اردشیر محیط

Feather biodegradation is an effective alternative to other processing methods.

This study aims to investigate the effects of hydrolyzed feather meal (HFM) on broilers’ antioxidant status, meat quality, and immune response. 

In October 2022, 480-day-old Ross 308 male broilers were used for 42 days in a completely randomized design with eight treatments and five replicates (12 chicks/replicate) in the research farm of Agriculture Faculty, Guilan University (Rasht City, Iran). The experimental diets were as follows: (1) control diet (without feather meal [FM]), (2), (3), (4), (5), (6), (7), and (8) all containing 4% raw FM (RFM), HFM by autoclave (Au-HFM), fermented FM (FFM) by Bacillus licheniformis (Bl-FFM), FFM by Bacillus subtilis (Bs-FFM), FFM by Aspergillus niger (An-FFM), FFM by B. licheniformis+B. subtilis+A. niger (Co-FFM), and HFM by an enzyme (En-HFM), respectively.

The results of the in vitro experiment showed that 2,2-diphenyl-1-picrylhydrazl (DPPH) and 2, 2ʹ-azino-bis-3-ethylbenzthiazoline-6-sulfonic acid (ABTS) radical-scavenging activities, as well as microorganism count of FFM, increased with increasing fermentation time (P≤0.05). Also, the pH of FFM significantly decreased by increasing the fermentation time (P≤0.05). The DPPH and ABTS radical-scavenging activities of FFM were higher than those of RFM, Au-HFM, and En-HFM (P≤0.05). The in vivo experiment results showed that the total antioxidant capacity (TAC) serum levels, glutathione peroxidase (GPX), superoxide dismutase (SOD), and catalase (CAT) in the FFM were higher than those in the control and other treatments (P≤0.05). Compared to control and other treatments, broilers fed FFM had lower meat malondialdehyde (MDA) levels, higher meat pH, and higher water-holding capacity at 0, 7, and 14 d of the breast meat storage, as well as lower serum MDA levels (P≤0.05). Broilers fed FFM had higher antibody titers against Newcastle disease virus, lower heterophil count, and lower heterophil-to-lymphocyte ratio, as well as higher total anti-sheep red blood cell (anti-SRBC) titer, immunoglobulin G (IgG), and immunoglobulin M (IgM), compared to the control and other treatments (P≤0.05).

Fermentation of FM increased its antioxidant properties, improved the body’s antioxidative status, and contributing to improved the meat quality and immune response of broilers.

Essential oils are volatile and concentrated liquids extracted from various parts of medicinal plants. In recent years, the use of essential oils in animal nutrition has gained interest as an alternative for antibiotic growth promoters. The main issue with using essential oils in poultry diets is the high volatility, which must be addressed by developing encapsulation techniques to preserve their efficacy. The purpose of the current experiment was to determine the effects of dietary supplementation of microencapsulated essential oil of Satureja khuzistanica on growth performance, oxidative stability of meat, and intestinal microflora of broilers.
A total of 320 1-d-old Ross 308 chicks were studied in a completely randomized design with a 2×4 factorial arrangement of treatments. The factors were two administration forms of essential oils (free and microencapsulated) and four levels of dietary supplementation (0, 50, 100, and 150 mg/kg). The experiment consisted of eight treatments, four replicates, and 10 broilers per replicate. The essential oil of Satureja khuzistanica was microencapsulated using a 2% sodium alginate solution, which was mixed and homogenized before being transferred into a funnel and dropped into a beaker containing a 5% calcium chloride solution using a needle from a syringe. The beads were gently stirred for an hour to solidify. After one hour, the beads were filtered through a sieve and washed with distilled water. The beads were thoroughly rinsed before being air dried at 23 °C for 12 hours and kept in airtight containers. Body weight and feed consumption were monitored in pens weekly. From these data, average daily gain (ADG), average daily feed intake (ADFI), and feed conversion ratio (FCR) were calculated weekly and throughout the entire rearing period. The European production efficiency factor (EEF) was also calculated for the whole rearing period. The minimum inhibitory concentration (MIC) of Satureja khuzistanica essential oil was determined by broth microdilution method for each of Escherichia coli, coliforms and lactobacillus bacteria. On day 42, two birds from each replicate were slaughtered and ileal samples were taken for microflora analysis. Total Escherichia coli, coliforms, and lactobacilli were enumerated in ileal digesta by the plate method using specific mediums. The thiobarbituric reactive substances (TBARS) assay was used to determine the oxidative lipid changes of the meat.
The in vitro results demonstrated that the MIC of savory essential oil against gram-negative Escherichia coli and coliforms was higher (0.276) than its MIC for gram-positive lactobacillus bacteria (0.069). Throughout the in vivo study, the ADFI of broilers fed the diet with 150 mg/kg of essential oil was lower than the control (103.3 vs. 108.8; P<0.05). The ADG of broilers fed 100 mg essential oil/kg of diet was more than those fed 150 mg/kg (60.1 vs. 54.2; P<0.05). Broilers fed microencapsulated essential oil in their diet had a higher (P<0.05) EEF than those fed free essential oil. The addition of savory essential oil at 100 and 150 mg/kg of diet reduced (P<0.05) the lipid peroxidation in broilers meat stored for 60 and 90 days compared to the control. Lipid peroxidation of meat was lower (P<0.05) in broilers fed microencapsulated essential oil in the diet than those fed free essential oils. The addition of savory essential oil at different levels of 50, 100, and 150 mg/kg diet reduced the count of coliforms in the ileum compared to the control (P<0.05). Moreover, the data indicated that the addition of the essential oil at 100 and 150 mg/kg diet reduced the number of Escherichia coli (P<0.05). The bacterial count of coliforms and E. coli was lower in broilers fed microencapsulated essential oil than those fed free essential oil.
The results of this study showed that supplementation of Satureja khuzistanica essential oil in the diet improved broilers' performance and intestinal microflora. Microencapsulation of savory essential oil with alginate improved broiler growth performance, EEF, and increased the antibacterial activity of the essential oil which resulted in a further decrease of pathogenic bacteria. According to the findings of this study, 100 mg of microencapsulated savory essential oil per kg of broilers’ diet can be recommended due to its beneficial effects on performance, oxidative stability of meat, and intestinal microflora.

This study aimed to investigate the effect of reducing the dietary level of crude protein (CP) and inclusion of extruded soybean meal (SBM) and canola meal (CM) on blood and ruminal parameters, the population of methanogens, and hyper-ammonia producing bacteria (HAB) of feedlot calves. To this purpose, 36 male calves were used in a completely randomized experimental design with six treatments and six replicates. Experimental treatments included: 1) Control (CP=15%, SBM (15SBM)), 2) SBM (CP=13%, 13SBM), 3) Extruded SBM (CP=13%, EXSBM), 4) CM (CP=13%, 13CM), 5) Extruded CM (CP=13%, EXCM), and 6) Fish meal (CP=13%, FM). Concentrations of albumin, total protein, creatinine, and blood urea nitrogen in experimental treatments decreased compared to 15SBM (P>0.05). The highest values of ruminal ammonia and acetate and the lowest amounts of propionate and volatile fatty acids (VFA) were observed in the 15SBM (P<0.05). The minimum ruminal HAB population was observed in EXSBM and EXCM and then in 13SBM, 13CM and FM and was maximum in 15SBM (P<0.05). Also, treatments fed EXSBM and EXCM had a smaller methanogens population than the control group (P<0.05). Based on the results obtained, decreasing dietary CP level and processing of extrusion for SBM and CM decreased HAB population, rumen ammonium, and blood urea concentration. Furthermore, extrusion declined methanogens bacteria population and acetate to propionate ratio and increased total VFA concentrations which can be considered as an indication of the rumen improvement in fermentation efficiency index.

The objective of the current research was to investigate the influence of different levels of dietary energy and stocking density on body weight and immune system response in Ross 308 broiler breeder hens. For this purpose, a completely randomized design with 9 treatments included three diet energy levels 2600, 2750 and 2900 ME/Kg and three levels of stocking density (4, 6.5 and 9 birds/m2 in rearing and 3.5, 5.5 and 7.5 birds/m2 in laying period), were used with factorial arrange (3×3) and 4 replicates The results showed that, with increasing dietary energy level, live weight of hens increased significantly from 21 weeks to the end of the experiment (P <0.05), on the other hand, high density from the beginning of the experiment until 31 weeks had no significant effect on live weight of hens, but in the last 10 weeks, higher density caused more weight gain (P<0.04). The percentage of lymphocytes, monocytes, heterophiles and the ratio of heterophiles to lymphocytes did not show a significant difference between the three energy levels. However, the percentage of heterophils, lymphocytes and the ratio of heterophils to lymphocytes were higher in the high-density treatment (P <0.05). There was also no significant difference between the treatments in the observed titers including infectious bursal disease (IBD), bronchitis (IBV), reovirus (REO), Newcastle (ND) and influenza (AI). The results showed that increasing stocking density can cause stress in the herd and if the herd stocking density increases, it is necessary to re-evaluate the energy requirement.

This study was conducted to investigate the effects of two types of omega-3 calcium fat powders with animal and vegetable origin on productive performance, reproductive and egg quality of broiler breeder hens by using 60 hens and 20 roosters (65 weeks), in a completely randomized design with five treatments and four replicates for two months. Experimental treatments were: 1- control (without fat powder); 2- 1.5% animal omega-3 calcium fat powder based on fish oil; 3- 3% animal omega-3 calcium fat powder based on fish oil; 4- 1.5% vegetable omega-3 calcium fat powder based on flaxseed oil; 5- 3% vegetable omega-3 calcium fat powder based on flaxseed oil. Egg production percentage and economic benefit of hens fed with diets containing 1.5% animal and vegetable fat powders were greater than hens that received 3% of them (p<0.05). The highest concentration of yolk docosahexaenoic acid and docosahepanthanoic acid were in eggs of hens fed with diet containing 3% animal and vegetable fat powder and thelowest concentration of linolenic acid was in the yolk of eggs obtained from control hens or hens fed with diet containing 1.5% animal fat powder (P<0.05). The lowest percentage of hatchability and the highest omega-6: omega-3 ratio were related to hens received control diet (P<0.05). Based on current results, adding animal or vegetable omega-3 calcium fat powder at the level of 1.5% in old broiler breeder hen’s diet, without negative effect on performance, improve hatchability and yolk fatty acid composition and is economically more affordable.

This study was conducted to determine the effect of different levels of omega-3 and omega-6 calcium fat powders on performance, hatchability, serum lipids, abdominal fat, and ovarian follicle count in Ross-308 broiler breeder hens (65 week-old). The experiment was performed in a repeated measurement design with 84 hens and 28 roosters with seven treatments (four replicates) during three months. The experimental groups included control group (no fat powder), 1.5 and 3% of animal omega-3 calcium fat powder of fish oil origin (ω3F), plant omega-3 calcium fat powder of linseed oil origin (ω3L), and omega-6 calcium fat powder of soybean oil origin (ω6S). The results showed that the highest average of HDEP was belonged to the experimental groups containing 1.5% ω3F (61.98), and ω3L (60.25) without significant difference with together (P> 0.05). However, among experimental groups, the highest egg mass (44.78 g/h/d) was obtained from consumption of 1.5% ω3F (P<0.05). The highest concentrations of triglycerides (1806.8 mg/dL), cholesterol (206.25 mg/dL), and low density lipoprotein (244/25 mg/dL) of serum were belonged to control group that was significantly different from other experimental groups (P<0.05). The percentage of hatchability of fertile eggs was improved by consuming diets containing fat powder, except 3% ω6S, when compared to control (P<0.05). Overall, considering the production performance, hatchability and economic explanation of diets, it seems that addition of omega-3 calcium fat powder at the level of 1.5% (ω3F and ω3L) is affordable and can have a positive effect on old broiler breeder hens.

In this experiment, a total of 360 one day-old female Ross 308 broiler chicks in a completely randomized design with a 2 × 3 factorial arrangement were allocated to 6 dietary treatments, each replicated five times with 12 birds per replicate. The included factors were two levels of green tea extract (GTE, 0 and 500 mg/kg diet) and three type of diets: 1- diet without dietary fat, 2- diet supplemented with soybean oil (SO) and 3- diet supplemented with Tallow (Ta). Use of GTE did not affect intestine microbial populations, intramuscular fat, oxidative stability of mat and performance in broiler chicken (p>0.05). Body weight gain and feed conversion ratio of chicks fed diet supplemented with SO or Ta was improved compared to the diets without fat (p<0.05). Use of SO compared to Ta and diets without fat led to higher and lower abdominal fat and carcass yield, respectively (p<0.05). GTE supplementation in diets high in fat was effective in decreasing abdominal fat percentage (p<0.05). The broilers that received green tea extract and soybean oil had a higher lactobacillus populations than those fed GTE with Ta (p<0.05). Dietary SO led to significantly greater intramuscular fat and thiobarbituric acid reactive substances (TBARS) values in thigh meat (p<0.05). Based on the findings of this study, despite the improvement in gut microbial populations and carcass fat content by GTE addition in diets high in un/saturated fats, its effect on intramuscular fat contents and muscle antioxidant capacity was not significant (p>0.05).

In this study, 600 one-day Japanese quails were assigned to six treatments with five replicates of 20 chicks per replicate in 2×3 factorial arrangement based on a completely randomized experimental design. Two levels of L- arginine (the recommended level of NRC and 10% higher than the recommended level by NRC) and three levels of Guanidino acetic acid (GAA) (0, 0.6 and 1.2 g/kg diet) were used in this study. Body weight and feed intake were recorded at the end of the experiment. On day 42, blood samples from two chicks of each replicate were taken from wing vein for some blood metabolites measurements. Then, thechicks wereslaughtered for carcass and internal organs investigations. L-arginine supply at 10% over NRC recommendation increased daily feed intake, and improved body weight gain and feed conversion ratio significantly (P<0.05). L-arginine supply at 10% over NRC recommendation and 1.2 g GAA/kg diet increased feed intake and improved feed conversion ratio (P<0.05). The relative weight of breast and thigh increased and abdominal fat decreased significantly by L-arginine supplementation (P<0.05). The main effects of L- arginine and GAA on blood metabolites were significant (P<0.05), with a reduction effect on cholesterol, triglyceride and VLDL concentrations and enhancement effect on HDL content. L-arginine supply at 10% over NRC recommendation with 0.6 and 1.2 g GAA/kg diet significantly decreased blood cholesterol, triglyceride and VLDL and increased HDL concentrations in compared to those fed L- arginine at NRC recommendation (P<0.05). Therefore, the findings of this study showed that providing extra L- arginine than the NRC recommendation with 0.6 g GAA/kg diet significantly improved performance and decreased blood serum cholesterol, triglyceride, and VLDL in Japanese quails (P<0.05).

In order to investigate the effects of Galbanum essential oil (GEO) and xylanase on performance and intestinal microflora of broiler chicks, a total of 160 one-day old chicks (Ross 308 strain) were used to four dietary treatments based on a completely randomized design in a factorial arrangement. The factors included were xylanase (0 and 0.2 gr/kg of diet) and GEO (0 and 0.1 gr/kg of diet). During the experimental periods (0-10 d, 11-24 d and 25-42 d), body weight gain (BWG), feed intake and feed conversion ratio (FCR) were measured. At days 21 and 42 of age two chicks from each replicate were slaughtered to determine carcass characteristic and ileal microbial populations of E. coli and Lactobacillus. Adding enzymes to the diet increased BWG in growing period and improved FCR in the growing and in the entire period of the experiment. At 21 day of age, GEO supplementation alone or GEO and xylanase as mixed significantly (P

Twenty-four Raeini cashmere goat females (2 and 3 years of age and 35.0±1.4 kg BW) were used to determine effects of melatonin implants and bromocryptine on fiber growth rate (length), cashmere and hair diameter and fleece production. A completely random design was carried out. Four groups were formed: 1) control, 2) melatonin implant, 3) bromocryptine injection and 4) melatonin implant bromocryptine injection. The experimental goats received melatonin implants subcutaneously 18 mg/kg BW at first and repeated after 40 days, group 2), bromocryptine ( 0.5 mg/kg BW per 3 days; group 3) and melatonin implant and with bromocryptine; group 4 ). All goats were fed a balanced diet under the same environmental and natural photoperiodic conditions in a 60-day, from February to March. Overall mean fleece weight were 607.4, 600.3, 523.3 and 471.3g, for bromocryptine, melatonin溺⚡쫲ꛘ, melatonin and control groups, respectively, being greater for bromocryptine and melatonin溺⚡쫲ꛘ than for the other groups (P

Improvement of hatchability in aging broiler breeder has economic justification.
The main objective of this study was to determine the effect of dietary Anethum graveolens essential oil on egg quality, some plasma metabolites and hatchability in broiler breeder hens.
A total number of eighty hens and eight cocks from Ross 308 strain of 105 weeks old were divided into four groups with two replicates within each (10hens 1cock). The diets were supplemented with out essential oil (Control) and with 10, 20 and 40 ml essential oil/100kg diets for four weeks.
There were no significant differences among the groups in Haugh unit and yolk index. While, there were significant differences in egg weight, egg shape index, shell thickness, shell ratio, yolk color and shell weight. Plasma triglyceride, high density lipoprotein cholesterol (HDL-C) and egg yolk cholesterol concentration were not influenced by dietary essential oil of Anethum graveolens. Whereas essential oil increased plasma cholesterol significantly, it also significantly decreased plasma glucose. Hatchability and fertility were positively affected by supplementation of essential oil in the diet.
Results of this study showed that supplementing diet with Anethum graveolens essential oil improved hatchability of total eggs set of broiler breeders.

Despite the critical importance of minerals as a fractional component of hormones, enzymes, tissues and body fluids, they are not produced in the animal body and must be fed by the diets. This study aimed at determining the basic data of serum mineral (SM) and thyroid hormone (STH) concentrations and their relationships in different gender and age groups of Caspian miniature horses fed diets with different mineral contents. This research was conducted on twelve horses using a balanced change over design with four treatments (9 replicates per treatment) in 3 periods and 4 blocks (two genders and two age groups

Heat stress is one of the most important environmental stressors challenging poultry production worldwide. Understanding and controlling environmental stressors is crucial for successful poultry production.
The aim of the present study was to investigate the effects of melatonin supplementation and darkness regime on reducing the negative effects of heat stress in broiler chickens.
A total of 400 broiler chickens (Arian) were obtained and subjected to four different groups. The control chickens were grown in normal conditions without receiving any treatment. The positive control birds were grown similar to the control but exposed to an acute heat stress for 6 h/d from days 35 to 40. The dark group chickens were reared under a dark schedule and exposed to heat stress. The birds of the fourth group were reared similar to the positive control but received 40 ppm melatonin in the diet from days 30 to 40 of age. Dead birds were autopsied. The weekly growth performance of chickens was determined and blood samples were taken for hormonal analysis.
The number of dead birds due to heat stress was significantly decreased in chickens subjected to the dark program and/or those which received melatonin in the diet compared with those of positive control chickens. Such differences were accompanied with the significantly lower levels of plasma T3, T3/T4 and corticosterone in these groups of chickens. Additionally, plasma thiobarbituric acid reacting substances level was significantly higher in positive control broilers compared to their counterparts.
Our findings indicate a reduction of metabolic rate and heat production in dark regime and melatonin supplementation that can reduce the side effects of heat stress and, therefore, reduce the mortality rate.

This experiment was conducted to investigate effects of blood uric acid on performance and resistance of broilers under heat stress. 200 day old Ross 308 chicks were used in a completely randomized design with 5 treatments, 4 replicates and 10 chicks in each replicate. Chickens were fed from 24 days of age with diets containing 0.35 (U0.35) and 0.70 (U0.70) % of urea and 1.29 (A1.29) and 2.58 (A2.58) % of di-ammonium citrate and without urea or di-ammonium citrate. During the experiment, weight gain, average feed intake and feed conversion were measured weekly. Heat stress was applied with exposing the birds to a 35 ± 1 ˚C temperature from 28 days of age onwards. At 27 and 41 days of age, two birds from each replicate were selected randomly and blood samples were collected from brachial vein to determine the concentration of serum uric acid and malondialdehyde. The results showed that at 36-42 days of experiment, the FCR of A2.58 (1.96) was significantly (P0.05). The content of serum uric acid of U0.7 at 27 and 41 days (2.38 and 6.03 mg/dL respectively) was significantly higher than the control (P

A total of 130 Arian broiler chicks were used in this study in order to assess the effects of tryptophan, melatonin and dark regimes on the performance and blood parameters of chickens exposed to heat stress. The chicks were allocated to the experimental units in an unbalanced completely randomized design. The treatments were control group, 40 mg of melatonin per kg of diet from 30-40 days of age and 0.04% of tryptophan per kg of diet from 10-40 days of age and dark period from 10-40 days of age. All treatments were daily exposed to heat stress (39±1C°) for 6 hours from 35-40 days of age. Minimal weight gain was achieved in the third weeks of age and the birds that received tryptophan treatment have highest weight in fourth weeks of weights (P<0.05). The highest level of high density lipo-protein related to tryptophan and melatonin treatments at 40 days (P<0.05). The level of T3 in darkness treatment at 35 days and TBARS level in darkenss and melatonin treatments were decreased (P<0.05). Results of this experiment showed that melatonin supplementation however of its usage after 30 days but had better influence in performance and blood parameters such as increased levels of high density lipoprotein protein and lower of thiobarbituric acid.

The effect of different levels of dried purslane powder (DPP) in broiler diets on performance, immune response and some of blood factors was studied with 160 one day old chicken Ross 308 in a completely randomized design with four treatments (diets included with levels 0 (control), 2.5, 5 and 7.5 percent DPP), four replicates and 10 chicks in each replication. At 22-42 and 1-42 days different level of DPP resulted in a significant increase in the daily body weight gain and daily feed intake. Birds that were fed with 5 and 7.5 percent of DPP have a better feed conversion ratio compare with the control group (P

The effect of melatonin and bromocryptine on body weight، fibre shedding and cashmere traits was investigated. The Twenty four Raeini goats females (2-3 years old) were allotted to four treatments (n=6/group): control (C); melatonin (MI) implant (18 mg at first and repeated after 40 days); bromocryptine (B) injection، (0. 5 mg/kg BW per 3 days) melatonin and bromocryptine implant and injection (MIB). All goats were maintained under natural photoperiodic conditioned of short day photoperiod (8 h light and 18 h dark)، for 2 months. Fibre was harvested by using wooden combs and each goat was combed four times at two week intervals، from 23th February to 8th March. Combed fibers were 23. 3، 15. 7، 17. 0 and 21. 3 % for MI، B and MIB treated and C groups (P>0. 05).. Cashmere fiber diameter (CFD) for MI group (21. 4 um)، was higher than the other C، B and MIB groups 20. 2، 19. 9 and 19. 8 um (P<0. 01). The CV of CFD was significant and higher in C group compared with the other groups (P<0. 05). These results suggest that hormone treatment improve uniformity of cashmere diameter.

Searching for factors that reduce the adverse effect of heat stress (HS) on broiler performance has particular importance. The present study was designed to investigate the influence of dietary melatonin, gamma-amino butyric acid (GABA) and dark period on growth performance, carcass characteristics and blood parameters of broiler under heat stress condition. A total of 143 one-day-old chickens (broiler line Arian) were used in an unbalanced completely randomized form with 4 treatment, 13 experimental units and 11 birds per experimental unit. The treatment consists of 40 mg of melatonin/kg diet from the age of 30 to 40 days, 100 mg (GABA)/kg diet from the age of 10 to 40 days, dark of period from 10 to 40 days of age and control. All treatments were kept a circular HS (40±1°C) for 6 h from 35 to 40 post hatch. Weekly growth performance of chickens was determined and blood samples were taken, on days 10, 30 and 40 of age for measurement of glucose, cholesterol, triglyceride, HDL and LDL parameters. On days 35 and 38 of age T3, Thiobar Butyric Acid Reacting Substances (TBARS) and corticosterone parameters were measured. Data were analyzed by using of GLM procedure of SAS. The diet supplementation of GABA increased feed intake in the second (p<0.01) and third (p<0.05) weeks of age. Dark period reduced body weight in the third weeks of age (p<0.05). The treatment of GABA in the fourth week increased body weight compared to the control group (p<0.01) and a significant decrease for FCR was observed in the fourth weeks (p<0.01). Addition of GABA in diet increased serum glucose at 30 days of age (p<0.01), in the both melatonin and GABA treatment groups serum HDL was increased at 40-day-old (p<0.01). Control chickens showed significantly (p<0.01) higher TBARS compared to the experimental group birds at 38-day-old. The results demonstrated that dietary GABA had the most beneficial effects in reducing the adverse effects of heat stress on the broiler chicken.

Experiment was conducted to study the effect of different antibiotics on sperm quality of ram by a completely randomized block design using 23 factorial arrangement with 2 block and 4 observations in each experimental units. Factors include three antibiotics named Gentamycin (G), Lincomycin (L) and Ampicillin (A) that were used at two different levels including zero and, respectively 5, 10 and 2.5 μg / ml of diluents. Tris-based and skimmed milk-based diluents were considered as block1 and block2 respectively. Semen was collected from four rams in 8 times. Samples were aggregated and divided into eight equal parts. The different levels of antibiotics were added to each part. Samples temperature was reduced at a rate of 0.25° C/min t 5° C and was stored at this temperature for 72 hours. Sperms evaluations were performed at 0, 24, 48 and 72 h after storage. The interactions between antibiotics on the progressive mobility, plasma membrane integrity and viability of sperm were significant (P<0.05).After 0,24,48 and 72h of storage, progressive motility(78.19, 66.26% and 54.52%), plasma membrane integrity(85.12%,75.12% and 62.62%) and viability of sperm(86.12% 78.38% and 70.62%) in a0g0l10 (Lincomycin 10μg / ml of diluents) were significantly (P<0.05) higher than other treatments except a0g5l0 (Gentamycin 5μg / ml of diluents) at 24, 48 and 72 h after storage. However the characteristics of a0g0l10were significantly higher than a0g5l0 at time zero. From this study we concluded that using Lincomycin 10μg / ml had the most effect on quality of spermatozoa during storage at 5° C.

In order to investigate the effect of different levels of the additive containing Artichoke premix concentrated (APC) on growth performance, serum cholesterol level, carcass characteristics and immune responses of broilers two separate trials were conducted. In the first trial, APC was added at three levels of 0, 100 and 200 gr/ton diet during the first 21 days of growing period. One hundred and fifty unsexed day old broiler chickens of Ross strain were randomly divided in three groups with 5 replicate of 10 chicks in each cage, by a completely randomized design. At the end of each week, the birds were weighed individually and feed conversion ratios calculated. In order to determine serum cholesterol level, at day 21 blood sample was taken from 15 chickens per treatment. At the end of the 42nd day, 5 birds from each group were randomly selected and slaughtered for investigation of carcass characteristics. In the second trial, the effects of APC at 150gr/ton feed were studied on growth parameters and immune function of broiler chickens in a commercial farm. The results showed that application of APC in a level of 200 gr/ton diet significantly increased body weight of chickens at the first (p

The present study deals with the effect of different levels of synbiotic on egg production and quality, blood parameters, hatchability and yolk cholesterol in broiler breeder hens.

The aim of this study was to determine the best level of synbiotic in the diet of broiler breeder hens.

The study was conducted based on a completely randomized design with 4 treatment groups, 2 replicates and 10 controls in each experimental unit. The experimental rations were containing 0 (control S0), 0.05 (S0.05), 0.1 (S0.1) and 0.2% (S0.2) synbiotic. Egg quality and weight were measured daily. Blood parameters, laying rate and hatchability were measured weekly. Yolk cholesterol, ovarian weight and number of ovarian large follicles were evaluated at the end of the experiment. The data were analyzed using GLM procedure.

The results showed that yolk index in group S0.1 was significantly lower (p<0.05) than groups S0.05 and S0.2, but was not statistically different from the control (p>0.05). Also, synbiotic had no significant effect on other egg quality traits, egg weight and hatchability (p>0.05). Addingy synbiotic supplement to diet reduced significantly the laying rate, ovarian weight and number of ovarian large follicles in the group S0.2 compared with the other groups (p<0.05). Synbiotic significantly increased plasma glucose concentration (p<0.05), but plasma triglyceride, HDL and yolk cholesterol concentrations were not influenced by dietary symbiotic (p>0.05). Furthermore, plasma cholestrol concentration (last week) in groups S0.1 and S0.2 were significantly lower than control group (p<0.05).

The results showed that it would be proper to use 0.1% synbiotic in the diet of broiler breeder hens.

Calving records from April 1996 to December 2005 comprising 31863 calving events of 1173 dairy cows in a large commercial dairy herd were used to evaluate the effects of heat stress، using temperature-humidity index (THI) on milk yield and composition and reproductive performance of Holstein dairy cows under humid climatic conditions of Rasht in Iran. THI values were grouped into six groups: 30-40 (THI1)، 41-50 (THI2)، 51-60 (THI3)، 61-70 (THI4)، 71-80 (THI5) and 81-90 (THI6). Dairy cows in THI6 had lower milk and fat yields than other groups of THI، but cows in THI1 and THI2 had the greatest amounts of milk and fat yields، respectively (P<0. 05). However، dairy cows in the second group of THI had lower percentages of fat than the sixth group of THI (P<0. 05). Spring-calved cows had longer days open than cows calved in other seasons (P<0. 05). Also، summer-calved cows had greater number of services per conception and lower conception rates than cows calved in other seasons (P<0. 05). Dairy cows within the THI5 which calved in spring and/or calving years 2004-2005 had the longest days open (P<0. 05). Cows in the second group of THI had the greatest and the lowest number of inseminations and conception rates compared with other groups of THI، respectively. The results of the present study indicated that summer heat stress negatively affected milk yield and composition and reproductive performance of dairy cows. Therefore، application of management interventions to ameliorate the effects of heat load on the performance of dairy cows could be needed in certain periods of the year under the climatic conditions.

The objective of this study was to investigate the effect of different levels of benzoic acid on performance and carcass characteristics of broiler chickens. To this purpose 120 one-day-old Ross 308 chickens were examined with a completely randomized design with 4 treatments, 3 replications and 10 sub sampling that were reared for 42 days. Dietary treatments included of the 0, 0.25, 0.5 and 1 percent levels of benzoic acid. Properties were measured included weight gain, feed intake and feed conversion rate. Dietary supplementation of benzoic acid significantly decreased feed intake of chickens (P<0.05) and the highest feed intake observed in control group. There was no significant difference between BA0.25 and BA0.5 groups in terms of body weight gain (P>0.05). Supplementing 1% benzoic acid in the diet resulted in significant decrease in body weight gain (P<0.05). Use of 0.25 and 0.5percent benzoic acid in the broilers diet in contest of control group significantly decrease FCR (P<0.05). Also inclusion of benzoic acid in the diet resulted in significant decrease breast to carcass weight ratio in 0.5percent treatment (P<0.05) but thigh to carcass weight ratio significantly increased in the treatment of 0.5 percent of benzoic acid than control group. Regarding to present results, suggested that use of 0.5 percent dietary supplementation of benzoic acid in broiler chickens is possible without negative effects on performance and carcass characteristics.