IRANIAN JOURNAL OF APPLIED ANIMAL SCIENCE
Year:2014 | Volume:4 | Issue:2|Papers Count:30

The objective of this review is to explore the current developments on major genes working on prolific sheep breeds and the mechanism behind it, while identifying the future working points. Productivity is the ultimate goal of farm animal production and prolificacy is a key feature in determining productivity in farm animals. Ovulation rate in mammals is an intricate process involving genetics and endocrine pathways. Exceptional reproductive capabilities along with higher ovulation rates were observed in many breeds of sheep from different parts of the world since the discovery of Booroola Merino sheep. These naturally occurring mutations acting on prolificacy are found in chromosomes 5, 6, 11 and X but speculations are around about the presence of more mutations on these genes or different genes on multi ovulating sheep breeds. The exact control mechanism of multiple ovulations and multiple births in prolific sheep breeds is poorly understood. Over the years it has been repeatedly shown that gonadotropins and intra ovarian factors play vital and variety of roles. More specifically, follicular stimulating hormone regulation during folliculogenesis could be a promise for the future studies. Among those intra ovarian factors, bone morphogenic protein system is one of the indispensable components, which exerts enormous enthusiasm among the scientific community towards manipulating ovarian folliculogenesis. Rather surprisingly, biological and physiological roles of bone morphogenic protein subfamily are not thoroughly elucidated and contradictory findings among the mammals make further twists, which will be the gaps to be filled in the near future. Presence of a regulatory control loop between oocyte, granulosa and theca cells through transforming growth factor B (TGFB) superfamily is proposed here.

Reactive oxygen species (ROS) plays an important role in sperm motility. The physiological generation at low concentration induces beneficial effects on sperm functions and plays a significant role in sperm metabolism. Meanwhile, the excessive generation of reactive oxygen species can overwhelm protective mechanism and triggers changes in lipid and protein layers of sperm plasma membrane, which induces lipid damage, protein damage, DNA damage, motility impairment and alteration in capacitation and acrosome reaction. Reactive oxygen species (ROS) can be measured by variable biomarkers as melondialdehyde (MDA) concentration, individual free radicals, etc. The quantification of free radicals in livestock semen is also briefly reported.

This study was conducted to investigate the effect of biological treatment with Pleurotus florida fungi on chemical composition and rumen dry matter (DM) and organic matter (OM) degradability of wheat and barley straw. Wheat and barley straw were collected from Golestan province of Iran and after pasteurization mixed with fungi spawn (than 5% by weight). After 21 days samples were dried in oven (60oC) in order to stop fungi growth. Dry matter (DM) and organic matter (OM) degradation determined using nylon bag technique with two fistulated Dalagh rams and samples were incubated at zero to 96 hours in rumen. Fungi cultivation significantly decreased the amount of dry matter (DM), Neutral detergent fiber (NDF) and acid detergent fiber (ADF) in wheat and barley straw (P<0.01). Ash and crude protein (CP) content significantly increased with processing by fungi in treatments (P<0.01). Ether extract (EE) and acid detergent lignin (ADL) content did not differ by processing with fungi. The soluble fraction (a) and potential degradability (a+b) of dry matter (DM) increased (P<0.05) by processing with fungi in both straw. The insoluble but potentially degradable fraction (b) of dry matter (DM) degradability increased (P<0.05) by processing with fungi in wheat straw, but did not change in Barley straw. The and a + b fractions of organic matter (OM) degradability increased (P<0.01) by processing in both straw. The b fraction of organic matter (OM) degradability increased (P<0.01) by processing with fungi in wheat straw, but did not observed difference in Barley straw. Therefore, it has been concluded that the treating the wheat and barley straw with fungi improved the nutritive value in the present study.

The aim of this study was to evaluate the concentrations of reproductive hormones in blood plasma and in follicular fluids of different sized follicles during various stages of the estrous cycle in Holstein cattle. Jugular blood samples from 42 adult Holstein cattle were collected immediately after the slaughter. Antral fluids from small (4-5 mm), medium (6-9 mm) and large (10-20 mm) follicles were collected and the stages of estrous cycle were recorded. The gonadotropin and steroid concentrations in blood plasma and steroid levels in follicular fluid were measured. Estradiol-17-b concentrations in antral fluids of small follicles in early diestrous were significantly (P<0.05) higher than the concentration of that in the follicular fluids from small antral follicles in other stages of the estrous cycle. Concentrations of estradiol-17-b in follicular fluids from medium antral follicles in metestrous were significantly (P<0.05) higher than that of those in proestrous and estrous phase of the estrous cycle. There were no significant differences in the follicular fluid concentrations of estradiol-17-b from the large follicles among the various stages of estrous cycle (P>0.05). The variation in progesterone concentration within the follicles of various size during different phases of estrous cycle was not significant (P>0.05). The plasma concentrations of FSH, LH and estradiol-17-b in proestrous and estrous were higher than the other stages of the cycle (P<0.05). The plasma progesterone concentration in late diestrous was higher than in metestrous, proestrous and during estrous (P<0.05).

To investigate the effects of certain factors on the rate of retained placenta, 2844 calving records from 1288 Holstein cows in a herd were used. These cows calved during year period of 2001 to 2007. A generalized statistical linear model was applied to analyze the data. Logistic regression model was applied as the statistical model. In the model, fixed effects of year, season (warm or cold) and sex and birth type (single or twin) of calf and parity and gestation length of dam were included. In data file, retained placenta incidence was introduced as binary codes: zero for healthy cows and one for cows with retained placenta and probability of code one was analyzed. Incidence of retained placenta was significantly affected by all the fixed effects included in the model. Odds ratio estimation for cold season compared to warm seasons was 0.619, which means probability of occurrence of this disease in cold season, is 39% less than in the warm season. Odds ratio estimation for female calves in comparison to male calves was 0.6, which implies that the former are 40% less probable to cause retained placenta. Probability of this disease in twin calving was 5.9 times more than singles. By increasing the parity number of the dam, the probability of experiencing retained placenta in cow increased. It could be concluded that the incidence of retained placenta may be reduced by management modifications.

The present study was aimed to examine the association of bovine follicular stimulating hormone gene polymorphism with sperm quality traits including sperm volume (SV), sperm concentration (SPCO), total sperm (TS), fresh sperm motility (FSM), total fresh motile sperm (TFMS), post thaw sperm motility (PTSM), total post thaw motile sperm (TPTMS), number of produced payout (NPP), number of fresh motile sperm in each milt ejaculation (NFMSE), motility before and after the freezing (MBATF) and number of post thaw motile sperm in each milt ejaculation (NPTMSE). We used polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) in 83 bulls belonging to two progeny test center. The frequency of the A (PSTI+) and B (PSTI-) alleles were 0.675 and 0.325, respectively. The genotype frequency for AA and AB were 0.35 and 0.65, respectively. The BB genotype was omitted for analysis. Mixed and probity models analyses of sperm quality traits considering genotype and environment as fixed effects and animal as a random effect suggested that sire was a significant source of variation (P<0.001) in all traits. The AB genotype resulted in a significant increase in TS (P<0.0425), NPP (P<0.0302) traits greater than AA genotype. However, AA genotype had significant effect on PTSM (P<0.0001). But not on sperm volume (SV) (P=0.1749), sperm concentration (SPCO) (P=0.1423), fresh sperm motility (FSM) (P=0.5327), number of post thaw motile sperm in each milt ejaculation (NPTMSE) (P=0.5249), total post thaw motile sperm (TPTMS) (P=0.3982), total fresh motile sperm (TFMS) (P=0.2667), total post thaw motile sperm (TPTMS) (P=0.5898) and motility before and after the freezing (MBATF) (P=0.1785). These results indicate that new molecular markers associated with sperm quality traits can be used in markerassisted selectioninbulls.

More than 80% of the total milk protein contains caseins that are to forms a-s1, a-s2, b-casein and kappa casein. Kappa casein is smaller than other milk proteins but due to have a role in size and stability of micelles. The present study describes polymorphism of kappa casein gene. This is the first study of kappa casein gene polymorphism in Najdi cattle of Iran. We used the polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) technique to screen DNA polymorphism in cattle. We amplified the 453 fragment consisting on part of exon 4. The amplified fragment was digested with HinfI restriction endonuclease and subjected to electrophoretic separation in 3% agarose gel. Two alleles were observed, A and B. It gives frequencies of 0.54 and 0.46 for A and B alleles. Also, genotypes AA, AB and BB with frequencies of 35%, 37.5% and 27.5% of the total study population were diagnosed. Existence of HardyWeinberg equilibrium indicated that there was not any choice in order to increase or decrease the frequency of genotypes in the kappacasein population in this herd. Also, in this population kappacasein gene has medium level of heterozygosity.

The present study was conducted to evaluate the effect of parenteral supplementation of cobalt, copper and iron in late pregnancy on ewe hematology parameters and lamb vigour. Twenty ewes were allocated to one of two groups (n=10). In the test group, on day 120 of pregnancy, cobalt, copper and iron were injected at a dose of 0.1 mL/kg BW (Fercobsang, France, cobalt gluconate 5 mg/100 mL, copper gluconate 0.5 mg/100 mL and ferrous citrate 1000 mg/100 mL). Ewes in the control group received equal amounts of normal saline as placebo. Group had no significant effect on ewe hematological parameters (P>0.05). There were no significant effects of parenteral mineral supplementation on lamb birth weight, rectal temperature and weaning weight after birth. Lamb viabilities are reported as scores as these gave a true representation of the effects of treatment on underlying measurements. However, there were no differences between groups in lamb vigour and sucking assistance score. It seems that using of additional trace elements in late pregnancy could be effective only in deficiency situations.

This study was conducted to evaluate the possibility of alfalfa replacement with fenugreek hay for ruminants, using in vitro gas production parameters and some of rumen fermentation characteristics. For this propose, five different total mixed rations were formulated to meet nutrient requirements of 35 kg growing lambs with gradually replacement of alfalfa in control diet (T1) with different levels of fenugreek hay (25, 50, 75 and 100%, respectively T 2, T3, T4 and T5). In vitro gas production (mL/200 mg DM) was determined at 2, 4, 6, 8, 12, 24, 48, 72 and 96 hours of incubation. AmmoniaN concentration (mg/dL) and pH of rumen liquor was determined immediately after removal. Gas production was increased with increasing levels of fenugreek (P<0.05). Significant increases of gas production from insoluble fraction (b) were observed with increasing levels of fenugreek hay (P<0.05). A same trend was observed for potential gas production (a+b, P<0.05). Also, the constant rate of gas production (c) of T2, T3 and T4 were significantly higher than control, but the differences between T3, T4 and T5 were not significant. Replacement of fenugreek at 25 and 75 percent significantly increased final pH compared to control (100% alfalfa) (P<0.05), but the differences between T3, T5 and control and between T3, T4 and T5 were not significant. Short chain fatty acids production (mmol/200 mg DM) was significantly greater in treatments with 50% or more fenugreek substitution (P<0.05). Organic matter digestibility of treatments containing 50% or more fenugreek hay (T3, T4 and T5) were significantly higher than control (P<0.05). Similarly, estimated metabolisable energy content of these treatments were higher than control (P<0.05). According to these results, it can be concluded that fenugreek can provide highly valuable forage for ruminants with comparable feeding values with alfalfa, and alfalfa can be replaced completely in ration with fenugreek hay without any problem.

The present study was aimed to improve the reproductive performance of Corriedale ewes by nutritional flushing. Forty Corriedale ewes were divided into four treatment groups (TC, T1, T2 and T3) with 10 ewes in each group (n=10). At the beginning of the breeding season extra feeding (flushing regime) was started for approximately 34 days such that two estrus cycles were covered. First group i.e. TC (control) received no concentrate supplement, only grazing for 6-8 h was practiced. The treatment groups were fed concentrate supplement of 300 g/ewe/d (T1), 400 g/ewe/d (T2) and 500 g/ewe/d (T3) for 34 days in addition to grazing for 6-8 h. Changes in body weight were significantly (P£0.05) higher in the ewes fed 500 g concentrate than TC and T1 while no significant difference was found between the other groups in respect of the body weight gain of the ewes. T2 and T3 groups revealed significantly (P£0.05) higher body condition score than that of control and between T2 and T3 groups than that of T1 group, however no significant difference between Control and T1 groups as well as between T2 and T3 groups were observed, respectively. The tupping percentage recorded in the ewes of all the four groups was 100% and the lambing percentage observed was found to be 70%, 80%, 90% and 100% in TC, T1, T2 and T3 groups, respectively. An increase (P£0.05) was observed in the birth weight of lambs with highest average weight observed in T3 group followed by T2 group, T1 group ewes and control. The study revealed that the body weight of ewes, dam performance during their gestation period, lambing rate and birth weight of lambs of Corriedale ewes showed considerable improvement due to nutritional flushing. The study also indicated that among all four treatment groups, T3 showed significant improvement in body weight and reproductive efficiency as a result of flushing supplementation during mating season. Hence it was concluded that feeding 500 g of concentrate in addition to sufficient grazing is ideal feeding regimen as compared to other treatment groups in order to achieve a higher body condition score and reproductive performance.

A pedigree file consisting of 5860 individuals, 167 sires and 1582 dams collected at Makooei sheep breeding station (MSBS) during a period of 24 years (1990 to 2013) was used to calculate the inbreeding coefficients to reveal any probable effects of inbreeding (F) on the studied traits. The studied traits were classified to the five main groups including body weight, Kleiber ratio, body measurements, greasy fleece weight and reproductive traits. The inbreeding coefficient among the individuals ranged from 0 to 25% with an average of 0.33%, and ranged from 0 to 25% among the ewes with an average of 0.21%. Fluctuations in individual and maternal inbreeding were observed in the period under study. The average generation interval was calculated as 3.6 years. The effective population size of the flock was 51.8 animals. The rate of inbreeding was 0.08% per year and 0.53% per generation. Six different models were applied and likelihood ratio test (LRT) was used to select the appropriate model. Based on the LRT, model II was selected as appropriate model for growth, greasy fleece weight at 6 months of age and kleiber ratio traits. The traits related to the live body weight were affected negatively (P<0.001) by the quadratic individual F. The linear individual regression coefficient of the Kleiber ratio was estimated significantly (P<0.01) as 0.001, as well the linear maternal inbreeding regression was estimated significantly (P<0.05) as 0.0002. In general, body measurements were affected negatively by the quadratic effects of inbreeding (both individual and maternal) and positively by the linear effects of inbreeding. The reproductive traits were studied based on ewe inbreeding coefficient. Among the reproductive traits, the quadratic regression coefficient of conception rate was estimated significantly (P<0.05) as -0.22. Quadratic regression coefficient of litter mean weight per lamb born were estimated significantly (P<0.01) as -0.63 per 0.01 change in the ewe inbreeding coefficient. Therefore, inbreeding should be avoided, except for purposes of genetic breeding whose main objective is the fixation of certain alleles in the population.

Ten male Merghoz goats with initial live weights of 29.2±1.2 kg (Mean±SE) were used to investigate the effect of natural changes in photoperiod on dry matter intake (DMI) and reproductive activity during a 365 day study. The bucks were housed in individual pens, under natural daylength condition at west of Iran, Kermanshah (34o18’ N and 47o 3’ E and 1420 m above sea level). A diet was offered with an estimated concentration of metabolizable energy and crude protein of 7.9 MJ and 98.8 g per kg dry matter (DM) respectively. Live weight, DMI, and additive daily gain (ADG) of individual animals were recorded weekly. The serum testosterone concentrations were determined in blood samples collected at monthly intervals. During the observation period, semen was collected monthly with the aid of an electro-ejaculator and examined microscopically immediately after collection. The physical parameters of semen and the semen index were recorded. The sexual behavior and testicular size of goats were assessed monthly throughout the study period. The highest DMI was observed during summer (64.3±0.9 g/kg BW0.75) and spring (62.2±2.9 g/kg BW0.75) however, the lowest was recorded in the winter season (54.0±0.9 g/kg BW0.75). The seasonal values of ADG (g/d) ranked spring > summer > winter > autumn. Bucks demonstrated the highest sexual behavior in late summer and, thereafter during autumn, using the lower (P<0.05) number of mounts per ejaculation and a higher frequency (P<0.05) to sniff, approach, and vocalize a doe with estrous status. This was coin-cided with a higher (P<0.05) level of plasma testosterone (8-10.1 ng/mL) and the best semen quality (semen index: 744-989×106/mL) and quantity (semen volume: 1.1-1.2 mL per ejaculate), higher testis length (13.3-14.7 cm) and width (6.0-6.1 cm) and scrotal circumference (32.2-35.5 cm). It is concluded that, in Merghoz bucks, the seasonal pattern of DMI and reproductive activity may be attributed to each other as well as pho-toperiod.

This study was undertaken to compare the efficiency of fresh and frozen-thawed buck semen on in vitro fertilization (IVF) of goat oocytes. Cumulus oocytes complexes (COCs) were collected by aspiration of 2-6 mm diameter follicles, which were obtained from slaughterhouse. Upon grading, only normal quality COCs were maturated in TCM-199 for 48 hours. The percentage of COCs reached to the M-II stage was 61.41±1.97%. The matured COCs were fertilized for 5 hours in Brackett and Oliphant media using fresh and frozen thawed semen separately. After fertilization the oocytes were cultured in TCM-199 for 48 hours to observe the cleavage rate. The maturation, fertilization and culture were performed in an incubator at 38.5oC with 5% CO2 in humidified air. After fertilization cleavage rates were observed to check the fitness of zygotes to be morula and blastocyst. It was observed that the rates of normal fertilization (2 PN formations) for fresh and frozen semen were 36.02±2.79 and 34.73±2.58%, respectively and the cleavage rates were 25.19±2.5 and 21.01±2.8%, respectively. No significant differences (P>0.05) was observed between fresh and frozen semen in the efficiency of in vitro fertilization and subsequent development of goat embryos. It can be concluded that, both fresh and frozen semen can be used for IVF and subsequent development of goat embryos.

The diacylglycerol acyltransferase 1 gene (DGAT1) was identified as a strong candidate gene affecting mutton quality traits in sheep. Single nucleotide polymorphism creates a single base mutation (C to T) in AGCT site of endonuclease AluI. DGAT1 is one of the candidate genes to improve carcass characteristics in feedlot animals. In order to study area T487C in exon 17 of the DGAT1 polymorphism, Iranian Moghani sheep breeds randomly slaughtered in the abattoir were recorded. DNA was extracted from 150 samples of Moghani sheep. Polymerase chain reaction to amplify 309 bp of exon 17 DGAT1 gene using a pair of specific primers was performed. Genotypes obtained from method PCR-RFLP and directly from agarose gel. Two alleles T and C with frequencies of 0.829 and 0.171 were observed respectively. Statistical analysis showed polymorphism in exon 17 region of the gene significantly correlated with carcass weight and dressing percentage (P<0.05). So that the CC genotypes of the significant mean carcass weight and dressing percentage heavier than had TT genotypes (P<0.05). Of polymorphism can be observed that improvement in breeding programs to improve carcass weight and dressing percentage through selection in favor of superior genotypes be used.

This study was undertaken to investigate the effect of sabara leaf meal on body weight, testicular traits and linear body measurements. Live body and testicular measurements (body weight, height at withers, body length, heart girth, testicular circumference and testicular length were monitored on Red Sokoto bucks). Bucks were managed in a complete randomized design with 4 treatments and replicates. The sabara leaf meal (SLM) was fed at concentration of 0, 10, 20 and 30% in treatments 1, 2, 3 and 4 respectively. Bucks fed diets with 10-30% SLM gained weight (P<0.05) better than those fed the control diets. The body length, height at withers and testicular circumference all increased with level of SLM in the diets with bucks on 20% SLM being heavier, however heart girth and testicular length were not affected by the dietary treatments. All phenotypic correlations between body and testicular measurements were positive and significant (P<0.01). The highest correlation coefficient was found between testicular circumference and body weight. It could be concluded that SLM inclusion from 20-30% level gave high growth performance in terms of body and testicular measurements without any adverse effect on performance. More research is therefore needed to examine the fertility of bucks fed sabara leaf meal.

This study was initiated to characterize urban and peri-urban sheep production systems and their economic importance in and around the towns of Debre Berhan and Dessie, Ethiopia. The study was undertaken using group discussions, structured questionnaire and personal observations. In both locations the majority of sheep producers were male household heads and predominantly traders in urban and farmers in periurban areas. The average family size was more in Debre Berhan periurban (5.4) area than Dessie periurban (4.8). In Debre Berhan periurban areas, 39.3% had a land hold size between 1 and 2 ha and in Dessie peri-urban areas 48.4% respondents had a land hold size of<0.5 ha. The number of sheep and other livestock population was higher in Debre Berhan periurban than Dessie periurban area. Except brewery dried grain all other types of feed used for sheep production were similar but the availability was different among the study areas. In both urban and periurban areas major available feed types were natural pasture grazing, hay, crop residues, wheat bran and oil seed cakes, by-products from local breweries and legume grains processing. Sheep rearing constitutes the first source of income in Dessie area and the second source of income in Debre Berhan area. Urban and peri-urban sheep production has economic advantages as sources of in-come and food to the household. High feed cost, lack of improved breed, capital and labor shortages were major constraints. Conducive weather conditions, attractive market price, and availabilities of supplementary feed found in urban areas were considered as beneficial for sheep production. Although, there are constraints for sheep production, available opportunities are to encourage engaging in sheep production. Scientifically proven and efficient feeding packages from locally common available feed resources are required.

Generally, only a fraction of the mineral ingested by an animal is effectively absorbed, while most are bound to other components such as fibre and then excreted. In this study, faecal mineral composition differ-entials were used as indicators of mineral uptake by pullets supplemented varying levels of plantain ash in their daily rations for nine weeks. Plantain stalk and root base samples were collected, sun dried and ashed to produce plantain stalk ash (PSA) and root base ash (PRA), respectively. Ninety six (96) day old Isa Brown pullets were reared to 15 weeks of age and thereafter divided into 2 major groups of 48 birds each. Each group was divided into 4 subgroups of 12 birds each and each subgroup divided into three replicates giving four birds per replicate in a completely randomized design. The PSA and PRA were fed to the pul-lets as mineral supplements to commercial grower from the 15th to 18th week (4 wk) and layer mashes from the 19th to 24th week (6 wk) at the rate 0, 1, 2 and 3 g per kg body weight so that one group received PSA and the other PRA. In each case, the zero supplementation served as control. At the 9th week of feeding, faecal samples were collected from the groups, dried in the sun and analyzed for their mineral compositions by atomic absorption spectrophotometry. Among the macro minerals, both PSA and PRA supplementation resulted in reductions in the faecal concentrations of K and Mg, with increasing supplementation level, re-sulting in further reduction of faecal content of these minerals. Mg showed highly significant (P<0.05, P<0.01) regression effects for PSA and PRA, respectively. Reductions in faecal Ni and Fe concentrations were high (47.62 and 79.19%) across 1 g/kg body weight (BW) PSA and PRA supplementations, while it was 83.33% for Mn at the same 1 g/kg BW PRA supplementation. Ni (PSA) and Cr (PSA and PRA) values were significant (P<0.10) for regression effects, implying that the faecal values of these minerals could be predicted from any given quantity of plantain ash using the regression equations. PRA supplementations resulted in increasing faecal content of the two heavy metals, that is, lead and cadmium, indicating selective poor intestinal absorption of these. Plantain ash could serve as potential sources of absorbable mineral supplements and also could improve mineral uptake from commercial diets offered to pullets.

The aim of the present study was to assess whether near infrared reflectance spectroscopy (NIRS) and re-gression equations are the practical and accurate approach of nutritional assessment of common feedstuffs. Therefore two experiments were conducted to study the effect of amino acid determination methods on broiler performance. In experiment I, two hundred thirty four male Ross broiler chicks were fed a commer-cial starter diet from d 1 to 16 of age followed by the test diets from d 17 to 21 to determine the digestible amino acids content of wheat, corn and soybean meal. The 3 test diets consisted of corn, wheat or soybean meal was used as the sole sources of protein. On d 21, birds were killed and ileal digesta were collected for determining standardized ileal amino acid digestibility (SID). The in vivo values of SID were compared with values predicted by NIRS and regression methods. Experiment II was conducted to compare the effect of feed formulation based on SID determined by in vivo with regression and NIRS prediction methods on broiler performance. The results showed that the SID contents of wheat and corn predicted by NIRS and regression method were close to in vivo values. Values predicted by NIRS and regression for soybean meal varied when compared with those of in vivo assay. Although, these differences were not appeared when comparing performance of broiler fed diets formulated based on SID values estimated through in vivo trial, NIRS and regression methods. This study reveals that feed formulation based on digestible amino acids estimated by NIRS and regression methods are reliable for feed formulation in commercial poultry production.

The objective of this paper was to study the responses on productive performance, carcass characteristics and plasma constituents of modern broiler chicks to administration of cinnamon powder (CP) in the diet. Commercial breeds (Ross 308) of broiler chicks examined from 1 to 42 days of age. This experiment was conducted as a completely randomized design with 5 treatments and four replicates (15 chickens per pen) involving: 1) control diet (basal diet); 2) basic diet plus CP 0.25%; 3) basic diet plus CP 0.50%; 4) basic diet plus CP 0.75% and 5) basic diet plus CP 1.0%. The addiction of CP to the diets of broiler chicks had no significant effects (P>0.05) on cholesterol, triglyceride, low density lipoproteins (LDL), abdominal fat, gizzard and heart weights and on breast protein percentage. However, the administration of CP had significant effects (P<0.05) on final body weight, body weight gain, feed intake, feed conversion ratio (FCR), liver weight, glucose level, thiobarbituric acid (TBA) and breast fat percentage of broiler chicks. The highest (P<0.05) FCR and body weight gains were observed with diet 3 at the end of the experiment. In general, the addiction of CP to the diet of broiler chicks improved body weight and decreased the TBA, glucose, LDL and weight of some inner organs. Taking into account the results mentioned before, the use of CP can be proposed as an ingredient for broiler diets.

Two hundred and forty Hubbard Classic broiler chicks were used in a 35 day trial at Chittagong Veterinary and Animal Science University farm, Bangladesh to study the effects of supplemental choline chloride on performance parameters, carcass characteristics and their association in commercial broiler. All birds had free access to ad libitum feeding. Birds were fed four types of diet i.e. diet without choline chloride (T0), diet containing 0.1 g / 100 g choline chloride (T1), 0.2 g / 100 g choline chloride (T2) and 0.3 g/ 100 g choline chloride (T3). Results indicated that weight gain differed (P<0.05) at 5th week irrespective of the level of supplemental choline. Similar to weight gain, feed intake also differed (P<0.05) at 5th week. However, feed conversion ratio differed from the 3rd to the 5th weeks. Weight gain and feed intake were positively correlated and feed conversion ratio was negatively correlated with carcass parameters. It could therefore be inferred that increasing levels of supplemental choline may progressively improve weight gain, feed efficiency and carcass characteristics in commercial broiler.

In this experiment 180 Azerbaijan province native laying hens from 28 to 40 weeks were separated in 6 treatments and 3 replicates (10 birds per replicate) as a (2×3) factorial arrangement of treatments in a completely randomized design. Treatments included two levels of dried tomato pomace (DTP) (8 and 16%) and 3 types of using methods (unprocessed, alkali and acid processed). The results showed that different levels of DTP and processing methods significantly affected the performance, egg traits and blood parameters of native laying hens (P<0.05). Using 16% of DTP in contrary with 8%, without having any other adverse effects on feed conversion ratio and other production parameters, only reduced the eggs weight. In interaction between the levels of DTP and processing methods, alkali processing, improved the adverse effects of high level of DTP on eggs weight, while acid processing could not show this effect. DTP processing and levels, improved the egg yolk color index. Processing with acid increased the values of triglyceride and albumin in the hens' blood. In 16% of DTP, more than triglyceride and albumin, the level of total protein in contrary with 8% increased. Interaction between DTP and processing methods showed that with 16% of DTP in alkali treating, the values of triglyceride and albumin in blood reduce, while the total protein increased. In acid treating, the percentages of heterophile and heterophile to lymphocyte ratio reduced, while the lymphocyte percentage increased. The overall results showed that in native laying hens, using dried tomato pomace up to 16% of their diets, not only did not have any adverse effects on their performance, egg traits and blood parameters, but also increases some of them, that these beneficial effects improved by alkali and acid processing methods.

The effects of Trigonella foenum graecum (TF) and Foeniculum vulgare (FV) seeds powder on antimicro-bial activity and performance of broiler chickens were studied. Based on a completely randomized design, 240 broiler chicks (Ross 308) were assigned to 4 treatments and 4 replicates. The treatments were a basal diet (control, T 1), T 1 plus 0.5% TF (T 2), T 1 plus 0.5% FV (T 3) and TFFV (0.25% TF+0.25% FV) (T 4). The diets fed to birds during a 1-42 days period. Treatments containing medical plants showed better performance and lower total number of bacteria (TNB) and Coliform compared to the control (P<0.05). The presence of salmonella was negative in all tested samples. The weight and length of small intestine and carcass yield in birds fed medicinal plants were higher than those of control (P<0.05). Therefore, the results of this study showed that the use of medicinal plants can improve performance and health conditions in broiler chicks.

This experiment was conducted to evaluate the effects of different levels of Portulaca oleracea (PO), medicinal plant, on performance, egg traits, blood biochemical and immunity parameters of laying hens. One hundred eighty Hi-Line (W-36 strain) mature laying hens 65 up to 76 weeks of age were allotted in a completely randomized design consisting of 5 treatments and 3 replicates (12 birds per replicate). Treatment groups consisted of a control group (1) with no PO supplementation and experimental groups 2, 3, 4 and 5 which contained 0.5%, 1.0%, 1.5% and 2.0% of PO powder, respectively. Using different levels of PO significantly affected the performance, egg traits, blood biochemical and immunity parameters of laying hens (P<0.05). The highest values for egg weight, egg production percentage, egg mass, feed intake, feed conversion ratio, egg yolk color index, albumin percentage and blood high density lipoprotein (HDL) were obtained by feeding 2.0% of PO. The highest level of blood hemoglobin was observed by feeding 1.0% of PO. The overall results showed that feeding Portulaca oleracea powder up to 2.0% in the diet has a positive effect on mature laying hens performance and egg traits.

This experiment was undertaken to evaluate the effect of dietary level of artichoke (Cynara scolymus) on growth performance and immune response of broilers under heat stress (HS). Two hundred forty day-old broiler chicks (Ross, 308) were randomly assigned to one of four dietary treatments with four replicate pens per treatment (15 birds per pen) in a completely randomized design with a 2 × 4 factorial arrangement (4 treatment diets and 2 different temperatures rearing systems). Treatment diets were: 1) control diet, 2) and 3) control diet supplemented with 15 and 30 g artichoke, respectively and 4) control diet supplemented with 300 mg/kg vitamin E. Body weight (BW) and feed conversion ratio (FCR) were not influenced by dietary artichoke (P>0.05). In the case of sheep red blood cells (SRBC), there were no significant differences be-tween treatments. However, the control group in HS condition showed lower titer for sheep red blood cells (SRBC) while group receiving 3 percent artichoke showed higher titer (P<0.05). There was no significant difference between treatments for Newcastle antibody titer. Regarding lymphoid organs, the weights of bourse and spleen were similar, while liver weight differed between treatments. In this regard, chicks under HS in the control group had lower weight than the other groups. Lymphoid organ weights and antibody responses were significantly reduced under HS. These results indicated that HS severely reduced growth performance and immune response of broilers, whereas the immune response of broilers could be improved by dietary artichoke supplementation under HS.

The present study was carried out to examine the effect of supplemental dietary valine in the starter diet of broilers (0-15 d of age) on performance, antibody response to Newcastle disease virus vaccination and bone mineralization. The experiment was conducted using 300 Ross 308 male broilers. One-day-old chicks were randomly allotted to 3 groups; each group consisted of 5 replicate pens with 20 birds per pen. Chickens were fed one of three dietary treatments with varying concentrations of valine; the first diet was adequate in valine (0% valine), the second and third diets had an excess in valine (0.08% and 0.16% synthetic valine in diet) because valine was added in place of inert filler. The results showed that supplemental dietary valine did not alter either feed intake, body weight gain or feed conversion ratio. Hemagglutination Inhibition titre was significantly increased when valine was added to the diet (P<0.05). The supplemental dietary valine had a significant effect on the calcium concentration in bone (P<0.05), but there was no significant effect on the phosphorus concentration in bone.

This study was conducted to investigate the prediction of growth performance using linear regression and artificial neural network (ANN) in broiler chicken. Artificial neural networks (ANNs) are powerful tools for modeling systems in a wide range of applications. The ANN model with a back propagation algorithm successfully learned the relationship between the inputs of metabolizable energy (kcal/kg) and crude protein (g/kg) and outputs of feed intake, weight gain and feed conversion ratio variables. High R2 and T values for the ANN model in comparison to linear regression revealed that the artificial neural network (ANN) is an efficient method for growth performance prediction in the starter period for broiler chickens. This study also focused on expanding the experiment with more levels of inputs to predict outputs the using best ANN model.

The aim of this study was to isolate Escherichia coli from chickens and to determine the presence of the eaeA gene, a virulence factor detected in Escherichia coli, in the isolates by polymerase chain reaction (PCR). Different chicken organs (lung, liver and spleen) were inoculated onto blood agar and biochemical tests were performed on the suspicious isolates. Escherichia coli was isolated from 67.5% (81.120) of the samples. DNA was extracted from these isolates and was amplified by PCR, using a pair of primers derived from the eaeA (virulence) gene. In the agarose gel examination of PCR products, 48.1% (39.81) of the isolates were determined to have this virulence factor. Correct amplification with a molecular length of 384 bp was obtained in the analysis of all the isolates by species-specific PCR, which confirmed the results of the detection of the eaeA gene in Escherichia coli. The eaeA gene, which is mainly responsible for the virulence of Escherichia coli, is commonly present in Escherichia coli strains isolated from this region and the significance of this situation for animal and public health was discussed.

An experiment was conducted to study the effect of Epinephrine (EP) and bromocriptine (BR) on productive traits of laying hens. Thirty White Leghorn hens, 50 weeks old, were divided into three equal treatments (with 10 hens for each treatment): control, physiological serum (0.5 mL/hen/week), EP (0.5 mL/hen/week) and BR (100 g/kg of body weight (BW); w/v in absolute alcohol). Hens were injected once a week for 10 weeks. At the end of the experimental period, all hens were killed by decapitation. Ovaries, oviducts and ovarian follicles were examined. Ovary folliculogenesis was affected (P<0.01) by EP and BR treatments. There were larger yellow follicle (LYF), smaller yellow follicle (SYF) and larger white follicle in EP and BR treated hens compared to control group respectively. EP and BR treatments shortened total pause length compared to control (P<0.01). Mean weekly egg production was higher (P<0.01) for treated hens with BR and EP compared to control group. Percentage of weekly egg production was higher (P<0.01) in treated birds compared to control group. It can be concluded that EP and BR may promote ovarian follicular development and stimulate ovulation in laying hens at the end of their reproductive cycle.

Stearoyl-CoA desaturase (SCD) is a rate-limiting enzyme in the biosynthesis of monounsaturated fatty ac-ids (MUFA). A number of studies support the hypothesis that SCD gene regulation and polymorphism may affect fatty acid composition and fat quality in meat and milk. Single nucleotide polymorphisms in the cod-ing region of the bovine stearoyl-CoA desaturase gene have been predicted to result in p. 293A (alanine at amino acid 293) and p. 293V (valine at amino acid 293) alleles at the stearoyl-CoA desaturase1 locus. The objective of this study was to characterize polymorphisms of stearoyl-CoA desaturase 1 (SCD1) gene in Khuzestan buffalo population. This is the first study of SCD1 gene polymorphism in Iranian buffalo. The blood samples were taken from 85 buffalo of Khuzestan-Iran population. Genomic DNA was extracted using a kit DIAtom DNA prep. After this, PCR reactions were made by using primers that encloses exon V. A 400 bp fragment amplified with standard PCR method. The PCR products were digested by NCO1 restriction enzyme with PCR-RFLP method. All samples were genotyped on 3% agarose gels stained with ethidium bromide. Electrophoretic mobility shift determined that there were not genetic differences between these animals in the studied region by using NCOI enzyme. Also, this study showed that genotype frequencies were not in Hardy-Weinberg equilibrium for SCD1 gene.

The aim of this study was to evaluate the differences between cold carcass weights (CCW) for the Catalan Pyrenean horse (Cavall pirinenc català) breed according to different variables: area of origin, farm, gender and age. Linear regression models were applied using a generalized linear model (GLM) procedure for CCW of 397 animals (217 males and 180 females) slaughtered in a commercial abattoir. Fixed effects GLMs included age, gender, farm and area of origin, and their interactions. The best model for explaining CCW included area of origin only (borigin=0.02541, Wi=0.67, R2=0.0518) thus indicating that sex and farm were not important explanatory variables, as might have been expected. This information may be useful for obtaining better estimates of carcass weight of this breed for carcasses from specific breeding areas.