علی داد بوستانی

So far, changes in the vaginal microbial population during the estrous cycle have been evaluated in several livestock species such as sheep. However, changes in the rumen microbial population have not been investigated during the estrous period in sheep. In a study, the results showed that the differences in the rumen microbial population in two reproductive seasons were due to the differences caused by the reaction to day length, and nutrition did not have much effect on it. It is possible that during the reproductive and non-reproductive seasons, the animal has a different microbial population in the digestive tract. The available evidence from clinical research in animals shows that microbes in the digestive system can alter brain activity and behavior through hormonal and neural pathways. Therefore, this study mainly aims to investigate changes in the rumen microbial population during the reproductive season in the estrous period in ewes with estrus and those without estrus for any reason or are so-called anestrus. The changes in the rumen microbial population during the breeding season in the estrous period were measured for the animals showing the occurrence of estrus and those not showing this trait or were anestrous.

This research was done at the same time as the non-breeding season (late spring-beginning of July). The ewes were of Grey Shirazi breed (2-3 years old). To investigate changes in the rumen fluid microbial population in the estrus cycle in estrus and non-estrus animals, two groups of 10 animals were formed from estrus and anestrus animals with the use of teaser rams, and rumen fluid samples were collected for microbial culture and other investigations in both groups once per four days (5 times) during 17 days (like estrus cycle days). The colonies were cultured and separated using general culture media with different growth factors for anaerobic bacteria colonies, such as plate count agar, MRS agar (de Man-Rogosa - Sharpe), and starch agar. The colonies were subtracted by subtractive cultures or different diagnostic tests to identify colonies. Data were analyzed using SAS software version 1/9. Means were compared with the least square procedure and adjusted for Tukey's test.

The population difference between the two groups at 5 different times showed that the population of lactic acid bacteria (LAB) on the day of estrus showed a higher value and a significant difference with other times than the anestrus group. Lipolytic bacteria were higher on the day of estrus than on all days in both groups, with a significant difference. The comparison of different groups showed that the estrous group from times 1 to 5 in the breeding season had the highest number compared to the other groups at different times of the study (p < 0.05). Anestrous groups also had the lowest number at all times (p < 0.05). The comparison of the two estrus and anestrus groups showed that heat and ninth days had higher values than the other times. In comparing the average number of lipolytic colonies in the estrus group, the highest and the lowest numbers belonged to the 1st and the 4th times, respectively, which were significantly different from the other times (p < 0.05). The population of proteolytic bacteria had the highest number of bacteria at time 1 and showed the next values at times 2, 5, 3, and 4, respectively, compared to the estrus group at time 5 (p < 0.05). Time 5 was not significantly different from times 2 and 3 (p < 0.05). In this season, the estrus group was the highest and the lowest at times 1 and 4, respectively (p < 0.05). Times 3-5 were no different significantly (p < 0.05). In the anestrus group, times 3 and 1 had the highest number vs. the lowest numbers in times 2 and 5  (p < 0.05). Based on the comparison of the average population resulting from the counting of total bacterial colonies in the examination of different groups, the estrous group had the highest number of the average microbial population in all 5 times (p < 0.05). The lowest number belonged to two anestrus groups (p < 0.05). The population difference between the two groups at 5 different times showed that the population of LAB had a higher value only on the day of estrus, with a significant difference compared to the anestrous group. The population of lipolytic bacteria in two groups of estrus and anestrus in the 5 studied times showed that the estrus group had a higher and significant value than the anestrus group in the 4th time, i.e. the day of estrus and days 5, 6, and 17. The results showed that the total bacterial population was higher in the estrus group at all times, with a significant difference. Furthermore, anaerobic bacteria increased significantly in certain days of estrus (days 1-9) compared to the anestrous group. The population difference between the two groups at 5 different times indicated that the population of LAB had a higher value only on the day of estrus, with a significant difference compared to the anestrous group. The population of lipolytic bacteria in the two estrus and anestrus groups in the 5 studied times revealed that the estrus group had a higher and significant value than the anestrus group in 4 times, i.e. days of estrus, 5, 6, and 17. The total bacterial population in the estrous group was higher and significant at all times.

In general, the colony population of amylolytic and lipolytic bacteria and the total colonies of anaerobic bacteria are significantly different on days of the estrus cycle, which may affect reproduction. Accordingly, it is better to provide more understandable results of rumen microbial effects on estrus in ewes by increasing analyses such as hormonal changes and molecular investigations, along with microbial culture in estrus crops.

Antibiotics have been used for many years in animal production to treat infectious diseases and as growth promoters. However, the misuse of antibiotics causes problems such as bacterial antibiotic resistance. Also, the possible accumulation of antibiotic residues in livestock products is risky for consumers. After the ban on the use of antibiotic growth promoters in 2006, there was a need to use substitutes in animal feed to replace antibiotics. These alternatives include prebiotics, probiotics, phytobiotics and synbiotics. Probiotics are live microorganisms that, when consumed in sufficient amounts, have beneficial effects on the host by creating a microbial balance in the gut. The purpose of probiotics is to create a competition between the species that are naturally present in the intestinal flora of broilers. The most important advantage of probiotics is that they do not remain in animal products. Prebiotics are feed compounds that are not digested by the host when consumed but can support beneficial bacteria. These compounds are short-chain carbohydrates such as non-digestible oligosaccharides that cannot be digested by animal enzymes. Compounds containing prebiotics and probiotics used in nutrition are called synbiotics. Phytobiotics include a wide range of plant-derived products with bioactive compounds. Plant feed additives (PFAs) are widely effective in improving gut health, increasing digestibility and thus growth performance. These bioactive compounds include secondary metabolites (phenolic and flavonoid). In recent years, various marine organisms have been considered as valuable biological compounds for livestock. Marine algae, due to a wide range of bioactive components such as flavonoid, carotenoid, phenolic compounds, tocopherol, peptide and various sulfated and carboxylated polysaccharides such as alginate and fucoidan with antibacterial, antifungal and antiviruses have beneficial effects on health. Brown macroalgae such as Sargassum angustifolium have beneficial effects on health due to a wide range of bioactive components such as fucoidan, fucose sulfate and polysaccharides. Also, this group of algae is a rich source of sodium alginate oligosaccharides.

The present study was conducted in the form of a completely randomized design, lasted for 42 days at the Ali Abad Kamin research farm of the Fars Agricultural and Natural Resources Research and Education Center, Shiraz, Iran. A total of 240 Ross 308 broilers were distributed in five treatments, four replications and 12 birds per replication. The dietary treatments included: 1 basal diet, without additives, 2 basal diet + 0.05% Oxytetracycline, 3 basal diet + 0.2% brown algae Sargassum and treatments 4 and 5 the basal diet was + 1% and 1.5% of synbiotics Limax, respectively. Ingredients and chemical composition of the ration are presented in (Table 1). At the end of each period, chickens in each group were weighed and the average body weight gain (g/b) in each period was calculated. Feed intake in each period was calculated and expressed as g/b/d. Based on weight gain and feed intake in each period, the FCR values of each group were calculated. Tow representative chickens from each group were selected for carcass analysis representing the average weight and variability of each group. The data obtained on various parameters studied during this experimental trial were analyzed statistically with SAS software.

The results showed that the treatments had no significant effect on the feed conversion ratio of the birds. In the finisher period (25-42 days) and total period (1-42 days), oxytetracycline and Limax 1% treatments had the highest and lowest average daily weight gain, respectively. There wasn't any significant difference between average daily weight gain of the oxytetracycline treatment and other experimental treatments. In the finisher period, the highest amount of feed intake was for the control treatment and the lowest for the Limax 1% treatment (P<0.05). The highest value of production index was belonged to oxytetracycline and Limax treatments was 1.5% (295 and 272, respectively). The highest abdominal fat percentage in the day 42 was related to Oxytetracycline treatment and the lowest was related to Limax treatment of 1.5% (P<0.05). The highest villus width in the day 42 was belonged to Limax treatment of 1 and 1.5% and the lowest was belonged to Oxytetracycline, control and Sargassum treatments (P<0.05). The treatments did not show a significant difference in the feed conversion ratio. The highest value of production index was observed in oxytetracycline and Limex 1.5% treatments (295.25 and 271.71, respectively).

The final result is that the two oxytetracycline and 1.5% of synbiotics Limax treatments shown the highest average daily weight gain and the production index among the experimental treatments. Also, the maximum width of villi and its absorption surface of villus was related to Limax treatment of 1.5%. Therefore, despite the problems of using antibiotics in the diet of birds, Limax synbiotic supplement can be a suitable substitute for oxytetracycline antibiotic.

In this research, effects of water sprayed over the upper layer of the mowed and rowed alfalfa (before baling) on quantitative and qualitative losses of alfalfa during baling process were evaluated. The study was conducted in the form of split plot experiment with 12 treatments and three replications from 2020 to 2022. Main plots were the amount of water sprayed on the alfalfa with four levels of water (0, 250, 350, and 450 liters per hectare). Subplots were the time interval between spraying water on alfalfa and baling operation (0, 30, and 60 minutes after spraying water). Alfalfa losses at the baler pickup and compression chamber, during transportation, and total losses were measured. Alfalfa dry matter, crude protein, fat, organic matter, ash, acid detergent fiber, neutral detergent fiber was measured, and amount of aflatoxin were also detected after six months of storage. Results showed that spraying 450 L water per hectare decreased alfalfa losses at baler pickup and compression chamber, transportation, and total losses by 20.4, 34.3, 4.7, and 21.1% respectively, compared to the control treatment. Time interval between spraying water on alfalfa and baling time had no significant effect on alfalfa losses during baling operation and transportation. Results also indicated that spraying water on alfalfa before baling operation had no significant negative effects on alfalfa quality after six months storing and did not reduce alfalfa quality during storing time.

This study was aimed to investigate the status of energy balance during mating, pregnancy and after lambing and its relationship with reproductive outcomes in Gray Shirazi sheep. Thirty healthy Gray Shirazi ewes that were kept in industrial conditions were randomly selected. During lambing, the ewes were examined for the rate of multiplication as well as abortions and the weight of lambs at birth. Blood sampling was performed during mating, on the last two to four weeks of pregnancy, and on one to two weeks after delivery. Serum levels of insulin-like growth factor-1 (IGF-1), insulin, non-esterified fatty acids (NEFA) and beta-hydroxybutyric acid (BHBA), and progesterone were assessed. There was a significant rise in IGF-1 level in late pregnancy compared to that in early lactation. In addition, the concentration of BHBA was significantly increased during pregnancy and postpartum compared to the mating time. Maximum BHBA and NEFA concentrations at the end of pregnancy and postpartum were in twin and singleton pregnancies, respectively. In addition, the highest BHBA concentrations were accompanied by the lowest BCS of ewes. Moreover, there was a significant direct correlation between lamb weight and NEFA, BHBA, and progesterone. In conclusion, serum indicators of energy balance, particularly insulin and BHBA, are largely influenced by reproductive stages, especially pregnancy and the number of lambs in Gray Shirazi ewes. Accurate identification of these changes is essential in diagnosing abnormal conditions and metabolic and nutritional disorders in this breed.

In this study, the effect of probiotic supplements (Protexin® (PR) and Multi Behsil® (MB)) and oxytetracycline antibiotic was evaluated on performance, egg and carcass quality, immune response and acidity of the small intestine contents of laying Japanese quails from 7 to 13 weeks of age. A total of 240 laying Japanese quails were used in a completely randomized design with 6 treatments, 4 replications and 10 birds in each replication. The experimental treatments included 1- basal diet without additive (negative control; NC), 2- basal diet+ 50 mg/kg Oxytetracycline (positive control; PC), 3 and 4 were basal diet+ 50 and 100 mg/kg of MB probiotic, and treatments 5 and 6 were basal diet+ 50 and 100 mg/kg PR probiotic, respectively. The results showed that the diets containing MB and PR probiotics improved feed conversion ratio (2.96 and 2.77 vs. 3.05), feed intake (29.49 and 29.13 vs. 30.56 gr) and egg mass (10.47 and 10.66 vs. 10.37 gr), respectively in comparison to NC treatment (P<0.05). The utilization of PR probiotics decreased the feed cost per each kilogram of egg when compared with NC treatment (P<0.05). The treatment containing 100 mg/kg PR probiotic had the maximum shell thickness (P<0.05). The utilization of probiotic had no significant effect on immune response and pH of small intestine and cecum contents of laying quails (P>0.05). Generally, the use of probiotic in the diet of laying quails was able to show the ability to compete with Oxytetracycline growth promoter antibiotic by improving performance and egg qualitative traits.

This experiment was aimed to study the effect of bacterial inoculant on some in vitro fermentation parameters and quality characteristics of barley silage. Prosage bacterial inoculant (a mixture of Lactobacillus buchneri, Lactobacillus plantarum, Enterococcus faecium and Propionibacterium acidophilus) was added at three (0, 5, and 10 mg/kg of silage dry matter) levels to barley silages. Silage quality traits including dry matter (DM), pH and buffering capacity were measured and fleig point was calculated. In vitro gas production potential, gas production rate and lag time were measured. Furthermore, total protozoa population and N-ammonia concentration of experimental silages were measured and metabolizable energy, short chain fatty acids and organic matter digestibility were estimated. Results showed that buffering capacity, fleig point and pH of experimental silages were not affected by bacterial inoculant (P>0.05), however, barley silage containing 5 mg bacterial inoculant had greater dry matter content (30.24 vs 28.07 and 28.67 %, P<0.05) compared with the control and silage containing 10 mg of bacterial inoculant. Furthermore, bacterial additive had no effect on gas production parameters and total protozoa population, N-ammonia concentration, estimated metabolizable energy, short chain fatty acids and in vitro organic matter digestibility (P>0.05). Based on the current experiment, use of bacterial additive for the preparation of barley silage is not recommended due to its costs.

The aim of this study was to investigate the effect of physical form of the diet and the type of probiotic on performance, carcass characteristics and acidity of the small intestine and cecum contents of broilers (from 1 to 42 days of age). Seven hundred and twenty day old Ross broilers were randomly distributed to 24 experimental units and 6 dietary treatments (4 replicates with 30 birds in each). The completely randomized design with factorial arrangement 2×3 with two forms of feed (mash and pellet) and three modes of using probiotic (without probiotic, probiotics Protoxin and Multi Behsil) were used. The results showed that pelleting diets resulted in greater feed intake (FI), weight gain (WG) and improved feed conversion ratio (FCR) during starter, grower and overall period (p < 0.01). The use of Protexin compared to the absence of probiotics resulted in a significant increase in WG (56.31 vs. 53.78 g/bird/day) and improved FCR (1.61 vs. 1.73) (p < 0.05). The use of probiotic supplementation in the diet caused a significant increase in the breast percentage (22.62 and 21.5 vs. 20.63) and decrease in the pH of duodenum (5.57 and 5.59 vs. 5.83), jejunum (5.95 and 5.92 vs. 6.16) and ileum (6.58 and 6.91 vs. 6.98), respectively (p < 0.05). Based on the results of this study, it can be concluded that the use of probiotic in pellet diets has led to improved breeding performance of broiler chickens compared to mash form diet. In this regard, Protexin compared to the Multi Behsil probiotic showed higher efficacy.

This experiment was aimed to study the effect of multi enzyme and bacterial inoculant on chemical composition and fermentation parameters of barley silage. Robovio multi enzyme was added at three levels, 0, 500 and 1000 mg/kg of barley dry matter (DM) and Prosage bacterial inoculant (a mixture of Lactobacillus buchneri,Lactobacillus plantarum, Enterococcus faecium and Propionibacterium acidophilus) was added at three levels, 0, 5 and 10 mg/kg of silage DM. Chemical composition, in vitro gas production, protozoa population and protein fractions of experimental silages were measured. Results showed that multi enzyme addition decreased NDF (P<0.05), pH, ash, B2 and C fractions (P<0.01) and increased A and B3 fractions (P<0.01) compared to the control. Barley silage containing 5 mg bacterial inoculant had greater DM, pH and B2 fraction (P<0.01) and lower C fraction compared to the control and silage containing 10 mg of bacterial inoculant. Protozoa population, N-ammonia concentration, estimated metabolizable energy, short chain fatty acids and in vitro organic matter digestibility were not affected (P>0.05).  Based on these results use of bacterial and multi enzyme additives for the preparation of wilted barley silage is not recommended due to their costs.

A trial was conducted to investigate the effects of dietary Coriander seed (CS) and α-tocopheryl acetate on growth performance, small intestinal morphology and nutrient digestibility in broiler chickens from 1 to 42 days of age .Two hundred forty one-old day chicks (Cobb 500) were randomly assigned to four treatments arranged in a completely randomized design with three replicates and 20 chicks per replicate. Dietary treatments included a negative control (NC) (maize-soybean diet without food additive), positive control (PC) (basal diet with 250 mg of α-tocopheryl acetate/kg), the third and fourth experimental groups basal diet were supplemented with 0.3 or 0.6 percent of CS/kg. According to the results, chickens were fed CS in comparison with control groups has not significant differences in average daily gain, feed intake and FCR. Crypt depth and surface area in absorptive villi segment in chicken fed with 0.6% CS significantly increased compared to NC group (0.22±0.011 and 0.66±0.009 versus 0.21±0.004 and 0.60±0.012 mm and mm2, respectively). Dietary supplementation of 0.6% CS significantly increased the digestibility of protein (3.99%) and fat (4.33%) compared to NC treatment. In conclusion, using of CS at the level of 0.6% in the diet of broiler chickens could be advisable due to its positive effects on dietary fat digestibility, growth performance and small intestinal morphology.