مجله علوم دامی ایران
سال چهل و سوم شماره 2 (تابستان 1391)

The effect of different levels of zinc and copper organic supplements on performance, plasma copper plus zinc status, serum Alkaline Phosphatase (ALP), Ceruloplasmin (CP) activity as well as vitamin ¬A concentration was studied in 25 Mehraban male lambs each of 5-6 months of age and 30/64±3/47kg of live weight. The following five dietary treatments were used: 1) Control (base diet with no addition of either adding zinc or copper proteinate supplements), 2) base diet+20 mg/kg of zinc+10 mg/kg of copper, 3) base diet+20 mg/kg of zinc+20 mg/kg of copper, 4) base diet+40 mg/kg of zinc+10 mg/kg of copper, 5) base diet+40 mg/kg of zinc+20 mg/kg of copper. The Zn and Cu supplementations didn’t exert any significantly effect on the performance but induced significant increase in the plasma levels of copper and zinc (P=0/0001), however no significant difference was observed between the supplemented treatments. Regardless on the levels of Zn and Cu organic supplementation, CP activity was increased. ALP activity was increased numerically but no significant difference was observed between the treatments. The supplementation indicated a positive significant effect on serum vitamin A concentration (P=0/041). The highest levels of zinc and copper (5treatments) induced highest serum vitamin A concentration.

This study was conducted to determine the effects of different levels and sources of copper supplementation on hematological values, ceruloplasmin and plasma copper, zinc and iron status in Mehraban male lambs. Twenty growing lambs were randomly allotted to four different treatments. Treatments consisted of 1) 10 mg/kg Cu in the form of CuSO4, 2) 20 mg/kg Cu in the form of CuSO4, 3) 10 mg/kg Cu in the form of Cu-Proteinate and 4) 20 mg/kg Cu in the form of Cu-Proteinate, administered daily with the basal diet. Blood samples were taken via the jugular vein on days 0, 7, 14, 28, 57 and 65 then analyzed for hematological parameters. The samples taken on days 28 and 65 were also used for a determination of serum ceruloplsmin activity as well as plasma Cu, Zn and Fe concentrations. There was a significant (P < 0.001) negative correlation observed between plasma Cu and Fe (r = -0.604), and as plasma Cu increased (up to d 65) plasma Fe concentrations decreased in all the treatments. Copper source exerted a significant effect on ceruloplasmin concentration (P < 0.05). on d65, the 20ppm Cu-proteinate treatment carried the highest ceruloplasmin concentration (P < 0.05). Copper level exerted a significant effect on RBC, PCV and Hb, with the treatment of 20 ppm level causing higher values (P < 0.05). No clinical or hematological signs of copper toxicity were observed throghout the study. There was an evidence of adverse effects of high Cu supplementation on RBC count, PCV and Hb at the conclusion of the experiment. It can be concluded that the obtained result may be due to Cu interaction with iron as well as its effect on iron metabolism and hematopoesis.

To finding out the genetic structure of Iranian native horses, as animal blood samples were obtained from diverse areas of Iran, in addition, 114 sequences of equine D-loop region were obtained from GenBank. Total DNA of the samples were extracted through salting out procedure and utilized as template for amplification and sequencing of the D-loop region of mtDNA. Sequence analysis of the 247-bp D-loop region of mtDNA in all samples revealed a total of 44 haplotypes with 39 polymorphic sites. Six haplogroups (A–F) were identified in the phylogenic tree drowned for these haplotypes and sequences from GenBank. Total nucleotide diversity was obtained with in the range of 0.028 ± 0.009 in Iranian native horses. Fixation index values, employing Kimura-2 parameter method ranged from -0.001 to 0.172. Analysis of Molecular Variance (AMOVA) identified that some of these populations, especially Sistani horses, bear a genetic similarity with other populations and also with sequences from the GenBank (P > 0.05). Arab and Turkman horse populations displayed non-significant difference (P > 0.05), which may reflect the uncontrolled crossing between these two breeds. Caspian and Kurd horse populations showed significant differences with other populations and sequences from the GenBank (P > 0.05). The results of the current study indicate a high genetic diversity and as well as genetic similarity in some populations. According to the dateained results it is necessary to control the crosses between the animals populations and the production of progenies in Iranian native horses.

To evaluate the effects of different dry period lengths on milk yield, milk composition, reproductive performance and energy balance in dairy cows, 30 Holstein breeds (average 270 days pregnant) were made use of in a randomized complete block design. Cows were assigned to three treatments (60, 45 and 30 days of dry period) and two blocks as based on parity (either first lactation or multifarious cows). Milk production and composition as well as somatic cell counts of cows with 45 and 30 days of dry period were not significantly different from cows with 60 days of dry period (P>0.05). Body condition score changes after calving for 60, 45 and 30 days of dry period (1.06, 0.93 and 0.68, respectively) were significantly different. The smallest change in body condition score was observed for 30-day dry period ones, which also had a lower blood concentration of non-esterified fatty acids before calving (364.8 vs 394.9 and 390.9 µEq/l for 45- and 60-day dry periods). Mean days to first postpartum ovulation were 27.9, 27.8 and 22.7 days for dry periods of 60, 45 and 30 days, respectively (P<0.05). Fewer numbers of services per conception was recorded for 30- day dry periods compared with 45- and 60- day dry periods (1.5 vs 2.1 and 3.75, respectively). Cows with 30-day dry periods as experienced fewer number of days in negative energy state in comparison with 60- and 45-day dry periods, which amounts to a better reproductive performance.

The aim of the current study was the screening the activity of 23 medicinal plants for decreasing the in Vitro ruminal methane production, as well to and assess sheep ruminal in vitro fermentation parameters. 57.3 mg of each medicinal plants along with 142.7 mg control diet were weighted in 120 ml wheatons in 4 replicates. The samples were incubated using ruminal fluid obtained from 3 castrated male Ghezel sheep with 61.8 kg of body weight and 4 years of age. After 24 h of incubation, total Gas Production (GP), methane production, ammonia content as well as Volatile Fatty Acids (VFA) were assessed. The obtained data were statistically analyzed using a completely randomized design. The results showed that GP from the incubation of Allium hertifolium, Tribulus terrestris L and Foetida ferula-assa increased in comparison with the control treatment (p<0.05). The molar proportion of methane in GP was decline by 20% in treatments containing Allium hertifolium, Elettaria cardamomum Maton, Thymus vulgaris, Nigella sativa, Rosmarinus officinalis, Rheum palmatum, Chamaemelum nobile, Sygium aromaticum and Thea sinensis in comparison with the control treatment (p<0.05). The concentrations of total VFA in treatments containing Zingiber officinale, Nigella sativa, Chamaemelum nobile, Trachyspermum copticum and Thea sinensis were higher than that in control (p<0.05). On the other hand, treatments containing Allium hertifolium, Foetida ferula-assa, Alpinia officinarum, Elettaria cardamomum Maton, Achillea milhemsii, Glycyrrhiza glabra, Rosmarinus officinalis, Pimpinella anisum, Chamaemelum nobile, Hyssopus officinalis and Fumaria officinalis Lan contained lower levels of ammonia concentrations than in the control diet (p<0.05). The results indicated that the treatment containing Allium hertifolium lowered the methane production and ammonia concentration without any negative effect observed on the total gas production.

A study was conducted to determine the effects of diet formulation on Arian broiler breeder performance in their 50 to 64 wks of age. One hundred and sixty eight female and 24 male breeders were employed in 8 treatments of 3 replicates (7 females plus a male) in a completely randomized design (a factorial experience of 2 × 2 × 2). Eight experimental diets were formulated based on three factors, the first factor including, two levels of Apparent and True Metabolisable Energy corrected for nitrogen (AMEn and TMEn), the second factor being:, two levels of Total Amino Acids (TAAF) and Digestible (DAAF) of Feed, The third factor was included two levels of broiler breeder hens Requirements as based on Total Amino Acids (TAAR) and Digestible ones (DAAR). The results indicated that egg weight was significant difference on the main effects of energy and the main effects of amino acids of feed and requirements no significant (p<0.05). Treatment No. 3 (AMEn + DAAF + TAAR) was at the best level significantly in egg weight, 68.97 (g), egg production, 62.45, egg mass, 43.1 (g/hen/day) and feed conversion ratio 3.59 and treatment No. 7 (TMEn + DAAF + TAAR) was the worst level significantly in egg weight 66.51 (g), egg production, 48.21, egg mass, 31.99 (g/hen/day) and feed conversion rate 5.07. Percentage of eggs can incubate and hatchability was significant in the main effects of energy, amino acids of feed and requirements and fertility was significant in the main effects of energy and amino acids of feed, number of chicks per hen was significant in the main effect of energy and amino acid requirements (p<0.05). Percentage of eggs can incubate was in treatment No. 5 (TMEn + TAAF + TAAR), 99.48 %, fertility was in treatment No. 4 (AMEn + DAAF + DAAR), 91.87 %, hatchability was in treatment No. 2 (AMEn + TAAF + DAAR), 78.37% and the number of chickens obtained from any hens during the experimental period (50 to 64 weeks), was in treatment No. 6 (TMEn + TAAF + DAAR), 37.83 chicks, at the highest significantly level compared to Duncan multiple range test (p<0.05). This experiment showed that the type of diet formulation had significant effects on broiler breeder performance.

To evaluate the effects of wheat processing and dietary lipid sources on feedlot performance, carcass characteristics and fatty acids profile in meat of fattening calves, a number of 28 Holstein male calves averaging in weight of 296±56kg were randomly allotted in four treatments (7 steers each). The Study was conducted in a 2 × 2 factorial arrangement (two methods of wheat processing: steam flake and treatment with formaldehyde and lipid source; Roasted Soybean (RSB) and Rumifat). The experiment followed a completely randomized design. The study lasted for 98 ds (14d adaption). Dry Mater Intake (DMI) and Average Daily Gain (ADG) of calves were respectively evaluated daily and monthly. Following the final weighing at 85d, and in order to measure the traits related to carcass characteristics, three steers per treatment were slaughtered. No significant differences were detected for DMI, ADG and feed efficiency. Carcass traits were not affected by dietary treatments. The levels of C18:2, C18:3, C24:0 and polyunsaturated fatty acids (PUFA) were greater (P < 0.01) in steaks from steers fed RSB. RSB consumption resulted in increases the levels of C18:0 and conjugated linoleic acid (CLA) in steaks (P < 0.02). In contrast, amount of C:16 and Saturated Fatty Acid (SFA) were greater (P < 0.01 and P<0.05, respectively) in steaks from steers fed Rumifat. There was no effect of diets observed on the levels of other fatty acids. It was finally concluded that no difference was detected in the performance of steers through methods of wheat processing and lipid source, but the use of RSB in the diet improved the fatty acid profile of meat as regards human health.

In order to survey the inclusion effects of different levels of barley and/or corn grain in diet on growth and performance of Holstein calves 40 newborn calves were taken in 5 experimental groups with 4 female and 4 male calves in each group for a duration of105 days. The experimental group was comprised of: group 1; no barley (only consisting of corn grain) and other experimental groups 2, 3, 4 and 5 which contained 5, 10, 15 and 20 percent respectively of barley grain in total diet. The values of dry matter intake (DMI), body weight changes and feed efficiency ratio were evaluated periodically. The obtained data were statistically analyzed using repeated measurements of mixed procedures. The least square means of final weight, gain, total DMI and feed conversion ratio of calves, fed diets with no barley grain, were respectively, 138.5, 97.3 and 125.3 kg and 1.29. Increasing barley grain ratio in the diet resulted in reduction of DMI (P<0.05). Body weights in calves which consumed diets containing barley were lower as compared with the control (P<0.05), but there were no differences observed between the groups consuming diets containing barley. Increasing the barley content in the diets had no effect on feed efficiency ratio. DMI was improved with increasing calves age (P<0.05), but was not affected by the sex. Body weight, weight gain during the period as well as feed conversion ratio in male calves was more pronounced than those in females. All in all, replacement of barley up to 20 percent in Holstein calves, diets is possible with no arisal of any negative effect on their feed efficiency ratios.

The present research was conducted to estimate the dietary lysine (Lys) requirements of growing quails as based on performance and carcass constituents parameters at 3 to 24 d of age. The experiment was carried out in a complete randomized design arrangement the 6 dietary Lys levels; 1, 1.15, 1.30 (NRC 1994), 1.45, 1.60, and 1.75 %, from 3 to 24 d of age. A dose-response diet mainly based on corn, corn gluten and soybean meal was used. Lys content was minimized in dose-response diet (1%) while assuring the minimum levels of all other essential amino acids in a manner that would meet or exceed NRC (1994) recommendation. Each treatment consisted of 5 floor pens as replicate with 50 quail chicks. Second order equation methods were utilized for determining the optimum dietary Lys levels. With increase in dietary Lys, body weight, body weight gain and feed conversion ratio improved significantly (P < 0.05). In female Japanese quail, carcass and breast weights were significantly (P < 0.05) affected by dietary Lys. While dietary Lys has no significant effect on thigh weight, carcass and breast yields in female quails (P > 0.05), in male quails, Carcass, breast, thigh weights as well as yields are significantly affected by Lys level, during the birds 3-24 d of age (P < 0.05). Lys needs based on second order equation method when mixed performance parameters taken as response of Lys requirement were recorded as 1.48% at 3-24 d of age. The data suggested that total Lys requirement could be estimated based on second order equation method as 1.48, 1.54% respectively for female and male quails when carcass constitutents are considered at the birds 24 d of age. These results indicate that the NRC (1994) Lys requirement of Lys 1.30% (total basis) is not adequate from the birds 3 to 24 d of age for optimum performance in the case of Japanese quails.

For treatment of Anti-Nutritional Factors(ANFs), (β-N-oxalyl -L- α, β -diaminopropionic acid (β-ODAP) and Condensed Tannin (CT)) in grass pea, some such alkali treatments as NaOH, NaHCO3, KMnO4 and wood ash, besides water soaking and polyethylene glycol (PEG) (6000 MW) were employed. Metabolizable Energy (ME) of treated and of untreated grass pea was assessed using gas production technique, two-stage in vitro digestibility technique as well as chemical composition determination. merely NaOH treatment significantly increased ME in two step digestibility method. In ME calculation that using gas production, the ME content of grass pea was 8.52 (MJ/Kg DM), while water soaking and PEG revealed the highest levels of, 11.48 and 10.96 (MJ/Kg DM), respectively. There were negative significant correlations observed between β-ODAP concentration and both OMD (-0.47) as well as DOMD (-0.48). There was no negative effect of CT content of grass pea on dry matter digestibility (correlation 0.55). As regards high crude protein content, percent of β-ODAP reduction and ME content, either one of NaOH or water soaking treatments are recommended as the most suitable treatments as regards grass pea.

A genome consisted of 1000 biallelic single nucleotide polymorphisems (SNPs) on one chromosome with 100 CM length was simulated and different QTL variance distributions (Uniform, Normal and Gamma) and various numbers of QTL (5, 10 and 20) were considered as simulation assumptions and consecutively 9 various traits were generated. The comparison between GEBVs obtained from BayesC and GBLUP showed that GEBVs and true breeding values were largely correlated (r > 0.80) in training population for all traits. Comparing accuracies of GEBVs showed that both BayesC and GBLUP methods performed similarly, except in traits with 5 QTLs BayesC performed significantly better (P < 0.05). The accuracies of estimations using BayesC indicated that this method performed better under scenarios with low number of QTL and gamma variance distribution in trait of interest. However, GBLUP presented accurate estimations in all traits; and number of QTL and QTL variance distributions had no impact on accuracies of GBLUP estimations. These results can be due to assumed genetics model in trait of interest in each method.

The aim followed in the present study was to investigate the economic aspects of, and to derive Economic Weights (EWs) for Mature Body Weight (MBW) as well as for age at First Calving (AFC) in Holstein dairy cattle of Iran. Economic values (EVs) for traits were estimated using trait-by-trait bio-economic models. Absolute EVs were RLs -16400 and -17900 per cow per year for MBW and AFC, respectively. Because of the negative effects of these traits on profitability, EWs of -7540 for MBW and -3760 for AFC are suggested for a national selection index. A one day increase in AFC increased production costs by Rls 39600 per cow per year. Sensitivity analysis revealed that the EV for MBW was more sensitive to changes in live weight price than to feed costs. Results obtained in this study can be used in the development of breeding objectives and in the cost- benefit analysis of management programs which aim at changing the attitudes of farmers and of their consultants towards decreasing costs and therefore increasing profitability.

To study the effects of environmental factors on milk and fat yields (240day) traits of Iranian buffaloes, 22596 and 22165 records were utilized for milk and fat yield traits, respectively. Uni and bivariate analysis for estimation of (co)variation components of the traits were done in five lactations. Milk yield in the 1st lactation had the highest number of records (4482), collected through Center of Animal Breeding during 1986 2009. Estimation of genetic trends for both traits in the 1st lactation was also done. All factors except age at calving and season of calving exerted significant effects (p<0.01) on mile yield. Also all factors except age at calving significantly affected fat yield (p<0.01). High additive genetic variation was observed in this population and resulted in high heritability for either of the traits. Average heritability obtained from single and double trait genetic analyses for milk yield at five lactations were 0.49, 0.41, 0.54, 0.47 and 0.35 while for fat yield they amounted to 0.45, 0.36, 0.55, 0.40 and 0.50, respectively. Genetic correlations of milk yield in different lactations were higher than those for fat yield in different lactations. Genetic correlations among milk and fat yields in different lactations were high and positive.

In this trial, the effect of different levels of Echum amoneum (EA) (0.3, 30, 300 or 3000 µl) on in vitro ruminal fermentation characteristics and methane production was assessed. The parameters studied were in vitro Gas Production (IVGP), methane production, ammonia (NH3-N) concentration, in vitro Organic Matter Degradability (IVOMDe), Partitioning Factor (PF) (the ratio of substrate truly degraded to gas volume produced at 24 h of incubation) and total Volatile Fatty Acids (VFAs) concentration. The correlation of methane gas with total protozoa population and three subfamilies of Entodiniinae, Ophryscolecinae, Diplodiniinae and family of Isotrichdae, also, were studied. Gas production from insoluble fraction (b) (linear effect; P<0.01) was significantly (quadratic effect; P<0.01) increased with increasing level of EA. The inclusion of EA at either 300 or 3000µl increased IVGP at hours 24 and 54 (linear effect; P<0.01). However, methane production was reduced (linear effect; P<0.05) by 54, 41 or 43% when EA was added at 3, 30 or 300 µl respectively, without changing the degradability of organic matter. The inclusion of EA extract reduced NH3-N concentration (P<0.01), while PF (quadratic effect; P<0.01) led to an increase. On the other hand, EA addition decreased the concentration of VFAs and acetic acid (P<0.05), but increased the propionic acid (P<0.05). Moreover, the inclusion of EA has shown a significant effect of antiprotozoal activity, and, there is a tendency of total protozoa population, Diplodiniinae, Ophryscolecinae, and Isotrichdae family to decline. The results finally suggest that EA plant is of the potential to positively manipulate in vitro ruminal fermentation.