوار کنندگان
سال دهم شماره 2 (تابستان 1401)

Today, the nutritional value of microalgae is not hidden from anyone, and extensive research is being done to increase their production capacity and nutritional value. Due to the high cost of the protein portion of livestock diets, microalgae can be economically viable natural alternatives to protein supplements such as soybean meal in competitively priced diets. In all of the dietary amino acids, lysine and methionine are the first and second limiting amino acids. Most microalgae species contain relatively high levels of lysine. But they are somewhat deficient in sulfur-containing amino acids such as cysteine and methionine. The present experiment aimed to investigate the protein content and chemical composition of two species of microalgae, Isochrysis galbana (I. galbana) and Nannochloropsis oculata (N. oculata), the degree of nitrogen degradability (IVDN), and their different parts of the protein in the Cornell Net Carbohydrate and Protein )CNCPS( system.

For this purpose, after culturing and harvesting the two microalgae species in the laboratory and conducting experiments, the amount of dry matter (DM) composition, ash, crude protein (CP) and determination of amino acid pattern, evaluation of IVDN and determination of different parts of the protein of two species of microalgae I. galbana and N. oculata was made by CNCPS system. In this study, to estimate the IVDN, the ruminal fluid of three male Holeshtine castrated fistula calves with an average weight of 480 ± 40 kg and age 2 years was used.

The results showed that the two microalgae species were different in terms of CP%, fat %, and NSC % (P<0.05). The N. oculata 37% and I. galbana had 32% CP. The ratio of essential to non-essential amino acids was 18.79% in I. galbana and 28.8% in N. oculata (P <0.05). The percentage (IVDN) at 8, 12, and 24 h of incubation in I. galbana was 44%, 53%, and 48%, respectively, and in N. oculata was 35%, 40%, and 38% (P <0.05). The percentage of RUP at 8, 12, and 24 h of incubation was 56%, 47%, and 42% in I. galbana and 65%, 60%, and 62% in N. oculata, respectively. Sections A, B1, B2, and C in I. galbana 10.07, 8.85, 66.18, 7.56, and in N. oculata 15.16, 16.64, 54.98, and 8.8, respectively (P <0.05).

The results of the present study indicated that considering the amount of fat%, CP%, IVDN, and RUP in N. oculata and I. galbana, it seems that these microalgae are suitable for use in animal feed.

Fattening operations play an important role in the supply of animal protein, which in addition to producing more meat, the quality of meat also improves, because proper nutrition and the use of proper fattening methods accelerate the growth and improve the quality of meat. In order to achieve optimal and economical production in sheep breeding, a nutritional program must take into account the nutritional needs of livestock, the quality of food and their consumption time. However, due to the reduction of forage and pastures in Iran, the farmer is forced to use more concentrate in the diet. The aim of this study was to investigate the effects of fiber reduction and alfalfa removal on feed intake, body weight, feed conversion ratio and carcass characteristics of Afshari male lambs.

The present study was performed using 36 Afshar male lambs with a mean live weight of 32.53 ± 1.9 kg and a mean age of 93 ± 6.63 days for 90 days based on a factorial experiment based on a completely randomized 2×2 design. Experimental treatments include treatment of frist: fattening diet containing 80% concentrate and 20% forage (10% wheat straw and 10% alfalfa), second treatment: fattening diet containing 80% concentrate and 20% forage (20% wheat straw and 0% alfalfa), third treatment: fattening diet contained 90% concentrate and 10% forage (5% wheat straw and 5% alfalfa) and fourth treatment: fattening diet contained 90% concentrate and 10% forage (10% wheat straw and 0% alfalfa). The lambs were fed three times a day at 8.00, 14.00 and 20.00 for ad libitum. At the end of the feeding period, all lambs were weighed after 16 h feed deprivation and four lamb from each treatment was slaughtered. The data were analyzed using Spss21 and Excel.

There was a significant difference between different treatments in terms of weight gain. Treatment four with 90% concentrate and 0% alfalfa had the highest (300 g) and treatment one with 80% concentrate and 10% alfalfa produced the lowest daily weight gain (200 g) in lambs. With increasing concentrate and removal of alfalfa, feed consumption increased so that the highest amount was related to treatment four (1.830 g) and the lowest was related to treatment one (1.476 g). Treatment four had a numerically lower conversion ratio (6.1) compared to the other three treatments. The mean final weight of lambs, hot and cold carcass weights showed significant differences between experimental treatments.

According to the results, the removal of alfalfa did not cause any production problems in these areas. Increasing the concentrate and eliminating alfalfa in the diet increases feed intake and daily weight gain and overall higher final weight in fattening periods and also improves feed conversion ratio, growth performance and carcass percentage.

Increasing glucose supply in the small intestine may be effective in improving the physiological status of dairy cows, and it is hypothesized that glucose supply in the small intestine increases whole body glucose supply and then improves the liver function of dairy cows during the early lactation. The aim of the present experiment is to produce a Rumen-Protected Glucose product and evaluation its effects on milk production and dry matter intake of fresh Holstein dairy cows.

In this study, the matrix and true encapsulation method was used to produce Rumen-Protected Glucose. Hydrogenated fat was used as the matrix for matrix encapsulation. For the true encapsulation coating method, the dextrose powder was first converted into 1-3 mm granules and then completely coated. In order to evaluate the rumen degradability of encapsulated glucose, three cows with ruminal cannula were used. In order to investigate the effects of produced Rumen-Protected Glucose, 16 fresh cows were used in a completely randomized design with two treatments and 8 cows in each treat. The diets of both treatments were exactly the same, except that the cows in Rumen-Protected Glucose treat received 600 g of Rumen-Protected Glucose daily as top dresesd, and the cows in control treat received the same amount of coating material and dextrose. Rumen-Protected Glucose was fed from day 4 to 30 after calving. The cows were kept in individual boxes and milk production and dry matter intake were recorded daily.

Matrix encapsulation failed to adequately protect glucose from rumen degradation. Using the true encapsulation method, a Rumen-Protected Glucose source with suitable degradation resistance (approximately 50% passing) and high intestinal digestibility (95% intestinal digestion) with a ratio of 70% active ingredient and 30% coating material was produced. Feeding 600 g of Rumen-Protected Glucose had no significant effect on dry matter intake (17.76 kg/day in Rumen-Protected Glucose treatment and 17.43 kg/day in control treatment; P>0.48) and milk production (33.58 kg/day in Rumen-Protected Glucose treatment and 33.95 kg/day in control treatment; P> 0.78). The effect of time on milk production was significant in both treatments (P < 0.005). However, the effect of time on dry matter consumption was not significant (P>0.31). Milk fat was increased in cows received Rumen-Protected Glucose (4.94% in Rumen-Protected Glucose treatment and 4.29% in control treatment, P< 0.033).

A source of Rumen-Protected Glucose with suitable degradation resistance (about 50% passing) and high intestinal digestibility (95% intestinal digestion) was produced. Feedig of Rumen-Protected Glucose to fresh dairy cows improved their glycogenic status and reduced nutrient transfer for milk production.

Tail in sheep is a valuable energy source. However, in modern intensive and semi-intensive sheep industry the lean-tailed sheep breeds have more desirable and marketable. Therefore, due to the negative effect of tail size on production efficiency, researchers are looking for methods to eliminate this trait. Identification of genes involved in the process of fat deposition in tail is necessary for reducing tail size in sheep. Several genomic methods such as genome-wide association and selection signature studies or gene expression analysis for describing a possible genetic background for deposition of fat in various fat-tail breeds have been used. The aim of this study was to identify effective genes in fat-tailed sheep breeds (Afshari and Sunite) compared to breeds without tail (Dorper and German Mutton) using selection signature and gene ontology methods.

In this study, genotype information of 366 sheep (37 Afshari, 69 Sunite, 99 Dorper and 161 German Mutton) genotyped with Illumina Ovine SNP50K BeadChip genome arrays, were used. The XP-EHH method using R software package version 1.9 was used to identify selection signature. Genomic version Oar_v4.0 database NCBI was used for detecting the genomic position of SNPs in sheep genome. Candidate genes were identified by SNPs located at 1% upper range of XP-EHH using Plink v1.9 software and gene list of Illumina in R. Additionally, the latest published version of Animal genome database was used for defining QTLs associated with fat deposition traits in identified locations.

Based on the results of XP-EHH, 18 common genes were identified from comparing Afshari population with German Mutton and Dorper breeds, in which five genes (LOC114116389, LOC114118754, KCMF1, TCF7L1 and RASSF2) were associated with QTLs related to fat deposition including carcass fat percentage, internal fat amount and fat tail deposition. 15 common genes were also identified from comparing Sunite population with German Mutton and Dorper populations, in which two genes (SEMA5B and CDH9) were associated with QTLs related to fat deposition. The results of gene ontology showed that some of these genes play effective roles in signaling Wnt, growth, development and morphology of cells.

based on the results of selection signature using XP-EHH method in Afshari and Sunite breeds, RASSF2 gene was identified as a selection signature in Afshari breeds. This gene was also related to tail fat storage QTL, which was identified for the first time in this study. LOC11411689 and LOC114118754 genes related to carcass fat percentage QTL, KCMF1 and TCF7L1 genes related to the QTL of internal fat amount in Afshari breed were also identified. In addition, the SEMA5B gene associated with the QTL of carcass fat percentage and the CDH9 gene associated with of subcutaneous fat weight were identified in the Sunite breed. The results of this study could be used in sheep breeding programs to reduce fat deposition in tail, especially for Afshari breed.

Barley is always the common grain used in sheep fattening feed, as the only source of starch, but due to the rapid fermentation of barley in the rumen, which may lead to increased digestive problems such as ruminal acidosis and thus reduced performance. Livestock will follow. Barley kernels are surrounded by a fibrous shell that has low digestibility. Unlike corn kernels, which are well crushed by chewing, barley grains are resistant to this action, and if whole grains are used to feed livestock, a significant amount of them will be excreted in the feces The process of adding steam to the food mixture is called condioning.In order to increase the humidity and temperature of the mesh, the food mixture is exposed to saturated vapor so that it will eventually cause starch gelatination and the activity of other bonding agents in the feed. The objectives of the study were to determine the effect of conditioning of dietary concentrate and the effect of grain type used in the concentrate and the interaction of conditioning and grain type on yield, nutrient digestibility and rumen and blood parameters of fattening lambs.

In order to investigate the effect of concentrate concentration and type of dietary grain on yield, nutrient digestibility, ruminal and blood parameters on 20 male Dalagh lambs with an average live weight of 31 ± 0.50 kg and age 4- 5 months were done in a completely randomized design with 2×2 factorial arrangement with two processing methods (with and without conditioning) and two types of grain (barley and corn). Experimental treatments include 1- Concentrate without conditioning and barley grain, 2- Concentrate with conditioning and barley grain, 3- Concentrate without conditioning and corn grain, 4- Concentrate with conditioning and corn grain. Each treatment was assigned 5 replications and in total, 20 lambs were tested for 98 days. The duration of the experiment included 14 days of habituation period and 84 days of experimental period.

There was no significant difference between treatments in the type of processing for performance (growth, daily weight gain, feed intake, feed conversion ratio) (P> 0.05). The weight of lambs receiving concentrate containing corn grain on day 56 was higher than the lambs receiving concentrate containing barley grain (P <0.05). Concentrate treatment containing corn kernels performed better than barley grain concentrate treatment in the first month as well as in the first month weight gain and first month feed conversion ratio (P <0.05). Also, in the consumption of feed in the second month, the treatment containing concentrate of corn grain had more consumption than the concentrate containing barley grain (P <0.05). There was no difference in the digestibility of dry matter, organic matter and protein between treatments. In the digestibility of ethereal extract, concentrate containing barley grain had a better performance than concentrate containing corn grain (P <0.05). No difference was observed between treatments in ammonia nitrogen concentration and pH (P> 0.05). There was no difference between treatments in blood parameters (P> 0.05). In the amount of nitrogen in blood urea, the concentrate treatment without conditioning had a higher number than the conditioning treatment (P <0.05).

The results of this experiment show that concentrate processing by conditioning numerically improves livestock performance in weight gain, feed conversion ratio, nutrient digestibility and ruminal parameters. Oh and it becomes bloody. The use of barley or corn grain in lamb fattening was not significantly different. And the use of concentrate with corn grain conditioning numerically has better performance in growth, daily weight gain, feed conversion ratio, feed intake, nutrient digestibility,

Use of antibiotics and other growth stimulants The European Union has restricted their use on farms because of the potential for antibiotic resistance in pathogenic bacteria and the impact they can have on human health. And determined the identification of alternative compounds for them in this industry. The use of additives such as herbs as antimicrobials can be a good alternative to antibiotics. Medicinal plants due to their antimicrobial properties improve the process of digestion, fermentation and production of animals. The present experiment was performed with the aim of adding Plantago major to the diet of fattening lambs on nutrient digestibility, ruminal fermentation and functional parameters.

This study was conducted in a completely randomized design with 3 treatments and 7 replications using 21 kind male lambs of approximately 4 months with an average weight of 29.11 ± 4.44 kg. The experimental diet was adjusted based on the nutritional needs table. Experimental treatments included control diet and 3 and 6% dry matter diets. The lambs were randomly divided into three groups and after a 14-day acclimatization period, they were reared in solitary confinement for 90 days. To evaluate growth and fattening performance, lambs were weighed before the experiment and then every 15 days before morning feeding with 12 hours of starvation. To measure the apparent digestibility of diets, dry matter intake, feed residue and total feces of sheep were recorded daily for 7 days from the end of the experimental period. To evaluate the concentration of volatile fatty acids and ruminal ammonia nitrogen at the end of the fattening period using esophageal catheter from the rumen of each animal, 50 ml of ruminal fluid was collected and then the pH of the samples was measured by pH meter. Rumen ammonia nitrogen concentration was measured by titration with 0.1 normal sulfuric acid and ruminal volatile fatty acids were measured by gas chromatography. Rumen protozoa were counted according to the dehydration method.

The results of this study showed that the use of Plantago major plant increased growth performance factors such as daily feed intake, daily weight gain, total weight of the whole period and feed conversion ratio. Although the use of Plantago major plant had no significant effect on the apparent digestibility of dry matter, organic matter, crude protein and NDF, but it was increased numerically. On the other hand, the addition of Plantago major in the diet had a significant effect on the total and pattern of volatile fatty acids in ruminal fluid, ammonia nitrogen concentration and protozoan concentration, but showed a significant decreasing trend on ruminal pH.

In general, the effect of adding large leaves on nutrient digestibility, rumen fermentation parameters and performance of fattening lambs showed that the use of Plantago major, especially at the level of 6% in the diet of fattening lambs can improve the yield and fermentation parameters.

Consumption of colostrum in sufficient quantity to provide the energy needed by small newborn ruminants to regulate their temperature is very important.Ruminant placenta prevents the transfer of immunoglobulin from mother to fetus during pregnancy. However, various factors such as production, nutrition, breed, duration of drought, climate and health status of goats can affect the composition of colostrum. Research has shown that small intestinal enterocyte cells lose their ability to absorb immunoglobulins within 24 to 48 hours after birth.The highest efficiency of immunoglobulin G uptake in the small intestine is 4 hours after birth and decreases linearly six hours after birth.If the goat kids do not consume enough colostrum in the early hours after birth, the risk of mortality in the herd increases. Inadequate consumption of colostrum in lambs and goat kids in the first hours after birth leads to increased susceptibility to disease and increased mortality rate, and the volume and quality of colostrum consumed can increase the survival of goat kids. Therefore, the aim of this study was to investigate the effects of different levels of colostrum consumption on the amount of immunoglobulin intake, growth performance and skeletal characteristics of Murcia goat kids.

The present study was performed on 80 newborn goats with different weights of Murcianogranadina breed with 4 treatments in a completely randomized block. Experimental treatments included four treatments of 15, 20, 25, and 30% of the newborn goat kids body weight. In that treatment was accepted.

Due to the fact that colostrum immunoglobulin levels in Murciano Granadina breed are at the highest level compared to other dairy goat breeds in the world (such as Sunan and Alpine). In the present study, feeding alternative goats with higher colostrum levels was able to grow and develop Lead to better muscle and skeleton (P <0.05). In the present study, the best results were observed in goat kids fed with levels of 30% of body weight (P <0.05). The results of this study showed that the increasing trend of skeletal growth and development for treatments consuming high levels of colostrum had continued up to 56 days. As body height and cap width were 30 and 9 cm higher for 30% colostrum treatment compared to 15% treatment, respectively, there was also a significant difference between treatments in terms of weight parameters at 21 days of age (P <0.05). And its value was the highest for 30% colostrum treatment and the lowest for 15% colostrum treatment.

The results of this experiment showed that consumption of colostrum in the first 48 hours after birth in the amount of 30% of the initial body weight of goats, the number of colostrum every 6 meals, affects the immune status and skeletal growth of goat kids.

Reproductive efficiency is one of the most important factors influencing dairy cow performance. In the present study, relationship between the polymorphism in interleukin 2 (IL-2: exon 6) and interleukin 10 (IL-10: exon 5) genes with reproductive characteristics including days open, calving interval, days from calving to first duty, gestation period, Service result, stillbirth and calving ease was examined.

In the present study, the relationship between interleukin 2 and interleukin-10 as two candidate genes with some important reproductive traits in Holstein dairy cows was investigated by means of selective genotyping. Individuals were selected based on their open door residuals obtained from mixed models. In the model used, the effects of year of birth, year of calving, time of calving and lactation were taken into account as fixed effects, and the random effects of the animal and the covariate effect of milk yield were also included in the model. A total of 194 cows, 97 of which were individual cows, were selected from both tails of the residual value distribution. The DNA was extracted using a modified salting out procedure. Polymerase chain reactions (PCR) using specific primers were implemented to amplify fragments of 172 bp and 325 bp of IL-2 and IL-10, respectively. Different banding patterns were identified using the PCR-SSCP technique. The Cox test in SAS was used to examine the association between banding patterns with open days, calving interval, days from calving to first service, gestation duration. The logistics regression was implemented in SAS for service results, stillbirths and calving ease.

The results showed the existence of polymorphism for both loci studied. Four different band patterns in IL-2 and seven different band patterns in IL-10 were observed. At the IL-10 locus, striped patterns 5 and 6 had the highest frequency and pattern 3 showed the lower frequency in the individuals with residual values below the mean. In the second group with residual values above the mean, the highest frequency was observed for pattern 6, which also had the highest frequency in the total samples. For IL-2, patterns 1 and 2 showed the greatest and lesser frequency, respectively, in the individuals with residual values below the mean. Pattern 4 had the lower frequency in this locus. Statistical results showed the significant association of IL-2 on open days and length of gestation. In addition, IL-10 had the significant effect on open days.

Taking into account the polymorphisms in the studied regions for the population of Holstein dairy cows and the association of these polymorphisms with reproductive traits, following confirmation of the results using sequencing approach, these regions could be considered in animal breeding programs.