a. toghdory

Minerals are a small part of the diet, but their deficiency has major consequences for the health and reproduction of animals. Iron is not only one of the most abundant elements on Earth (it is the fourth most common element in the Earth's crust), but it is also a vital component of living things and an essential nutrient for all animal species. The main source of iron for calves and other newborn ruminants is milk or milk replacer. Milk contains relatively small amounts of iron, and calves are prone to iron deficiency. In most dairy farms, iron supplements are added as an inorganic source to the diet, which can undergo oxidation and react with other substances, causing a decrease in solubility. To solve this problem, the desired elements should be added to the ration of livestock in the form of chelated supplements. Research shows that iron plays an essential role in several metabolic processes and is necessary for the synthesis of DNA, RNA, and proteins in the body. Dietary supplements with iron have increased hematology parameters and improved growth. In addition, the presence of iron in the diet is effective in increasing appetite and glucose metabolism. Based on this, this study was conducted to investigate the effect of chelated iron supplement containing organic acid and amino acid on the performance, skeletal growth indices, fecal score, and blood parameters of suckling calves.
36 newborn male calves (with an average weight of 35.1±2.7 kg) were randomly divided into three groups with 12 replicates. The treatments included the control group (basic diet without iron supplement), basic diet with chelated iron supplement containing organic acid, and basic diet with chelated iron supplement containing amino acid. The length of the trial period was 63 days. During the experiment, calves were kept in separate locations. The rations were based on the National Research Council (NRC) report which was published in 2001. The rations were provided by total mixed ration (TMR) in calves at 8 am and 4 pm and animals had free access to water. Milk feeding was also performed in the morning and evening (10% of body weight). Calves were weighed every 21 days. The amount of feed consumed and post-feed was recorded daily. Skeletal growth in the body was measured using a standard measuring device and caliper. Three days a week, the calves' feces were randomly evaluated. On the last day, three hours after the morning meal, calves were sampled from the veins and blood parameters were determined. Sampling was done using venoject tubes with and without heparin and the samples were immediately centrifuged at 3000 rpm for 10 minutes to separate the plasma and kept at -20ºC until the day of the experiment. Glucose, urea, triglyceride, cholesterol, total protein, albumin, and globulin were determined using a Pars Test automated analyzer and kit. The measurement of mineral elements in blood serum (iron, zinc, copper, calcium, and phosphorus) was done by atomic absorption device.
The results showed that calves receiving chelated iron supplements with amino acids had an increase in the final weight, total period weight, and daily weight, and a decrease in feed conversion rate compared to the control group and treatment receiving chelated iron supplements with organic acids (P<0.05). Also, there was no significant difference in terms of dry matter and milk consumption among different treatments. There was no significant difference in terms of skeletal growth indices among different treatments. Fecal score and diarrhea status improved in both treatments receiving iron supplements (P<0.05). Consumption of iron supplements by calves in both chelated forms containing organic acids and amino acids increased blood glucose and iron and decreased blood copper and phosphorus (P<0.05). However, cholesterol, triglyceride, urea, total protein, albumin, and blood globulin were not affected.
In general, according to the results of this research, the intake of chelated iron with amino acids is recommended due to the improvement in the performance of suckling calves.

During the time around parturition, animals make many metabolic adjustments to support the transition from pregnancy to lactation. Before giving birth, animals are subjected to a lot of metabolic effects, to prepare the physiological conditions of the body in the time after giving birth and during lactation. In addition, dairy cattle produce milk more than their ability to consume energy, as a result, they are in a negative energy balance at the beginning of lactation, which may reduce the longevity of the cattle in the herd and increase the rate of elimination of dairy cattle. Heat stress in late pregnancy is aggravated by energy restriction. In such conditions, the use of management and nutritional methods will reduce the problems during the transfer period and heat stress. One of the ways to optimize the productive and reproductive conditions of livestock, through improving the metabolism of nutrients and eliminating or reducing stress conditions, is to use chromium as a metabolic improver. According to scientific sources, the chromium requirement for sheep is three to five mg per day, and for dairy cows is 15 to 50 mg per day. Inorganic chromium has a bioavailability of about 0.5%. Organic chromium has more than 25% intestinal absorption, and therefore, consumption of inorganic chromium is not recommended due to its low bioavailability and toxic effects. Among the sources of organic chromium, chromium-methionine has been recognized by important global food and drug organizations as a compound with high bioavailability, impressive metabolic responses, and no toxicity complications. This experiment was conducted to investigate the effect of using different forms of chromium around calving on feed consumption, nutrient digestibility, nutritional behavior of Afshari ewes, and the performance of their lambs under the influence of heat stress.
Forty pregnant Afshari ewes were assigned to four experimental treatments with 10 replicates from 42±5 days before the expected birth in a completely randomized design. Experimental treatments include 1) a basic diet without chromium supplementation (control), 2) a basic diet containing three mg of chromium in mineral form per kg of dry matter, 3) a basic diet containing three mg of chromium in the form of chromium-methionine per kg of dry matter, and 4) a basic diet contained three mg of chromium in the form of chromium nanoparticles per kilogram of dry matter. The length of the test period was 84 days. Weighing of ewes was done at the beginning, at the time of calving, and the end of the period. The rest of the feed is weighed every day and the daily feed consumption was calculated by deducting from the provided feed. Sampling of the rumen fluid was done on the 14th day after birth. The rumen fluid was taken before feeding in the morning (zero hour), and at three and six hours after feeding by esophageal tube, then the pH amount of rumen contents was measured and recorded immediately after extraction by a mobile digital pH meter (Metrohm laboratory pH meter-691) which was calibrated at the same place. To measure rumen liquid ammonia nitrogen, samples were used three hours after morning feeding. To measure the concentration of volatile fatty acids, five mL of rumen fluid samples were prepared and 1 mL of metaphosphoric acid 25% was added to them and kept at -20ºC until the experiment. On the 10th day after birth, blood samples were taken from the jugular vein of ewes and lambs three hours after morning feeding. To measure blood metabolites including glucose, insulin, cholesterol, triglyceride, urea, creatinine, total protein, albumin, and globulin, Pars Azmoun chemical kits and auto-analyzer (Spain BT 3500) were used.
The results showed that, from the third to the sixth weeks after birth, dry matter consumption in ewes receiving chromium-methionine and chromium nanoparticles had an upward trend compared to the other two treatments (P<0.05). The addition of chromium to the diet of ewes had no significant effect on rumen pH, volatile fatty acids, and rumen ammonia nitrogen concentration. The addition of chromium supplement to the diet of ewes caused a significant decrease in the rumen protozoa population compared to the control group (P<0.05). Adding different forms of chromium to the diet of sheep caused a decrease in glucose concentration, and an increase in chromium, insulin, total protein, albumin, and serum globulin compared to the control group (P<0.05). No significant difference was observed between experimental treatments on blood cholesterol, triglyceride, urea, and creatinine concentrations. Also, different forms of chromium did not have a significant effect on the blood parameters of the born lambs.
In general, the use of chromium, especially in the form of chromium-methionine and chromium nanoparticles, is recommended during the transfer phase of sheep under the influence of heat stress.

The management of suckling calves guarantees health and performance in their productive life. The sensitivity and low immune system in newborn calves increase the odds ratio of some disorder incidence and sometimes it is associated with the death. Therefore, the use of antibiotics in suckling calves became popular. Laws prohibiting the use of antibiotics in raising domestic animals led to the use of natural alternatives with similar properties. These compounds cause positive effects on the reduction of intestinal infections, and disorders and increase the absorption of nutrients by creating intestinal microbial balance. Prebiotics have the same feature that changes the microflora population in the digestive system. It has been proven honey has prebiotic characteristics that improve the immune system in mammals. This product and its by-products are used for different goals in human feed. This prevents intestinal infection, modifies intestine microflora population, and improves health situation and lipid metabolism. Honey is a natural product that is thickened from saturated or supersaturated sugar solutions. It usually consists of 17% water, 38% fructose, 31% glucose, 10% other sugars, and a wide range of micronutrients, vitamins, minerals, and amino acids, with a pH below 4. This study was conducted to evaluate the effect of milk enrichment with natural honey on the performance, digestibility, blood parameters, and skeletal growth indices of suckling Holstein calves.
Eighteen Holstein suckling male calves with an average weight of 58±4.2 kg were used. Treatments were divided into three groups which contained zero, 2.5, and five g per day of natural honey to the milk consumed. The duration of the experiment was 30 days evaluated in a completely randomized design. Calves were kept in individual pens and fed based on NRC requirements. Starter provided to total mixed ration (TMR) form which is given at 8:00 am and 4:00 pm daily. Calves fed milk based on 10% of body weight in the morning and evening. The amount of milk consumed by calves is measured, and to calculate the milk solids, it is multiplied by a coefficient of 12.5%. Dry matter (DM) digestibility, blood samples, average daily gain, dry matter intake, stool score, and skeleton growth were evaluated during 30 d and compared treatment by the general mixed model in SAS software.
The results of this study showed that adding natural honey to milk significantly improved the feed conversion ratio and increased the final weight, average daily gain, and dry matter digestibility of the calves (P<0.05). The group of calves that consumed five g of natural honey per day had the highest final weight and average daily gain, as well as the lowest feed conversion ratio. However, the milk and starter intakes were not affected by the experimental treatments, and there was no significant difference observed between the control group and the groups that received natural honey (P<0.05). Supplementing milk with honey improved the growth rate and feed conversion ratio of the calves, likely due to the presence of enzymes and other substances in honey that aid in breaking down polysaccharides into usable energy for the animals. Blood glucose concentration decreased in the calves that received natural honey (P<0.05), but the concentrations of cholesterol, triglyceride, high-density lipoprotein, low-density lipoprotein, and very low-density lipoprotein were not significantly different among the treatments (P>0.05). The reduction in blood glucose can be attributed to the antioxidant compounds present in honey, which can reduce intestinal glucose absorption by inhibiting the digestive enzymes of alpha-amylase or delaying the emptying of stomach contents into the small intestine. The stool consistency score increased with increasing levels of natural honey in the milk, and the group that received five g of natural honey per day had the best stool score, while the control group had the lowest stool consistency score (P<0.05). However, there was no effect of treatment on the number of animals with diarrhea or the number of days involved with diarrhea (P>0.05). Natural honey is rich in antioxidants and has prebiotic properties, which promote the growth of beneficial microorganisms and decrease harmful microflora in the gut. There was no significant difference observed in skeletal growth indices between the different experimental treatments (P>0.05).
The experiment's findings indicated that incorporating natural honey (up to five g/day) into the milk given to Holstein calves can improve their performance and health, making it a recommended practice.

Since the last two months of pregnancy (late pregnancy) constitute 75% of fetal growth, enriching the mother's diet can have positive consequences on the health and overall performance of the mother and children. Manganese functions in the immune system in different ways, including its activity in antioxidant pathways, its role in phagocytic activity, and maintaining the structural integrity of epithelial barriers against infection. Manganese deficiency can lead to dysfunction of innate and acquired immune systems in different species. Manganese toxicity is rarely observed. However, the main toxic effects attributable to this element are cardiotoxicity, hepatotoxicity, as well as deposition in specific components of the basal ganglia, and alteration of dopaminergic neuroenzyme activity. Diet enrichment with organic manganese increased feed consumption and improved dry matter digestibility in lambs. It has been documented that maternal manganese status is vital for ewe’s performance and the health of their newborn lambs. But, the required level and form of dietary manganese in ruminants are not well defined. Therefore, this study aimed to assess the influence of organic manganese supplementation on the performance, digestibility, milk yield and composition of Afshari ewes in the transition period, and the health of their lambs, For the present study, 24 single pregnant ewes were selected. They were kept in separate boxes (1 × 1 m2) with a concrete floor covered with straw during the experiment. Twenty-four lambs were born in three days from the experimental ewes. Forty-two days before lambing, the ewes were fed a diet rich in organic manganese. Water was also provided freely and separately. The experimental treatments included: 1. The first group (T1) was fed with the basal diet, 2. The second group (T2) was fed the basic diet enriched with 40 mg of organic manganese per kg DM (recommended by NRC), and 3. The third group (T3) received a basal diet enriched with 80 mg of organic manganese per kg DM (twice recommended by NRC). In this study, organic manganese (amino-manganese) contains an element of manganese and methionine, which are ionically connected. The diets of ewes were balanced using the NRC software. To calculate the weight change of the ewes, they were weighed five weeks before lambing, on the day of lambing, and five weeks after lambing. Also, the lambs were weighed on the day of birth and at the time of placental discharge. Feces and feed samples were collected in the last week for five days to test the digestibility of dry matter of ewes. They were determined in neutral detergent (NDF) by the Van Suest method, and crude protein and crude ash were measured according to the official Association of Analytical Chemists (AOAC) methods. The concentrations of fat, protein, lactose, and milk solids were measured by the Milkoscan device (MilcoscanTMS50-76510). A flame atomic absorption spectrometer model (Shimadzu-AA-670) with a wavelength of 279.5 nm was used to measure the magnesium concentration of milk. The feces of the lambs were evaluated daily. Stool scores were determined based on 1. Hard and consistent, 2. Soft and loose, 3. Loose and watery, 4. Watery with some blood, and 5. Watery with blood and mucus. At the end of the experiment, the weight and average feed consumption of ewes after delivery were influenced by organic manganese supplementation and showed a significant increase (P<0.05). While before delivery, there was no significant difference between the experimental treatments regarding the weight of the ewes (P>0.05). Also, the birth weight of the lambs and the time of placental discharge were not affected by the experimental treatments (P>0.05). The addition of different levels of organic manganese in the diet of ewes did not have a significant effect on digestibility parameters (dry matter, organic matter, crude protein, NDF, ADF, and ether extract) during the transition period (P>0.05). Supplementation of organic manganese in the diet of pregnant ewes during the transition period did not affect milk production (P>0.05). However, the amount of fat and solids in milk increased in the treatments with organic manganese supplementation, and this amount was higher in the animals that received 40 mg of organic manganese per kg DM (P>0.05). Also, the concentration of manganese in milk increased in animals that received organic manganese. In the present study, stool consistency improved under the effect of organic manganese supplementation. The number of lambs suffering from diarrhea and the average number of days suffering from diarrhea decreased significantly (P<0.05) due to the consumption of organic manganese supplements by the mother during the transfer period. Manganese is a nutrient associated with health and immunity. On the other hand, there is a close relationship between the antioxidant status of the body and the health of the animal because manganese plays a role in the structure of antioxidant enzymes such as superoxide dismutase (SOD). According to the results of this study, organic manganese acts as a valuable and safe supplement that can be used to improve the ewe’s performance and the health of newborn lambs.

The objective of this study was to evaluate the effect of the replacement of different levels of wheat straw with cottonseed plant on performance, digestibility, blood parameters, and rumination behavior of Dalagh ewes. Therefore, 15 ewes with three treatments and five replications were used in a completely randomized design. The treatments consisted of 0, 50, and 100% replacement of wheat straw with cottonseed plant. The whole period of the experiment was carried out in 35 days, consisting of seven days for the adaptation period. Ewe body weight was recorded weekly. Fecal and feed samples were collected on days 31 to 35 for five consecutive days from each treatment to determine digestibility. Blood sampling was done on day 35 and 4 hours after morning feeding. On days 29 and 30, the rumination behavior of ewes was estimated for 24 hours. Results indicated that dry matter intake and weight gain in the second treatment (50% cottonseed plant) increased and feed conversion rate was decreased, but generally performance and digestibility were not affected by treatments. Also, there was no significant difference between experimental treatments in digestibility. Results of the present experiment showed, by increasing the amount of whole cottonseed plant in ewe diets, the concentration of triglyceride increased (p < /em><0.05). The most and the least concentrations of glucose were observed in the first (contained 0% cottonseed plant) and second treatment (contained 50% cottonseed plant), respectively. With the reduction of wheat straw levels in the diet, chewing time and rumination behavior were increased. The difference was not significant in eating, rumination, and chewing behavior. Based on the results of this experiment it could be possible to replace the cottonseed plant in the diet of ewes.