IRAQ JOURNAL OF AGRICULTURAL RESEARCH

This study was conducted in Futhaliya village, Baghdad province, during the summer and winter seasons, 2007 to study the influence of herd size, age at first calving, days open and season on daily milk yield of Iraqi buffaloes. Two hundreds buffalo owners owned 4-250 heads of different ages were randomly selected. The overall herd size ,milking herd size, age at first calving, days open ,as well as daily milk yield were recorded during winter and summer seasons . The overall and milking herds were divided into 6 groups according to their own size. Higher (p<0.01) daily milk yield was found in medium –sized herds (20-40 heads) as compared with small–sized herds (1-10 heads ), the average was ranged from 6.22 ±1.53 to 6.25± 1.01 kg. Daily milk yield was significantly (p<0.001) greater during winter (6.42 ± 2.06 kg) than summer (5.62 ± 1.61kg). The regression coefficient of daily milk yield was significantly higher (p<0.01) on age at first calving, whereas it lacked significance on days open. In conclusion, the medium–sized herds in this location were superior in daily milk yield as compared with small-sized herds during winter than summer seasons. The age at first calving had a significant effect on daily milk yield.

Twenty eight Frisian calves are divided into four groups, each group contain seven calves each, to study the effect of adding some nutritive antibiotic (Monensin, Salinomycin, and Lasalocid) to the salt block, on the frizian calves.
The study lasted for (120) days and the results declared a decrease in the values of the Acetic acid to be compared with the controlling group, yet it is an immaterial decrease. As for the values of the Acetic acid of the other three groups, the results indicated immaterial dissimilarities of about (p<0.01) to be compared with the controlling group. The highest value has been recorded in the fourth group (33.04) and the immaterial dissimilarities disappeared among the experimental groups.
The values of the butyric acid have demonstrated an absence in the immaterial dissimilarities among the three groups and the controlling group.
An immaterial decrease of about (p<0.01) happened in the values of the NH3 in the three groups to be compared with the controlling group. This is a natural result since this will lead to the decrease of the lost energy in the potbelly of the animal so that the pure energy of the diet will be increased.
All these activities will lead to a good growth as well as an improvement in the efficiency of using the forage. The test of the value of the PH has recorded an immaterial height of about (p<0.05) for the three groups to be compared with the controlling group.
As for the total product of the volatily fatty acid of the fourth group, in comparison to the controlling group, has an immaterial decrease of about (p> 0.01). An immaterial difference is observed between the second and the third groups of about (p> 0.05) to be compared with the controlling group.
Thus, we conclude that the nutritive antibiotic has an important role in the improvement of the Frisian calves' growth as well as an increase in the efficiency of its nutritive transformation. In addition to that, the three antibiotics share an equal efficiency in their effect.

Ststistical analysis were performed for 2046 total milk production records and for breeding and veterinarian records belonged to incidence of pneumonia in Holstein cattle and their calfs in AL-Nasar Dairy Cattle Station, United Company for Animal Resources in AL-Sewayra between 1998 to 2001.
Statistical model by SAS (2001) was used. Overall mean ± SE for total milk production (TMP) was 4163.39 ± 93.35 kg in lactation period (LP) 313.77 ± 6.56 days for by pneumonia infected cattle. Heritability estimate for pneumonia in cattle was 0.07 and was higher in calfs before (0.31) and after weaning (0.35). Heritability for TMP and LP were 0.10 and 0.19 respectively. Genetic correlations between pneumonia incidence with TMP and LP were -0.46 and -0.0001 respectively. Phenotypic correlations for pneumonia characters with the same parameters were -0.06 and 0.04. Further studies were warranted to study the effect of pneumonia infection on production and reproduction performances in Holstein cattle.

Two different methods were used for harvesting the oocytes of ovine ovaries. The aim was to determined an efficient method for oocyte harvesting and its effect on subsequent in vitro maturation. The average percentage of oocytes recovered was significantly (p<0.05) higher by slicing (84.60 ± 1.01) than by aspiration method (67.60 ± 1.37). While the percentage of good quality mature oocytes was higher in the aspiration method (40.57 ± 0.90) as compared with slicing methods (37.40 ± 0.27). There was a significant difference (p<0.05) between two methods.
It was concluded from this study that the method of harvesting oocytes from ovaries in slaughter house affect the recovery and the maturation of the oocyte in sheep.

The study was conducted to estimate the reproductive performance of two breeding group of Awassi ewes (1208 ewes) bred for two lambing seasons ( 2006 - 2007) under semi-intensive system 300 native Awassi ewes and 908 imported Awassi ewes were joined to rams in the first season (2006) and 135 native Awassi ewes and 378 imported ewes were joined in second season (2007). Fertility (ewes lambed per ewes joined),Twinning percentage (twinning lambing per ewes lambed), Lambing percentage (lambs born per ewes lambed), mortality (lambs died per lambs born ), Prolificacy (lambs weaned per ewes joined) and weaning percentage (lambs weaned per ewes lambed) were tested .
In both lambing season imported ewes were surpassed native group in fertility (93.4% compared with 82.6%), twinning percentage( 21.4% compared with 20.5%), lambing percentage (113% compared with 99.5%), Lamb mortality (8.6% compared with 18.4%), prolificacy (104% compared with 81.2%) and weaning percentage( 111% compared with 98.3%).
Native Awassi ewes improved their reproductive performance in the second season compared with the first season and the improvement was significantly in mortality (7.2% compared with 23.7%) and weaning percentage (97.7% compared with 74%) .
It was concluded that imported Awassi ewes were superior to native ewes under semi-intensive System in there reproductive performance .

A study was conducted in the station of sheep and goats lies ode research shitom relatel to the State Board for Agricultural Researches for the period August 2006 to August 2007.
Were 100 heads of native goats and 181 heads of shami goats imported from Cyprus subjected to this study. All animals ranged from 1.5 to 3 years old, and were fed concentrate (750 grams/head/day), consisted of barley, soybean, wheat bran, limestone and kitchen salt, and (2kg/day/head) alfalfa hay. The two groups were hand matted from August to the end of September. After delivering the first progeny, the productive traits; (birth weight, weaning weight, average daily gain and daily milk yield) and reproduction traits (fertility, kidding rate, and twinning percent) in both herds were recorded
The objective of the study was to carryout a comparison between the native and Shami goats in productive and reproductive traits under semi intensive production system.
The results showed that birth weight (kg); 2.10±0.62 and 2.39±0.80, weaning weight (kg); 19.47±4.00 and 20.46±5.20, and average daily gain (gm); 145±32 and 149±43, for the native and shami goats respectively, and the differences between the two genetic groups were significant (p<0.05). Milk yield for native and Shami groups were; 82±45.37 and 134±76.81 kilograms, respectively (p<0.05).
The two groups differed in the reproductive traits as the fellowing: fertility; 83% and 84%, kidding rate; 1.5 and 1.7, twinning percentage; 40 and 63, for the native and shami goats, respectively.
Shami goats have showed a superiority in growth and reproductive traits. This superiority could be explained as a result of genetic potentiality due to genetic improvement for a long time of shami goats, in contrast to the Iraqi goats, that, undergoing the natural selection only, and experienced no genetic improvement during a long period in the past decades. Consequently, and since it is the beginning for Shami goats in the new environment, it is expected that this breed will show better performance in the next seasons.

This study was carried out to explore the effect of treated containing diets (0,5 and 10%) on some performance traits like total and daily growth rates, scrotal circumference, testicular length, testicular diameter and reproductive hormones (FSH, LH and testosterone) of Awassi male lambs.
Twenty four Awassi male lambs were used (6-7 months of age and 25.5kg average body weight) they were randomly allocated into three equal groups. Ground barley grains were replace by zero, 5 and 10% of chemical and microbial treated corncobs for group 1, 2 and 3 respectively during the preliminary (2weeks) and whole experimental (90 days) period. Green roughages as well as mineral's block were available ad lib. Total and daily growth rates were calculated at the end of experiment, scrotal circumference and testicular length were measured by cloth tape whears testicular diameter was measured by vernier caliber. Blood samples were drawn from jacular vein at the end of experiment, to measure Follicles stimulated hormone(FSH), luitenizing hormone (LH) and testosterone in serum.
Results indicates that supplemented treated corncobs by 5, 10% increased total and daily growth rates. Also, it's effect on lamb’s scrotal circumference, testicular length and diameter was positively significantly (P < 0.05); whereas its effects on sex hormones (FSH, LH and testosterone) was non significant.

Twenty five Awassi lambs weighing 24± 0.5 kg and aged 5 months were employed to investigate the effect of supplementation different levels of Nigella sativa (Ns) and Rosemery officinalis (Ro) in the lamb rations on the physical, chemical characteristics of meat. Lambs were divided into five equal groups and fed randomly one of the following diets. The first group fed on basal diet, composed of concentrate without additives and was the control group (D1).The other tested groups were fed randomly on one of the following diets: D1 diet supplemented with 5 or 7.5 gm NS / Kg DM (D2 and D3 respectively ); D1 diet supplemented with 5 or 7.5 gm RO / Kg DM (D4 and D5 respectively). This was achieved by substituting NS and RO for corn.
The following results were obtained as lambs carcass was stored at 4ºC:
1-Addition of Roesmary powder and Nigella sativa to the rations of Awassi lambs caused a significant increase in pH and water holding capacity (WHC), and a drop in cooking loss and drip loss percent.
2-It was observed that there was a significant increase (p<0.05) in the concentration of myoglobin and, a decrease in the concentration of Total volatile nitrogen (TVN) for D2,D3,D4 and D5 groups ,as compared to the control.
3-It was also resulted a significant decrease (p<0.05) in thiobarbituric acid (TBA),peroxide value (PV) as compared to the control when Roesmary powder and Nigella sativa were included seperatetly to the ration of Awassi lambs.
4-The results also revealed a significant sensory evaluation for flavour,juiciness,tenderness, overall palatability. improvement (p<0.05) in the organoleptic characteristics of minced lambs meat when Roesmary powder and Nigella sativa wee added to the ration of Awassi lambs.
5-Addition of Roesmary powder and Nigella sativa to ration of Awassi lambs led to reduced (p<0.05) the values of total plate count and psychrophilic count for meat during refrigerated storage.
It can be concluded that using Roesmary powder and Nigella sativa as feed addatives to the ration of Awassi lambs had improved the quality characteristics, sensory and microbial safety of minced lambs meat when stored under refrigeration at 4C° while extending the shelf life up to 9 day.

This study was carried out in one of the private sector company for production of table eggs in Babylon province 100km south of Baghdad during the period from the Jully 2005 to 21th of October 2005 to compare the effect of uropygealectomy (Iraqi me-thod) with elevation of dietary calcium on egg production and improvement of egg sh-ell, Haugh unit with yolk index of eggs produced from ISA Brown commercial layer during summer season in Iraq.
Five hundred and seventy six commercial brown laying hens (ISA Brown) caged layers at age of 52 weeks were used in the experiment, uropygealectomy was applied f- or half of the total layers (288 layers).
Hens were randomly distributed for four treatment (with four ruplicants) with144 hens for each treatment and fed with two dietary calcium level.
Treatments were arranged as follow:
T1=Non uropygealectomized hens fed on astandered diet with 3.5%dietary calcium(c-ontrol).
T2=Uropygealectomized hens fed diet 3.5% dietry calcium.
T3=Non uropygealectomized hens fed on adiet elevated it,s calcium to 4.5%.
T4=Uropygealectomized hens fed on adiet with high dietary calcium 4.5%.
This method was applied for the first time to improve egg shell quality with Haugh unit and yolk index in Iraq. Two weeks afterapplication of uropygealectomy, daily egg production was recorded, according to Hen Day (H.D), at the end of each experimental period. Experiment was contined for four periods, four weeks each.At the end of each period egg samples were taken to test the specific traits of egg shell as well as Haugh unit and yolk index.
Result showed high significant differences (p<0.01) for the two treatments of urop- ygealectomy (T2and T4) as compared with the control treatment (T1) for all of the pro- ductive and specific traits which represents percentage of total egg production, crack- ed eggs and marketed eggs in addition to the strength of egg shell which is represented to as egg shell thickness, specific weight, Haugh unit and yolk index.
Results of uropygealectomy treatments indicated also high significant differentes as compared with treatment of elevation of dietary calcium (T3) which are related to percentage of cracked eggs,marketed eggs, egg shell thickness ,specific weight of eggs in addition to Haugh unit and yolk index, while the treatment of elevation of dietary calcium of non uropygealectomy (T3) the results showed high significant differences as compared with control treatment (T1) in relation to percentage of cracked eggs, mark- eted eggs,egg shell thickness and specific weight of eggs while it was not significant for Haugh unit and yolk index.

An experiment was conducted to evaluate the effect of using different types of animal or plant protein (imported or local) concentrates in laying hens diets. A total of 400 hens (38 weeks of age) of ISA BROWN strain were used.
Hens were fed four layer diets (treatments) during all of the experiment period (20 weeks). Diets were containing four types of 10% protein concentrate as follow: imported animal protein concentrate, local animal protein concentrate, imported plant protein concentrate and local plant protein concentrate.
Results of the experiment showed that hens fed on layer diet containing 10% local animal protein concentrate had a significant (P<0.05) reduction in egg production, average of egg weight, number of accumulative eggs and feed conversion ratio than those hens fed on all other treatments. Also, results reveled a significant (P<0.05) improvement in egg quality characteristic for hens fed layer diets containing 10% imported plant protein concentrate as compared to layer hens fed on all other diets. There was no difference in cholesterol concentration between treatments. It can be concluded that layer hens fed local plant protein concentrate were better performance than those fed local animal protein concentrate in this experiment.

This experiment was conducted to study the effect of feeding White Leghorn layers different levels of dehydrated alfalfa meal 0 , 3 , 6 and 9% diet on productive traits and hatchability in hight temperature .
A total of 72 females and 12 males (24 weeks age) were used in this study. Birds were divided randomly on 4 groups of 18 females and 3 males each, during the period from 29 of July to 29 th October.
Data showed that groups fed contained 6 and 9% alfalfa meal had a highly significant increase (p<0.01) in the egg production percentage, body weight, food and water intake and food conversion ratio as compared with control group, while no significant differences in mortality percentage among all groups of the experiment.
Significant increase (p<0.05) in fertility percentage, while there was highly significant increase (p<0.01) in the hatching percentage and significant decrease (p<0.05) in embryonic mortality percentage as compared with the control group.

Full study of 400 broiler from day old to 49 days of age and study of calcium, phosphourus concentration and study of calcium, phosphorus concentration and Newcastle antibody in the serum in birds.
The results revealed the followings:
Treatment 1: given ration contained 20% crude.
Protein +1% calcium (source from calcium carbonate).
Treatment 2: given ration contained 23% crude.
Protein +1% calcium (source from calcium carbonate).
Treatment 3: given ration contained 20% crude.
Protein +1% calcium (source from dicalcium phosphate).
Treatment 4: given ration contained 23% crude.
Protein +1% calcium (source from dicalcium phosphate).
Results proved that broiler feeded on feed contained 23% crude protein + calcium carbonate has increased the level of calcium in the serum of blood derived from broilers, and broilers feeded on feed contained 23% crude protein dicalcium phosphorus in the serum derived from blood of the broilers.
Birds feeded on feed contained 23% crude protein + calcium carbonate has increased the rate of Newcastle antibody in the serum in the birds in comparison to birds feeded on feed contained 23% crude protein + dicalcium phosphate.

Barley seeds were germinated for zero, 24,36,48,60 and 72 hours. Results showed that there are no significant differences in barley's composition (crude protein, ether extract, ash, and total carbohydrate).
This study was carried to find out the effect of germination in improving the nutritional value of barley as compared with treated and non treated barley in Japanese Quail's ration at two levels: 40% and 60% when substituted with yellow corn.
Received 300 birds of Japanese quail at 7 weeks on five experimental diets for 12 weeks with three replicates (20birds/rep).
The (1&2) diets were had 40% & 60% of untreated barley while the (3 & 4) diets were include 40% & 60% of germinated barley. While the fifth diet were used as control.
The results revealed that asignificant differences (P<0.05) among birds fed germinated barley, and those fed untreated barley egg weight, eggs production and food conversion ratio, in that favoring germinated barley at both levels mentioned above.

This study aimed to investigate the sufficiency of two local mineral muds (M.T.M) and (K.M) as compared with the efficiency of using an activated sodium bentonite in restricting the aflatoxins effect on the qualitative characteristics of eggs. (192) female and (96) male of (Cutornix cutornix japonica) birds were randomly distributed and subjected to eight nutrition treatments (from 7-15 weeks of age) as follows (T1: control treatment, T2:2mg/kg aflatoxins feed, T3:2mg/kg feed +0.4% sodium bentonite, T4:2mg/kg aflatoxins feed + 0.8% sodium bentonite, T5: 2mg/kg aflatoxins feed + 0.4% mineral mud M.T.M, T6: 2mg/kg aflatoxins feed + 0.8% mineral mud M.T.M, T7: 2mg/kg aflatoxins feed + 0.4% mineral mud K.M, T8: 2mg/kg aflatoxins feed + 0.8% mineral mud K.M).
The results of statistical analysis indicate that the addition of the two mineral muds and activated sodium bentonite to provender polluted by aflatoxins, showed a significant (P<0.05) improvement in eggs quality (eggs weight, albumin and yolk high, yolk index, shell thickness , percentage weight of yolk , percentage weight of albumin, percentage weight of shell ) The results of these treatments didn't vary significantly from control group results, whereas the existence of aflatoxins in feed without adding the mineral mud caused a significant (P<0.05) decrease in qualitative characteristics of eggs.

The age, growth and mortality rates of Barbus grypus were studied at the Upper Zab river in Iski Kalak village, northern Iraq. Fishes were obtained during the period of October 2005 to November 2006. A total of 276 specimens with total lengths ranged from 14-40.5cm and 17.5-430gm in total weight. The age of fish ranged between 1- 6 years with the domination of age 3 (73 specimens reached 29.9cm in length and 127gm in weight). B. grypus may reached a maximum length of 47.5cm as can be predicated by Von Bertalanffy equation: Lt= 47.5 {l-e-0.35(t+0.15) }
The total mortality rate (Z) for B.grypus reached1.22 at Upper Zab river. The exploitation rate (E) was 0.56 rather than the standard value (0.65). This means an increase in fishing mortality rate. The results showed that B. grypus in this river lives shorter and grow slower compared with other inland water system. Mortality was also higher due to the intensive fishing.

ABSTRACT
A total of 331 specimens of Nabbash ( Abu baratim), Barbus barbulus Heckel were collected from the period of September 2002 to December 2003 from Euphrates river near Al-Mussaib power station. Fish stock assessment were estimated using FAO-ICLARM Stock Assessment Tools (FiSAT). According to Gulland and Holt the values were L∞=60.0cm and K= 0.28. The length of Nabbas at first capture (Lc) was 20cm and the length at first maturation (Lm) was 31.5cm. The mean values of total, natural and fishing mortality rate were 1.08, 0.58 and 0.50 respectively. The annual recruitment patterns for one-year Nabbash has been shown two unequal peaks. The first was the major, continues for 6 months and the highest peak recorded during April reached 15.47%.The results of relative yield per recruit showed that the optimum calculated value (Emax) was 0.55,while the ideal exploitation value (E0.5) was 0.31. The present study concludes that Nabbash in Euphrates river near Al-Massaib power station reached optimum length and age during short live period, the exploitation rate was lowest than optimum, without subjected to over fishing.

A total 96 common carp Cyprinus carpio L. with an average weight of 14.03 gm/fish were assigned randomly into four groups of three replicates for each group , each replicate included 8 fishes . The fish were fed on four diets that were equal in isonitroenons (24.16%) and isocaloric (1408.88 MJ/kg). Both vitamin E and Se were added at levels of 0, 150+0.2 , 300+0.2 and 450+0.2 ml/kg diet for the treatments group T1 , T2 , T3 and T4 respectively . The results showed that supplementation of both vitamin E + Se into the diets increased insignificantly (p>0.05) the T2 and increased significantly (p<0.05) T3 and T4 for weight gain (WG), relative growth ratio (RGR), specific growth ratio (SGR), and protoin intake (PI) and for T4 for food conversion ratio (FCR) as compared T1. There were no significant differences for all treatment in protein efficiency ratio (PER). The results of the blood traits showed significant increases (p<0.05) for T4 for red blood cell count (RBC) , and there were no significant differences (p>0.05) for packed cell volume PCV% and hemoglobin concentration (Hb) .

The aim of this work was to study the age and growth of Goldfish Carassius auratus L. in AL-Habbaniyah Lake. The relationship between total length (L) and weight (W) was expressed by the following equation:
Log W=-5.46 + 3.27 Log L r = 0.98 (P≥0.05).
The obtained results indicated that the growth of goldfish in Habbaniya lake was allometric.The relationship between total length (L) and scale radius (S) expressed by the following equation: L=30.70 + 29.47S, r = 0.829 (p≥0.05).
Age of fish was determined by scales. The age data showed that there were six years classes for both males and females. The most rapid growth in length occurred during the first year of life, while the highest growth in weight occurred during the sixth year of life. Maximum expected length (L∞) was 266 mm and maximum weight (W∞) was 294 gm, that fish can attained.

The common carp Cyprinus carpio L. was exposed to different concentrations of Water Soluble Fraction (WSF) of gas oil fuel. The concentrations were 0.5, 1, 1.5, 2.5, 5 and 10%. The LC50, LC100 and LC0 for the fish in the pollutant were 2, 10 and 0.50% respectively. observed The chronic effect of WSF on the common carp for the effect were.observed during 0, 15, 30, 45 and 120 days. And Included histological aspects gross lesoins of the gills, liver, spleen, kidney, intestine, muscles and brain of the common carp that all reflects the chronic effects of the gas oil fuel on fish.

The experiment was conducted to examine the effect of adding different percentages (0, 2.5, 5.0, 7.5 and 10.0)% of black-seed cake (BSC) to the common carp (Cyprinus carpio, L.) feed.120 fingerlings (7.51.0) gm were distributed randomly into 5 triplicate treatments at a stocking rate of 8 fish per aquarium (70×30×30) cm. Weight increment, growth parameters and haematological indices have been measured. The experiment was confirmed for 12 weeks. The results among the diet treatments showed that the diet contained 10.0% BSC (T5) had the highest: food conversion ratio (2.54), food conversion efficiency (39.66%) protein efficiency ratio (1.229%) and biological productive value (23.965%) and highest apparent digestibility (78.3%) and protein digestibility (93.35%). However, T5 had also showed the highest values of: Hemoglobin (8.9 gm/100ml), Packed Cell Volume (26.81%) Red Blood Cell count (24.22×105) cell/ml and lowest White Blood Cell count (5.01 ×103) cell/ml, whereas controlled treatment showed the lowest values of blood picture indices. Dry matters of flesh of the experimental fish increased with increment addition of BSC percents in the diet, where protein was ranged between 14.22% and 14.9% and lipid between 6.56% and 6.28% comparably with initial percent of flesh protein 12.17% and lipid 5.52% respectively.

This study was carried out to characterize the immunity of whole cell killed antigen of P. multocida by using blood lymphocyte transformation assay through DNA-Labeling with bromodeoxy uridine for measuring cell division and sister chromatide exchange (SCE) formation. Different concentrations of the crud antigen were used to stimulate cells isolated from human, sheep and goats.
The results show that there is a significant variation in blood lymphocyte blastegnesis as a function of concentration of antigens. There was increasing in blood lymphocyte blastegnesis BI%, mitotic activities MI% (replication activityRI %) with decrease of antigens concentration.
The blood lymphocytes from goats were expressed as a highest response to antigen than that cells from human and sheep, however these antigens have not effective on the spontaneous level of sister chromatide exchange in either cell types. These results indicate that blood cell transformation method "Brdurd" more practical, accurate and effective method for evaluation of antigenesity.

During the period from May 2005 till April 2006, a total of 2615 fishes, belonging to seven species were collected from Al-Husainia creek, Karbala province, Iraq. These fishes were infected with 33 species of ecto- and endoparasites. Among the ectoparasites, five monogenetic trematodes were recorded for the first time in Iraq. These monogeneans included: Dactylogyrus rohdeianus from gills of both Barbus luteus and B. sharpeyi, Diplozoon paradoxum from gills of B. luteus, Paradiplozoon homoion from gills of B. xanthopterus, P. megan from gills of both Aspius vorax and B. xanthopterus and P. vojteki from gills of B. xanthopterus. Full description with measurements and illustrations of these parasites were demonstrated.

During the period from November 2000 until the end of October 2001, a total of 336 cyprinid fishes: 216 Barbus luteus and 120 Cyprinion macrostomum, were collected from Greater Zab river, north of Iraq. They were infected with the metacercariae of Diplostomum spathaceum. The prevalence of infection was 54.2% for B. luteus and 65% for C. macrostomum. No significant differences were observed in the infection of male and female fishes of both species with this parasite. Prevalence, mean intensity and mean abundance of infection with D. spathaceum increased with the increase in length of both fish species. The infection with this worm was high during spring and summer and low during autumn and winter.