Year:2005 | Volume:18 | Issue:2 (67 IN ANIMAL AND FISHERIES SCIENCES)|Papers Count:16

For Varroa mite (Varroa destructor) control, as an important pest of honey bee (Apis mellifera L.) chemical control methods have been used widely yet. These methods not only cause contamination of hive products but also make varroa resistance to chemical acaricides. Nowadays much of the researches are focused on non-chemical control methods such as producing resistance races of honey bees. One of the important factors for honey bee resistance to this mite is shortening the capping period of sealed brood cells that the mite can not complete its metamorphosis cycle and reproduction and decrease its population. In this study, honey bee populations from Isfahan, Tehran, Markazi and Ghazvin provinces were compared for capping period of brood cells. The statistical design for evaluating this resistance mechanism was a complete randomized design. Treatments were colonies of four above mentioned provinces from the National breeding research project that carried out on four replications. Each replication included a hive with an average of seven frames of bees that in certain time each queen was confined on a comb in a cage with queen excluder. After 24 hours the oviposited portion of each comb was marked. Within the ninth day the brood cells were capped and the exact time of capping was recorded. Eleven days later the frames were transferred into the incubator (34±1ºC and 60% RH) and the exact time of brood cell opening and capping period was recorded. Results showed that there is no significant difference between the duration of capping period in four provinces. If we compare the average of total duration of capping period with each other, the difference of 5 hours exist within colonies of Ghazvin with 290 hours (The longest average of capping period) and Markazi with 285 hours (The shortest average of capping period). The more smaller capping period cause varroa mite not to be able to complete its developmental period and as a result its population goes down. Results showed that colonies of Markazi and Isfahan provinces had lower mite population.

Serum magnesium concentration (Mg Conc.) in 200 dairy Friesian calves (I03 male and 97 female) aged from birth to 4 months in different seasons in 2001-2 was investigated to: 1- Determination and comparison of serum Mg concentration in female and male dairy calves, 2- to compare the effects of age and season on serum Mg concentration in calves, 3- the effects of season, age and sex on calves' serum Mg concentration, 4- determination of probable sub-clinical hypomagnesemia in dairy calves. Number of females in Spring, Summer, Autumn and Winter were 24, 23, 22, 28 and males were 24, 18, 29 and 32, respectively. Number of females aged 1, 2, 3, and 4 months old were 48, 21,12 and 16 and males were 32, 31, 27 and 13, respectively. Serum magnesium concentration was estimated in mmol/l using xylidylblue test and magnesium kit (Parsazmun) by spectrophotometer (Pharmacia, LKB, Novaspec, England) of 500 wavelength. Panacea statistical program, normal distribution, ANOVA and Factorial ANOVA were used to analyse the data. Mean serum Mg concentrations in female and male calves were 1.06 and 0.79 mm01/1, respectively which was significant (p<0.001). Mean serum Mg concentrations in Spring, Summer, Autumn and Winter were 0.82, 0.96, 0.95 and 0.93 mmol/l, respectively. ANOVA showed no differences between seasons, except for males that were differed between Summer and Autumn (p<0.001) and for females between Winter and Summer (p<0.001). Mean serum Mg concentrations in females aged 1,2,3 and 4 months were 1.29, 0.82, 0.84 and 0.67 mmol/l and for males were 0.99, 0.78, 0.72 and 0.52 mmol/l, respectively. Serum Mg concentrations in calves were differed in different ages (p<0.001). Mean serum Mg concentration in 4 months males was differed (p<0.005) from one & two months old and serum Mg concentration in 4 months females was differed (p<0.01) from one month old. Factorial ANOVA between serum Mg concentration and season, age and sex showed significant effects (p<0.01) between these variables. It can be concluded that mean serum Mg concentration in females was greater than males. Season had no effect on mean serum Mg concentration in female and male calves. Serum Mg concentration decreased with age and in males reached up to subclinical hypomagnesemia at 4 months of age. Season, age and sex had significant effect on serum Mg concentration. Male calves at 3 months of age in winter and Spring are susceptible to sub-clinical hypomagnesemia.

The effect of genetic and non-genetic factors on body weight at 6 weeks (BW6WT), egg weight (EWT), age at sexual maturity (ASM) and egg production from 25 to 50 weeks (EP) of a commercial broiler line were investigated using restricted maximum likelihood procedure through estimation of direct and maternal additive genetic and common environmental variances. Six different animal models were taken into account by including maternal direct additive or environmental effects in the models of analysis. Likelihood ratio test was used to determine the most appropriate model. For BW6WT, maternal additive and common environmental effects together with the covariance between direct and maternal additive genetic effects were significant. For this trait, direct heritability (h2a), maternal heritability (h2m ), maternal environmental variance as a proportion of the phenotypic variance (C2) and the correlation between direct and maternal additive genetic effects (ram) were 0.350, 0.050, 0.040 and-0.670, respectively. For EWT, ASM and EP, only maternal additive genetic effects were important, in addition to the direct additive genetic effects. The estimates of h2a and h2m were 0.470 and 0.130 for EWT, 0.150 and 0.060 for ASM, and 0.240 and 0.05 for EP, respectively. The results of this study indicated that ignoring the maternal effects in the analysis tended to overestimate direct additive genetic variance and heritability for all traits.

The shearing time (shorn once and twice in year) effected on wool characteristics were studied. 58 female Baluchi sheep 1-3 ages from Abas Abad station in east-north of Iran were selected and divided into once and twice shearing groups for two years. Wool samples from right midside were collected and the traits fleece weight, staple length at shoulder, flank and rump regions, fiber length, average fiber diameter and diameter coefficient of version, tenacity and breaking force were studied. The data were analyzed by repeated measurement and general linear model (GLM) using SAS software package. The Spring fleece weight (1.89±0.05 versus 1.57±0.05 kg) and staple length (9.32±0.22 versus 8.01±0.19 cm) and variation fibre length for once or twice shearing time res were (p<0.0005) significant. The total fleece weight of twice (2.23 kg) was more than that of once shorn (1.85kg) but was not significant.

This study was performed to evaluate using different levels of poultry by-product meal (PBPM) in broiler feed. A trial was designed with 228 Arian"s commercial broiler chicks in the same weight and using Completed Randomized Design with 4 treatments and 3 replacements. Number of chicks per every pen was 19 and age of them was 7 days at the beginning of trial.Experimental diets contained 0,2, 4 or 6 % of PBPM. The levels of energy, protein and other nutrients were the same between of diets and controled by breeding catalogue. Water and food were fed adlibitum.Two chicks were selected and slaughtered for the carcass characteristics at the end of trial. Traits that considered were: Weekly gain and feed intake, feed conversion, final weight, mortality and carcass characteristics. Data were tabulated and analysed by SAS program, then statistical parameters and differences were estimated. So treatment means were compared by Duncan's Multiple Range Test. According to the results, overal feed intake and gain were significant between all of treatments (p<0.05), but other traits such as feed convertion, mortality percentage and carcass traits were not significant (p>0.05). As a finally result, using 6% of PBPM in diets decreased feed intake and feed costs, also promoted feed conversion and gain. Cost per 1 kg of live weight for all of treatments was calculated. According to the results level of 6% PBPM was the best and has the lowest cost (3446 Rials), and control group has the highest cost (3954 Rials). Levels of 4 and 2 % PBPM (respectively with 3526 and 3671 Rials) were moderate.

Isfahan province with 1.5 million immigrant sheep and goats has one of the highest populations of immigrant sheep & goats in Iran and nomadic people are depending on them as source of meat and milk. Babesiosis is a problem of these sheep and goats and in them the disease can be fetal. Sheep & goats act as reservoirs for the babesia spp. and no studies have been done in Isfahan. In this parasitological survey, prevalence of babesia spp. was studied in immigrant sheep & goats and nomadic people of Isfahan area in Iran from 2002-2003. In immigrant sheep and goats a total of 715 blood smears originating from 3 area and 57 flocks were investigated for the presence of babesia spp. In The 196 smears that were found posetive for babesia spp., 22.5% B.matasi and 77.55% B.avis were detected. The study revealed that the infection rate for Babesia avis and Babesia matasi were 152 (21.26%) and 44(6.15%) respectively. In nomadic people 500 blood smears were taken from patients humans with clinical signs same as fever, weakness head ache and muscular pain. All blood smears were investigated for babesia spp. but fortunately we could not find parasite in any of them.

Aquatic fungi (saprolegnia) are ubiquitous in natural water supplies of fish hatcheries often causing serious disease and problems. In this research, the therapeutic index of formalin, malachite green and potassium permanganate on Asipenser persicus eggs was determined and compared. Formalin, malachite green and potassium permanganate were evaluated in three trials approximately 30 hours after fertilization, using following concentration formalin-0.4, 0.8, 1.6, 3.2, 6.4 and 12.8, malachite green -0.2, 0.4, 0.8, 1.6, 3.2 and 6.4, potassium permanganate, 20, 40, 80, 160, 320 and 640 ppm. Each trial consisted of eighteen 1.8-lit aquaria for six treatments (low to high drug concentration treatment) with three replications per treatment. Therefore the total number of treatments with three untreated treatments was 57. All trials used eggs that were derived from the same egg mass with 77% fertilization rate. 100 eggs of egg mass were randomly assigned to each aquaria in order to treat eggs for 30 minutes. Then eggs transferred to separated incubator and kept there for 96 hours. During 96 hours, infected, hatched and non-hatched eggs exactly enumerated. The difference between dead eggs mean in untreated groups and other treatment used for lethal concentration calculations and the difference of infected eggs mean in untreated groups and other treatments means used for therapeutic concentration calculated by using pharmacologic calculation program and were determined the LC50 EC50 and therapeutic indices of candidate fungicides. The therapeutic indices of potassium permanganate, malachite green and formalin were 5.37, 2.25 and 0.99 respectively. In conclusion, Potassium Permanganate was shown to be safer than malachite green and formalin in controlling saprolegnia in A. persicus eggs. 

This project designed to determine population dynamics of banana shrimp stocks (Penaeus merguiensis) by swept area method from Bandar Abbass to Sirik coastal waters of Hormozgan province in 2000-2002. The sampling was carried out once a month .The carapace length frequency analysis showed that mean on Spring season upswing. The growth coefficient (k) was 1/8 for female and 1/6 for male. The asymptotic carapace length (CL∞) was 45/5 mm and 35/5mm for female and male respectively. Mortality rate for female was higher than male. Exploitation rate was 0.49 and 0.40 for females and males respectively.

This experiment was carried out to study variations in some of the agronomic traits and feeding value of Hamedani cultivar of alfalfa during different stages of growth in the second cutting. Plant height, dry matter and leaf to stem ratio were measured and the chemical composition of samples taken during different stages of growth (prebudding, initial budding, full budding, initial blooming and full blooming) was determined by approximate analysis. Digestibility of dry alfalfa in the stages of initial budding, initial blooming and full blooming was measured by In vivo method using four Mehraban male lambs. An average plant height of 24.36 centimeters in prebudding stage reached 60.18 centimeters in full blooming stage. Plant height differences between the stages of growth was statistically significant (p<%5). Dry matter percentage of the whole plant increased with the advancement of growth stages and changed from 20.18 ercent in prebudding stage to 27.10 percent in full blooming stage with an statistically significant difference (p<% 5). Dry matter percentage of leaf and stem showed a variation similar to the whole plant. The highest amount of organic matter in the whole plant was 90.47 percent in initial blooming stage and the lowest amount was 89.62 percent in full blooming stage, but the difference was not statistically significant. The highest amount of crude protein in the whole plant (23.79 percent) was observed in the first growth stage (prebudding) and the lowest amount (17.06 percent) in the last growth stage (full blooming) with an statistically significant difference (p<% 5). The amount of crude protein in stem and leaf showed a similar trend with the advancement of plant age. Percentage of crude fiber in the whole plant increased with the advancement of age and changed from 20.12 percent in prebudding stage to 27.50 percent in full blooming stage with an statistically significant difference (p<% 5). Percentage of dry matter digestibility decreased from 62.78 percent in prebudding stage to 59.10 percent in full blooming stage but the difference was not statistically significant. A similar trend was observed for digestibility of crude protein. Digestibility of crude fiber showed no distinct trend and no significant differences were observed, however, the highest amount of digestibility was observed in initial blooming stage (57.81 percent) and the lowest amount in initial budding stage (53.02 percent). Alfalfa energy yielding value based on total digestible nutrients (TDN) decreased with the advancement of age and changed from 61 percent in initial budding stage to 58 percent in full blooming stage but the difference was not statistically significant. On the basis of the results obtained, it seems that in order to produce feedstuff with acceptable quality and quantity, cutting alfalfa between initial bloom (%10 flowering) and full bloom (% 50 flowering) stages will improve the yield per hector.

In order to evaluate the production perfonnance of six hybrids broiler (Arborakers, Aryan, Cub, Hubbard, Lohaman and Ross) an experiment was conducted. Four hundred and eighty birds were allocated in a completely randomized design with 4 replicates and 20 birds per replicate from day old to 42 days of age. The performances of birds including growth rate, weight gain, food intake, feed efficiency, livability and production efficiency ratios were measured during the production period in order to compare the hybrids. Statistical analysis of performances criteria showed that there was significant differences in weekly weight gain among hybrids (p<0.01), the weight of Cubs were higher than others by the end of 42 days of experimental periods while Hubbard had the lowest weight gain. Birds also differed significantly in the amount of food intake (p<0.05), Ross had the lowest food intake and Cub had the highest intake. Since the weight gain was not similar and proportional to food intake, the hybrids also differed significantly in their feed efficiency ratio (p<0.01). Cub had the lowest feed efficiency ratio while Lohman had the highest. There were no significant differences in livability ratio among the hybrids. The production efficiency ratio, criteria that is relatively better indicator of performances (consisting of most performance and production criteria) was highest for Luhman, Weekly growth rate ratio and feed efficiency of all hybrids declined after 5th weeks indicating that there is relatively lower profit margin after 42 days of age. There were no significant differences in carcass ratio (to live body weight at the end of experiment), breast and leg ratio (to carcass weight) among hybrids examined. The abdominal fat percentage was lowest for Ross and highest for Lohman. Chemical analysis of carcass showed that Hubbard had the lowest fat percentage and highest protein content. Arborakers on the other hand, had the highest fat content while Ross had the lowest protein content in its carcass.

Urine magnesium (Mg) and creatinine concentrations in 93 dairy Holstein and hybrid cows in Urmia was investigated to determine the concentrations of Mg and creatinine in urine and possible diagnosis of sub clinical hypomagnesaemia. Creatinine assessment was considered as the normal activity of kidneys. Urine samples were collected by using spontaneous urination, rectal examination and urine catheterization into 10 ml tubes. Urine Mg and creatinine concentrations were calculated using Mg and creatinine commercial kites in spectrophotometer. Mg and creatinine were observed in all samples. The range for Mg and creatinine were 0.05-7.71 mmol/l and 15.6-30 mg/dl. Urine Mg classified into> 1.5 mmol/l as the cows with high serum Mg concentration, 0.42-1.49 mmol/l for the cows with suspectible to low serum Mg concentration and <0.41 mmol/l as the cows with hypomagnesamia. The distribution and percent of experienced cows were 78 and % 83.87, 10 and %9.67, 5 and %6.45, respectively. Mean±SE of urine creatinine in three groups were 22.7±3.4, 20.6±2.7 and 21.1±4.2, respectively. The values were in recommended range and differences were not significant. Thus, it can concluded that Mg can excreted into urine healthy cows and its concentration depends on the concentration of Mg in blood. Low urine Mg concentration probably considered as the cow at the risk of sub clinical hypomagnesemia when kidneys to be at health.

Lead is one of the oldest metals known to man and Industrial pollution is one of the most important sources of lead.Hair lead levels are diagnostically useful for lead pollution around oil and petrochemical industries. Hair samples (67 in each season for each species) were obtained from cattle in a radius of one to ten kilometers of Shiraz oil and petrochemical industries. Hair samples of different species (34 in each season), which were obtained, far away from these industries and not close to main roads served as control samples. Hair samples were subsequently digested and analyzed for their lead content by atomic absorption spectrophotometry. Overally, results revealed that the mean hair lead content of cattle (6.5±1.2ppm) around Shiraz's oil industries (within radius of 1.5 Kilometers) were significantly higher than mean hair lead content of cattle (3.1±0.9ppm), around Shiraz's petrochemical industries (p<0.05). Meanhair lead content of control cases throughout the year were 1.1±0.3ppm, 4.48±1.09ppm and 3.37±0.35ppm Which were significantly lower than mean hair lead content of cattle around Shiraz's oil and petrochemical industries (p<0.05). These levels show that lead pollution around Shiraz's oil industries can be a serious problem and must be considered in future.

Escherichia coli is one of the common agents of diarrhea in new born calves. Bacteria has characteristics which from them, the presence of fimbriae is very important. The purpose of this research was determination of prevalence of F5 fimbriae in isolated bacteria from diarrheal calves. In this research, 234 fecal samples were collected from diarrheal calves with less than one month old. After isolation of E.coli, the presence of F5 fimbriae in isolated bacteria was examined by specific antiserum (F5 antiserum). From 234 samples 21 cases (9%) were positive. Frequency of positive cases was 19% in calves with less than 5 days old and 5% in calves with more than 5 days old, also frequency of positive cases in rural dairy farms (20%) was significantly higher than industrial dairy farms (2/6%). According to results, E. coli plays role in calves diarrhea in Arak city and it must be noted.

Amirkelayeh wetland is an international wetland, located in Guilan province (Iran). Fifteen fish species inhabit in the wetland, of these, Perch (Perca fluviatilis , L. 1785) is the most abundant species. The present study was carried out on parasites of perch in the wetland from March 2001 to February 2002. The objective was the study on parasite communities of perch and also calculating the prevalence mean intensity, range, abundance and dominance of the parasites. Haphazard sampling was carried out using gill net and ect. Standard necropdy and parasitology methods were used for finding the parasites. The speciemens were for finding the parasites. The speciemens were fixed in 10% buffered formalin and stained with acetocarmine. The nematodes were cleared in lactophenol. The parasites were identified by parasite identification keys. In the present study, five parasite species were found in the samples consisting of Camallanus lacustris, (prevalence = p = 36/2%, mean intensity = mi = 3/75), Diplostomum spathaceum , (p= 8/59% , mi=l ), Lemaeasp ., (p = 4/29% , mi = 2/57%), Argulus sp ., (p = 0/61% , mi = 1 ) and Dactylogyrus sp ., ( P =0/61% , mi = 5 ). In this study, C. lacustris , Argulus sp. and Dactylogyrus sp. are reported for the first time from perch in Iran. The prevalence of C. lacustris was more than other parasites. As a whole, the diversity of parasites in Perch was less than in the other predatory fish (such as pike) in Amirkelayeh wetland.