JOURNAL OF RUMINANT RESEARCH
Year:2018 | Volume:6 | Issue:3 |Papers Count:8

Background and objectives: In dairy cattle industry, there is a great interest in pre-selecting sex of offspring. Use of sex-sorted sperm is instrumental method for production of female offspring. This reproductive technique could result in more genetic progress and more economic profitability. On the other hand, the use of sex-sorted sperm in multiple ovulation and embryo transfer (MOET) programs is considered because of its potential for producing more female progeny from superior dams. The aim of this study was to investigate the effect of using sexed semen in MOET program on the genetic gain in Holstein dairy cattle. Materials and methods: True breeding values and estimated breeding values of a herd with 30, 000 heifers, 24, 900 cows in parity 1 and 19, 671 cows in parity 2 were simulated in Visual Basic 6. The traditional evaluation and genomic evaluation methods were considered for genetic evaluation. Four strategies were assumed. In the first strategy, 750 heifers were considered as donors and sexed semen was used to inseminate these donors. In the second strategy, 750 superior heifers, 622 superior cows in parity 1 and 492 superior cows in parity 2 were donors and conventional semen was used to inseminate these donors. In the third strategy, number of donors was the same as those described for strategy 2 but in this strategy, conventional semen was used to inseminate all donors. In strategy 4, sexed semen was considered for insemination of heifer donors and conventional semen was used for other donors. Results: The genetic gain of strategy 4 was more than other strategies. For example, using traditional evaluation, genetic gain of strategies 1 to 4 in new-born calves were 51. 7, 75. 6, 102. 4 and 110. 5 Kg per year, respectively. Using sexed semen for insemination of heifer donors had positive effect on genetic gain, but when cows in parity 1 and 2 were donors, using conventional semen had more potential to increase the genetic gain. Results also showed that the improved genetic gain obtained from reproductive techniques was lower than the genetic gain of sire selection in dairy herds. Conclusion: In conclusion, use of sexed sorted semen in combination with MOET for donor heifers improved the genetic gain of the herd but for donor cows in the first and second parities using sexed semen was not profitable.

Background and Object: Calpastatin (CAST) is one of the enzymes of Calpine proteolytic system. The proteolytic protein complex contains Ca+2 dependent proteases which contributes in construction, degradation and muscle tissue compression after slaughter, and is also regarded a candidate gene associated with growth efficacy and quality of meat. Materials and Methods: In this study, gene and protein coding sequences region of CAST in six mammalian species (human, rat, cattle, yak, sheep and goat) were examined. Gene and protein sequences were retrieved from gene bank and then analyzed. Homology analysis and alignment, phylogenetic and nucleotide diversity and variation in coding region and stop codon were carried out using the Clustal Ω and Mega7 softwares. SOPMA and Protparam programs were used for homology and alignment analyses, and to investigate the atoms diversity in protein structure, amino acid and terminal amino acid diversity in sequences retrieved from the NCBI database. Preferred codon sequences were obtained using CodonW software to explore the codon usage locus. Results: Codon adaptation index (CAI) had the highest value for yak (0. 256) and lowest value for sheep (0. 236). Analysis by bioinformatic software for better understanding of protein structure of CAST showed that, in all sequences, lysine amino acid was the most frequent by 623 observations and tryptophan was the least with 5 repeats in the structure of the protein. The ration of Polar amino acids to non-polar amino acids in the protein was 2. The relative efficiency of synonymous codons (RSCU) for the amino acids serine and aspartic acid as the terminal amino acid in different species were, respectively, (AGC =1/38) and (GAU =1/01). Ovisaries species showed the maximum PI and Capra hircus species had the highest value of effective number of codons index (ENC). Conclusion: hydrophobic amino acids constitute the main part of the amino acid sequence of Calpastatin protein. Given the role of inhibition of Calpastatin protein for the activity of the enzyme Calpain in muscle and considering that the most sequences of Calpain are captured by hydrophilic amino acids, the explore of amino acid sequence in Calpastatin and the role of these hydrophobic amino acids against the hydrophilic amino acids in Calpain is important. Calpastatin protein is much more tolerant in humans than ruminants. The codon bias analysis of the studied species showed that, in the evolution, Bos grunniens protein species had higher phenotype appearance for preferred codons than other species and function of the optimal codons were shown to be stronger than others.

Background: During the last few decades, there has been an increase in the development of mathematical models, as both research tools and management tools that can integrate our current knowledge of reproductive events and then would be helpful in predicting the reproductive efficiency of farm animals. This paper presents a conceptualized mathematical modeling of hormonal and metabolites interactions over non-estrous and negative energy balance phase in dairy cow. Anestrus occurs annually and after each calving. The anestrus period in high milk-producing cows due to the negative balance of energy produced by high milk production in the first few days after parturition is a constant challenge in the modern world of dairy cow worldwide. For this reason, many scientific efforts have been made to explore the biological aspects of this phase. Due to the complexity of the existing relationships between effective parameters, descriptive-analytical biological analyses have not succeeded in elucidating this biological system. In this research, it was attempted to look at the elaborating factors playing in this phase, at same time, it was tried to pinpoint and explore this phase from biological system perspective. Material and Methods: In the present study, first diverse information on the various aspects of the factors affecting on the postpartum negative balance of energy and reproduction performance of dairy cows were initially collected. Then, this information was converted to their sound mathematical equations. Efforts have been made to simplify the long and unprocessed equations from well-known factors including liver glucose, blood glucose, pancreatic insulin and blood insulin, IGF-1 liver and blood, and hypothalamic GnRH affecting on this biological phase to be simplified using ordinary differential equations. Findings: By using the data published in the scientific articles and expanding them by using Curve Expert software, the computer simulation process was performed by MATLAB software (Version 9. 1) and the predictive models were developed for some system parameters. Conclusion: The results showed that the system of ordinary differential equations was able to predict good blood glucose (AARD = 0. 388) and insulin (AARD% = 0. 638), but they were not able to provide accurate predictions for pancreatic insulin and blood IGF-1. The present model was a starting point to reach a comprehensive model which should be completed gradually. In this model, it was tried to use empirical data from reliable sources in simulation model, a matter that was more or less successful in this research.

Background and objectives: A large part of animal performance is under effect of the dietary nutrient level and the balance of nutrients in the feed consumes a great deal on the yield of the farm animals. Studies on ruminant’ s nutrition have shown that diets containing high levels of concentrate can increase the growth rate and increase the production level. Also it has been reported that high energy diets have improved the feed conversion rate. Despite its importance there is no much information about response of Iranian sheep, especially fatty tailed breeds to nutrient requirements estimated by new nutritional systems. Therefore, the aim of this study was to investigate the effect of two dietary treatments with energy level recommended by SNRS (2. 25 ME cal/Kg) and 10% higher (2. 5 ME cal/Kg) on growth performance and blood parameters of two Iranian breed lambs. Materials and methods: This study, was conducted in completely randomized blocks design with two treatments (two level of dietary energy) and two blocks (Zel and Afshari breeds) using 20 lambs with a mean body weight of 20 and 28 kg, respectively, in a 150 day period, during which time feed intake and the feed residues were weighed at the beginning and the end of each day, and each 14 days, lambs were regularly weighed. In order to investigation of the blood parameters, blood samples were collected from the venous veins of the lambs four times (on days 10, 30, 50 and 70). Finally, the parameters of triglyceride, cholesterol, HDL, and LDL were measured. Statistical analyzes were performed using SAS version 9. 2. Results: Lambs receiving high energy diet showed more weight gain. According to the results, Zell and Afshari breeds in this treatment had 24 and 34 grams, respectively, more weight gain than the low energy treatment, which was statistically significant in Afshari lambs. Also, the feed conversion ratio of lams receiving high energy diet were 0. 7 and 0. 9 units lower respectively. The results of the analysis of blood parameters showed that increase in dietary energy in Afshari lambs, increased blood glucose and triglyceride levels, and the cholesterol, LDL and HDL levels were decreased significantly with decreasing dietary energy level in both breeds. Conclusion: Based on the results of this study, it can be said that using the energy level higher than the recommendations for Afshari lambs resultsed in improvement of feed conversion ratio, which is associated with an increase in the weight gain, hence, can improve the income earned by the farmer.

Background and objective: Selenium is a trace element in feeding animals. Selenium is an essential component of thyroid hormones metabolism and plays an important role in the formation and activity of antioxidant enzyme glutathione peroxidase. Although selenium deficiency occurs in all animal species, ruminants, and especially small ruminants, such as sheep and goat, are more susceptible to this disease, which is associated with damage to myocardial infections in lambs and kids, and muscle lesion in younger ones. In the absence of selenium, it affects skeletal muscle and liver tissue, which results in increased creatine phosphokinase activity and amino-aspartate transferase in tissue and plasma. Therefore, the aim of this study was to investigate the effect of different levels of selenium supplementation on the performance and blood of feedlot kids. Material and methods: This trial was conducted to evaluate the effects of different level of selenium supplements on growth performance, hematological and plasma parameters in feedlot kids for 60 days. The experiment consisted of 18 kids, 4-5 months of age and 22. 52± 5. 02 kg average in weight randomly allotted to three treatments. Treatments were: 1) Control diet (diet without selenium supplementation); 2) Control diet + 0. 15 mg/kg Se as sodium selenite and 3) Control diet + 0. 30 mg/kg Se as sodium selenite. Kids were weighted in the beginning and on days 15, 30, 45 and 60 and daily feed intake for each animal was measured. Blood samples were collected on days 30 and 60 and plasma concentration of calcium, phosphorus, zinc, copper and iron, aspartate amino transferase, alkaline phosphatase, alanin amino transferase, creatine phosphokinase activities, serum triiodothyronine, tetraiodothyronine levels and blood glutathion peroxidase activity were measured. Results: According to obtained results, average daily feed intake and body weight were not significantly different between treatments (P>0. 05), but average daily gain in 0. 30 mg/kg group was significantly increased in comparison to control group. Feed conversion ratio was improved in selenium groups (P<0. 05). Serum concentrations of aspartate amino transferase, alkaline phosphatase, alanin amino transferase and creatine phosphokinase activities, plasma concentrations of calcium, phosphorus, zinc, copper and iron were not significantly different among groups (P>0. 05). Concentrations of triiodothyronine and glutathion peroxidase activity were significantly increased and concentration of tetraiodothyronine and triiodothyronine/tetraiodothyronine ratio decreased in selenium supplemented groups (P<0. 05). Conclusion: In conclusion, supplementation of 0. 15 and 0. 30 mg/kg selenium resulted in increased average daily gain and improved feed conversion ratio, thyroid hormones metabolism and antioxidant status of feedlot kids.

Background and objective: One of the new management methods to reduce the cost of animal breeding and also reduce the environmental pollution is the use of agricultural waste in feeding ruminants. Maize bran is one of the corn substitutes, which, due to its low cost and high nutritional value, increases animal productivity. Corn bran is a fibrous part derived from corn shell that is obtained in the process of wet milling. Corn bran protein is up to 14% and is recommended for use in livestock feeding. The present study was conducted to investigate the effect of using different levels of maize bran on performance, nutrient digestibility and ruminal behavior of Dalagh ewes. Materials and methods: In order to investigate the effect of using different levels of maize bran on performance, nutrient digestibility and ruminal behavior of Dalagh ewes, 20 Dalagh ewes with age of 5-4 years and with average body weight of 36. 3 ± 3. 7 was used. This experiment was conducted in a completely randomized design with four treatments and five replications. The treatments consisted of 1-control treatment (without maize bran), 2-treatment containing 7 percent of maize bran, 3-treatment containing 14 percent of maize bran and 4-treatment containing 21 percent of maize bran. The whole period of the experiment was carried out in 35 days, consisting of 28 days of adaptation period and 7 days for sampling period. Fecal samples were collected on days 31 to 35 for five days and four animals from each treatment for determine digestibility. On the day 29 and 30, activities on rumination behavior of ewes were estimated for 24 hours. Results: Based on the results of this experiment, using maize bran at 0, 7, 14 and 21 percent in ewe’ s diet did not significantly increase daily weight gain, final weight and dry matter intake (P>0. 05). Also, there was no significant difference in the digestibility of nutrients, dry matter, organic matter, crude protein, ADF and NDF and ether extract (P>0. 05). The use of maize bran at different levels in relation to nutritional behavior and rumination activity did not have a significant effect (P>0. 05). Conclusions: This study showed that there is no significant difference between treatments receiving maize bran with different levels and control treatment in terms of performance parameters, feed intake, digestibility and behavior of ruminal feed intake. According to the results, maize bran up to 21 percent can be used in Dalagh ewes and this feed stuff replaced instead of Cereal rations.

Background and objectives: Oil seeds are commonly used in the diet of Ruminant nutrition to meet energy and protein requirements. To eliminate the anti-nutritional substances and increasing bypass protein, soybean seeds are processed, and heat is the most common way used to processing soybeans. So using bypass proteins is important, soybean processing causes rumen un-degradable protein content to be increased, that could increase protein absorption in the small intestine and improve nitrogen utilization efficiency. The main objective of this research were the estimate the effect of dietary replacement of crud, extruded and roasted fullfat soybean with soybean meal on dry matter intake, growth performance, rumen parameters, diet digestibility and feeding behaviors in Afshari male lambs. Materials and methods: Experimental diets were assigned to the 7 groups (n = 6/group) in a completely randomized design for a 74-d period (14 d for adaptation and 60 d for data collection). Experimental diets with equal ME and CP concentrations and a forage toconcentrate ratio of 30 to 70 were formulated: treatment 1: contains 15 percent of soybean meal, treatment 2: replace of 7. 5 percent soybean meal with crud full fat soybean, treatment 3: replace of all soybean meal with crud full fat soybean, treatment 4: replace of 7. 5 percent of soybean meal with extruded full fat soybean, treatment 5: replace of all soybean meal with extruded full fat soybean, treatment 6: replace of 7. 5 percent soybean meal with roasted full fat soybean, treatment 7: replace of all soybean meal with roasted full fat soybean. Results: Dry matter intakes was effected by experimental diets (P <0. 01). Using 15% roasted full fat soybean with the mean of 1. 79 kg per day showed the highest dry matter intake. The use of extruded and roasted full fat soybean significantly increased daily gain in comparison to the crud full fat soybean and soybean meal (P <0. 05). The use of extruded and roasted full fat soybean significantly reduced feed conversion ratio (P <0. 01). In vivo digestibility of crud protein, dry matter and organic matter was not affected by the dietary treatment but neutral detergent fiber was affected by the dietary treatment (P <0. 05). Feeding lambs on diets crud, extruded and roasted instead of soybean meal had no effect on volatile fatty acids and feeding behaviors. Conclusion: The use of extruded and roasted full-fat soybean with improved daily gain, in vivo digestibility and reduce feed conversion ratio, increased the fattening performance of Afshari male lamb.

Background and objective: Based on studies conducted in response to concerns about the use of antibiotics and other growth promoters, the demand for the use of natural growth stimulants in the livestock feed industry has increased in the last 5 to 10 years because, unlike antibiotics There is no tissue residue from the use of natural growth stimulants by livestock and poultry and does not produce microbial resistance. Other additives, including sodium humate, are obtained from organic matter decomposition, were raised. The present study was conducted to investigate the effect of sodium humate on the performance, rumen parameters and Blood parameters included glucose, total protein and cholesterol, and ammonia nitrogen rumors and volatile fatty acids of Holstein calves. Materials and Methods: Fourtyeight newborn Holstein calves with mean birth weight was 37± 2 were studied in four treatments in a completely randomized design for 75 days. Calves received 4 liters of milk replacer (10% of birth weight) from day 4 of birth twice a day at 8 and 16 hours. Treatments were included as1) control (milk replacer supplement without supplementation), 2) milk replacer feeding with addition of 5 grams of sodium humate, 3) milk replacer feeding with addition of 10 grams of sodium humate, and 4) milk replacer feeding by adding 15 grams of sodium humate. In addition to milk replacer, each animal had free access to water and starter. Blood samples were taken at 30, 60 and 75 days of age, as well as rumen fluid sampling in 35 and 75 days of day after 3 to 4 hours after feeding using a vacum pump for sampling from the abdominal fluid Feed intake and calves weight were measured daily and weekly respectively. Results: Feed intake, Feed conversion, apparent digestibility cofficients of nutrients, volatile fatty acid concentrations, ruminal pH and growth parameters were affected by treatments (P<0. 05). In the entire period, there was no significant difference in feed conversion among treatments. The effects of adding sodium humate to milk were different on blood and rumen parameters. Total volatile fatty acids in the group consuming 5 grams of sodium humate daily was significantly higher than other treatments (P<0. 05). The amount of ammonia nitrogen concentration was affected by treatments at the end of the period (P=0. 04). In the end of the period, the lowest amount of ammonia nitrogen was related to treatment 2 (5 gr sodium humate). The prevalence of diarrhea was 8. 33, 3, 4and 4. 66 percentage respectively. General health score for calves consuming 5 grams of sodium humate was significantly higher than other treatments. Conclusion: In this experiment, calves consuming 5 g of sodium humate of body weight gain, health status, and blood and rumen parameters were in more favorable. The consumption of 5 grams of sodium humate had positive effects on blood and rumen parameters.