کاظم کریمی

A study was performed to investigate the effect of rumen protected methionine (RPM) on growth traits and feed efficiency of weaned Holstein calves using 40 calves in 4 experimental groups in a CRD plan with repeated measures were done. The experimental groups were included: 1) control (not given RPM after weaning at 75 days) 2) group was given RPM until 10 days 3) group that was given RPM until 20 days 4) group that was given RPM until 30 days after weaning. RPM was used in the amount of 2 g/d/calf. The studied traits included weight and average daily gain, body length and height, and calculated feed efficiency of experimental period. The results showed that the average feed and nutrient intake (protein and energy) of the third and fourth treatments at the ages of 85, 95 and 105 days were 9.79, 10.12 and 10.27% higher than the average of the first and second treatments (P<0.05). Daily weight gain and feed efficiency of these treatments were also 15.92% and 4.63% respectively (P<0.05).Treatments using methionine supplements had a higher average weight (4.16%) and a higher average height increase (8.15%) than the control (P<0.05). In conclusion, the use of coated methionine supplement in the ration of calves after weaning had a positive effect on growth performance, height measure and overall feed efficiency and it can be recommended at the mentioned level to the farmers. Key words: Body measures, Gain, Feed efficiency, Holstein calves.

In order to evaluate the cholesterol lowering effects of psyllium seeds and also to evaluate the effects of this medicinal plant on growth efficiency, blood parameters, carcass traits and quail egg quality, 160 21-day-old chicks were studied in cages using a 2×2 factorial design with two dietary levels of psyllium seeds (0 and 3%) and two dietary levels of cholesterol (0 and 1%) in a randomized complete block design with 16 experimental units including 4 treatments and 4 replications and 10 birds (male and female) in each replication for 40 days, which were divided into two 20-day periods (as first and second breeding periods). Experimental treatments included a diet without psyllium seed and cholesterol, a diet containing cholesterol, a diet containing psyllium seeds and a diet containing psyllium seed and cholesterol. Serum, egg yolk and muscles (thigh and breast) cholesterol were evaluated in the treatments along with growth efficiency, blood parameters and egg and carcass quality. The results showed that oral administration of cholesterol had no effects on increasing serum lipids and cholesterol (P>0.05). In quails fed diets containing psyllium seeds compared to diets without psyllium seeds, breast and thigh muscles and egg yolk cholesterol, lymphocytes, relative weight of visceral organs, cecum, testis, thigh and liver were decreased and white blood cells, neutrophils, relative weights of carcass, duodenum, breast and pancreas were increased (P<0.01). The use of psyllium seeds throughout the entire study period increased feed intake and weight gain. The feed conversion ratio improved in the first period of rearing due to the use of psyllium seeds in the birds' diets. It was found that while cholesterol is  used solely in the diet, it increases the level of cholesterol in the muscles of the breast and thighs and egg yolk compared to the control group, but while cholesterol is used in combination with psyllium seed in diet, no increase in the cholesterol of those organs will be observed. Therefore, the use of psyllium seeds in diets with high cholesterol levels can play a beneficial role in preventing the increase of muscle and yolk cholesterol.

This study, was conducted in one of the rangeland of Lar National Park, Estarkolak and Malek Cheshmeh area (3176 hectares) to estimate the amount of metabolizable energy and daily requirement of animal. In this research, to determine the weight of various classes of Zandi sheep grazing in the Lar National Park rangelands of Estarkolak and Malek Cheshmeh region, three prevalent flocks of Zandi race were selected randomly and from each flock, 60 heads of animals including 20 heads of ewe ageing 3 years old, 20 heads of ewe aging 4 years old, 5 heads of ram aging 3 years old, 5 heads of ram aging 4 years old and 10 heads of lamb aging 3 months were signed and selected in two phases, one at the beginning of the season and the other at the end of season. In the study area, first a topographic map with a scale of 1: 25000 was prepared and the location of the plots was randomly determined on the map and then the rangeland. Inside each plot, all grazable animal plants were identified and according to the size and height, one centimeter of soil surface was harvested. The forage species grazed by sheep at the flowering stage were identified and collected in this rangeland (41 plant species). Having utilized the mean weight of ewes aging 3 and 4 years, the weight of the sheep glazing in the studied region was estimated to be equal to 48.54 ±2.44 kg. The forage species grazed by sheep at the flowering stage were identified and collected in this rangeland. The mean percentage of CP, ADF, DMD and the amount of ME in every kg of dry forage were determined 12.8, 37.54, 57.74 and 7.81 mega joule, respectively. Metabolizable energy and animal daily requirement based on dry matter in maintenance condition for animal unit equivalent of this rangeland were estimated 10.29 mega joule and 1.31 kg respectively. Using the results of this study, new grazing capacity can be determined for this rangeland.

A total of 500 one-day old broiler chicks (as hatched) were assigned to 4 treatments with 5 replicates and 25 chickens in each replicate. Experimental design was a completely randomized block design in a 2×2 factorial arrangements with 2 levels of citric acid (0 and 0.4 % of diet; A0 and A1, respectively) and 2 levels of phytase (0 and 2000 FTU/kg diet; P0 and P1, respectively) in three phases including starter (1-10d), grower (11-24d) and finisher (25-42d). During grower, finisher and overall period of experiment feed intake and body weight gain was increased by dietary citric acid addition. Dietary phytase supplementation increased feed intake at finisher and overall period of experiment (P>0.05) and increased body weight gain during grower and overall period of experiment (P>0.05). The interaction effect of phytase and citric acid was significant for feed intake and body weight gain through the experimental period (P<0.01). Serum phosphorous was increased by phytase supplementation and alkaline phosphatase decreased by inclusion of citric acid to the diet (P>0.05). The interaction effect of phytase and citric acid significantly increased serum calcium, alkalin phosphatase and phosphorous in A0P0, A1P0 and A1P1 treatments, respectively (P>0.05). Crypt depth and villi length were significantly higher in A1P1 and A1P0 treatments, respectively (P<0.05). it was concluded that dietary addition of phytase improves broiler performance and intestinal morphology and the effect was more pronounced by supplementation of citric acid.

Being aware of the animals` food requirement, the amount of available forage in the rangeland and forage quality is necessary as the first step in successful management of animals and rangeland. in this study, Animal unit weight equivalent, maintenance metabolizable energy and daily requirement of grazing sheep were studied. Therefore, determining the weight of various animals` classes grazing in the rangeland and their conversion factor regarding country`s animal unit is an essential issue. In this research, to determine the weight of various classes of Zandi sheep grazing in the Lar National Park rangelands of Siah Palas region in position 35 degrees and 54 minutes north latitude and 32 degrees and 52 minutes east longitude, three prevalent flocks of Zandi race  were selected randomly and from each flock, 60 heads of animals including 20 heads of ewe ageing 3 years old, 20 heads of ewe aging 4 years old, 5 heads of ram aging 3 years old, 5 heads of ram aging 4 years old and 10 heads of lamb aging 3 months were signed and selected in two phases, one at the beginning of the season and the other at the end of season. Having utilized the mean weight of ewes aging 3 and 4 years, the weight of the sheep glazing in the studied region was estimated to be equal to 1.59±49.96 kg. Various kinds of forage being glazed by the sheep were identified and collected in this rangeland at the flowering stage on 05/06/2019. The mean percentage of CP, ADF, DMD and ME in every kg of dry forage for 41 plant samples equaled to 4.77±11.18, 39.19±7.89, 56.11±7.83, 7.58±1.26 mega joule, respectively. Daily metabolizable energy for maintenance condition of animal unit equation of this rangeland  for 120 ewes, equaled to 10.54 ± 0.35 mega joule in a day and its daily need was estimated to be 1.38±0.04 kg based on the consumed dry material and considering the quality of the forage. Overall, being aware of daily food needs is necessary for the diet of animals. It should be considered in providing managerial designs.

Effect of zeolite in preparturient diet on production, and reproduction traits in a completely randomized design with repeated measurements in time was studied. Diets included: 1) Control group (without zeolite), 2) Control+0.75% Zeolite, and 3) Control+1.5% zeolite. Dietary Ca was based of NRC recommended. The diets were fed to the animals during the last 15 days of gestation. After calving, all animals were fed with the same diet and their performance was evaluated. The control group had better raw milk production, and dry matter and energy intakes, but feed efficiency was higher in zeolite-consuming cows (P≤0.01). Protein, NDF and ADF intakes and corrected milk production (4%) were not significantly different among the groups. The milk fat percentage of zeolite-consuming cows were higher than the control (P≤0.01), but the percentages of protein, lactose and SNF were not significantly different. Plasma concentrations of total Ca, Ca++ and their ratio were similar during calving, but higher in zeolite-consuming cows at 6, 12 and 24 h postpartum (P≤0.01). The frequency of hypocalcaemia and postpartum disorders were higher in the control group than the other two groups (P≤0.01). Body condition score and colostrum quality of zeolite-consuming cows were higher than the control (P≤0.01). According to the results of this research, the use of zeolite at the level of 1.5% DM of preparturient diet is recommended and compared to the level of 0.75% DM and control group, it has a better effect on controlling blood Ca concentration and improving the production and reproductive traits of cows.

Applying low-calcium to control milk fever have many problems in practice. Dietary Ca levels should be reduced by quantitative and qualitative methods such as limiting feed intake, which negatively affects the milk production and health of the cows. Anionic salts are also expensive and should be consumed before calving for a long period. It is also difficult to produce a homogeneous diet for selected cows in special section of a farm. In addition, add these salts to cows' diets reduces the palatability of the diet, decrease dry matter intake, conversely, increase negative energy balance and the concentration of non-esterified plasma fatty acids. Therefore, as an important goal of this research, it seems vital to introduce a method that solves the problems and have many advantages to improve productive traits and health related factors of fresh cows during a hot full stressed summer.

Study was performed by 60 Holstein cows near calving in 3 experimental groups using a completely randomized statistical design with repeated measurements in time. Study was done in summer season, adaptation and experimental period were 15 and 45 days from -15 to +30 after calving time, respectively. Experimental diets including: 1) Low-Ca or control diet (Ca=0.44%), 2) Anionic diet (Ca=1%), 3) Control +enriched Zeolite diet. From second week after calving the cows were fed with a fresh milking diet The DCAD of diets were +100, -100, +100 mEq/kg DM respectively. The Anionic and Zeolite supplementation were used at level of 2.8 and 1.5% based on daily DMI of cows. Experimental traits were included milk production and compositions, total and ionized plasma calcium and some reproductive disorders.

According to the results, consumption of DM and energy between diets were significantly different. Fat percentage of zeolite diet was higher than others but raw and corrected milk yield of anionic diet was the highest (P≤0.01). Plasma and ionized Ca concentration of zeolite diet were the same with two other diets at calving time but at 6, 12 and 24 hours after that were significantly higher than others (P≤0.01). The frequency of severe and subclinical hypocalcaemia was higher in control diet and older cows, but in zeolite diet was lower than others (P≤0.01). The highest BCS was for zeolite (2.98) and the lowest (2.86) for control diet (P≤0.01). The frequency of postpartum disorders (calving difficulty, retained placenta, endometritis, and abomasum displacement) was significantly lower in zeolite and anionic diets than control (P≤0.01). Highest percent of ssuccessful pregnancy, inversely, lowest percent of culled cows from herd observed in zeolits and anionic diets (P≤0.01).

According to the results, improved dry matter and energy consumption was observed in zeolite diet compared to anionic which had a direct effect on milk productive traits. Improved total and ionized Ca plasma concentrations during calving and after that and better control on hypocalcaemia and related problems in the herd, with highest BCS and a significant reduction in the frequency of postpartum disorders are of the advantages of zeolite diet. So the proposed method of calcium restriction using zeolite supplement seems to be successful and can be used as an alternative for common methods.

Being aware of the animals` food requirement, the amount of available forage in the rangeland and forage quality is necessary as the first step in successful management of animals and rangeland. Therefore, determining the weight of various animals` classes grazing in the rangeland and their conversion factor regarding country`s animal unit is an essential issue. In this research, to determine the weight of various classes of Zandi sheep grazing in the Lar National Park rangelands of Aroo region, three prevalent flocks of Zandi race were selected randomly and from each flock, 60 heads of animals including 20 heads of ewe ageing 3 years old, 20 heads of ewe aging 4 years old, 5 heads of ram aging 3 years old, 5 heads of ram aging 4 years old and 10 heads of lamb aging 3 months were signed and selected in two phases, one at the beginning of the season and the other at the end of season. Having utilized the mean weight of ewes aging 3 and 4 years, the weight of the sheep glazing in the studied region was estimated to be equal to 1.65±48.03 kg. Various kinds of forage being glazed by the sheep were identified and collected in this rangeland through two phases of flowering and seeding. The mean percentage of CP, ADF, DMD and ME in every kg of dry forage equaled to 11.56, 37.78, 56.88, 7.69 mega joule, respectively.

In order to investigate the effects of the Tarragon byproducts on the growth performance, carcass traits, cellular and humoral immunoresponse of broilers, one-day- old one hundred sixty-eight Ross 308 chicks were randomly allocated in to four treatment groups in 24cages (6 replicates per treatment) and 7 chicks per replicate. The treatments were included: 1) basal diet (control), 2) basal diet + 500 μl/lit Hydro alcoholic extract of tarragon in drinking water, 3) basal diet + 1% dietary tarragon powder and 4) basal diet + 1% dietary tarragon powder + 500 μl/lit of tarragon extract in drinking water. Results indicated that at the starter, grower, finisher and total periods of time, the birds that were recived 1% dietary tarragon powder had a better growth performance rather than other birds, so that, feed intake and weight gain were significantly increased (P ≤ 0.05) and feed conversion ratio was improved. In these birds, the relative weights of carcass and bursaof Fabresious was also greater than other birds (P ≤ 0.05). No significant differences were observed in the cellular immunity response (change in foot membrane thickness in response to Phytohemagglutinin injection) and humoral imiunity response (antibody response toNewcastle virus and antibody response to injected SRBC) due to treatments. Based on the results, the use of one percent tarragon powder in the diet of broilers is recommended to improve the growth efficiency and carcass yield.

Knowledge of the daily nutrient requirements of grazing animals in rangelands of different climates is essential to calculate grazing capacity in rangeland plans. In this regard, the daily metabolizable energy requirement at the maintenance level for small wild ruminants grazing in Lar National Park rangelands were studied. For this purpose, according to the average values of forage quality indexes of rangeland species and their contribution to rangeland vegetable composition, the among of metabolizable energy was estimated in kg of dry forage rangelands and considering the daily metabolizable energy requirement of small wild ruminants, the amount of feed provided for the daily requirement of livestock was calculated to calculate the separate grazing capacity of these animals in the rangelands of the region. Using the animal unit weight of small wild ruminants, the required daily maintenance metabolizable energy for grazing animals were determined using equation method of MAFF and NRC standard in the studied rangelands. Forage species of grazing animals were identified and collected at flowering stage in the studied rangelands. Results also showed mean of percentage 12.42±0.17, 37.59±0.28, 57.81±0.28 and 7.89±0.07 were respectively for CP, ADF, DMD and ME (MJ) per kg dry forage was estimated. Also Daily metabolizable energy was calculated for grazing wild ruminants such as: male goat, female goat, ram and ewe. The results also showed daily metabolizable energy were 16.32±1.25, 14.07±1.36, 13.67±1.15 and 11.58±1.21 MJ/day and for daily requirement 2.06±0.25, 1.78±0.12, 1.71±0.17 and 1.46±0.25, respectively for male goat, female goat, ram and ewe.  Using the results of this study, we can determine the new and separate grazing capacity for wild ruminants in the study areas. The results also showed that because of the cost of determining the quality of forage, these results can be used to estimate the daily requirement of these livestock in different years.

A total of 36 breeder roosters were divided to 4 dietary treatments which were consisting of 3 pens with 3 birds per pen. Treatments were as follow: 1) Control diet without vitamins C and vitamin E, 2) C-diet containing 1000 mg/kg vitamin C, 3) E-diet containing 1000 mg/kg vitamin E and 4) E+C diet containing vitamins C and E (1000mg/kg of each vitamin). Diets were fed to the roosters for a 28 d experimental period. Sperm collection was done by rubbing the belly method, and semen was diluted by of solution tris buffer and kept at 5°C temperature. Evaluated parameters were as follow: semen volume, sperm concentration, sperm motility, progressive sperm, live sperm, at 0, 6, 12, 24, 48, hours after sperm collection. Data analyzed by CRD and mean compared with Duncan multiple range test at the 5% level (P<0.05). Results indicated that Vitamin E resulted in  increasing of semen volume and concentration, motility, live sperm, progressive sperm, at all evaluated times. Results of vitamin E+C diet were similar to vitamin E diets but despite of vitamin E this diet (C+E) is same as vitamin C diets, too. It seems that, in this study, dietary vitamin E can improve Varaminian rooster sperm characteristic rather than the other experimental groups in dirds. Therefore addition of vitamin E in the rooster diets in order to improve sperm characteristics, can be recommended.

This study was carried out in order to evaluate the relationship between some productive and reproductive factors with calf sex (CS), in Shahryar city from 2017 to 2018. Synchronization and pregnancy detection were performed by a veterinarian. Heat detected cows were inseminated by artificial insemination (AI) or mated by bull cow based on their reproductive history. Implantation of fetus in left-side or right-side of uterine horn was determined by sonography. The CS of newborn calves was also registered immediately after calving in order to analyze the sex ratio. Results showed that the intervals between calving and first insemination service had no significant effect on CS. In addition, CS was not affected by age of cow and type of insemination. However, implantation of fetus in the rightside compared to the left-side uterine horn resulted in a greater ratio of female than the male calves(P>0.05). The ratio of female calves in the dairy cows with high milk production (45%) was higher than those with low milk production (25%, P<0.05). The primiparous cows significantly produced (P<0.05) higher ratios of female calves (60%) rather than multiparous cows (47%, 46% and 47% in the second, third and fourth parturition, respectively). It can be concluded that, the uterine horn side implantation, level of milk production and primiparous or multiparous cows’ statement are effective factors on CS. Therefore, it is possible to convey the sex ratio of new born calves to a desired ratio by manipulating some parameters in dairy cows before the birth.