Year:2006 | Volume:18 | Issue:(69 IN ANIMAL AND FISHERIES SCIENCES)|Papers Count:19

One of the major concerns in rangeland is employing a grazing intensity that leads to high animal production as well as sustainable use of the ecosystem. For this aim, different grazing intensities, by Yazdian goat, were tested on steppic rangelands of Yazd province. Experiment was conducted in Nir Research Station and lasted for two years (2000-2001). It was designed as the randomized complete blocks with three replications. In each block high, low and moderate grazing intensities were compared with control (intact) treatment. Grazing was started at the time of range readiness, in a rotational grazing system in which animals were remained for 15 days within each block. Animal performance was determined by measuring weights, breeding percent, fleece and hair production. The research was also aimed to compare goat diet in the field with proposed by NRC (1981) tables. During two years of study, no significant difference (p<0.05) was found in animal live weight, breeding performance, and fleece and hair production between grazing intensity treatments. Although high grazing intensity treatment led to more efficient use of available forage and was economically more important, but the optimum animal performance and sustainable utilization from range lands were obtained only in moderate grazing intensity. Low forage quality influenced grazing behavior of goats; though they had a choice in selecting available forage, utilization were limited on about the maintenance diet level. Therefore animal obtained their maintenance diet at lower phosphorus, protein and metabolic energy, as compared with the NRC tables.

Twenty-five lambs were studied from birth to stage of normal spermatozoid production. These lambs's testis was operated: Two lambs in every month until 120 days of age and three lambs in every 15 days until 180 days of age.  Body weight and testis length, width, weigh and volume were recorded until the time of spermatozoid production.Tissue section and epididymis liquid of operated testis were prepared for microscopic study and determination of semen quality. Semen quality and quantity were examined in six lambs after they produced normal spermatozoid. Normal spermatozoid production was observed by the results of microscopic study and epididymis liquid survey in 165 days old male lambs. This reaction was associated with dramatic increase of body weight, testis weight and volume. The means of these characteristics (body weight, testis weight and volume) were 30kg, 157.57g and 175.33 Cm3 at this age, respectively. Density and activity of spermatozoid were increased after this age (165 days old lambs). Following of this study, the lambs were tested for quantity and quality of semen and sexual behavior until 18 months of age. They did not show any clear sexual trend and collection of semen was impossible by artificial vagina in this period. Sexual trend and semen production were normal after this age (18 months). In this suitable situation 2.4 billion spermatozoids per ml of semen were found in 58 kg of body weight. The result of this study has shown that high sexual capacity and normal spermatozoid production were associated with 58 kg of body weight and 18 months of age in Mehraban male lambs.

In this study 137 published estimations of growth traits from 126875 lambs for 13 breeds in 35 studies during 1980 to 2004 were reviewed to determine factors affecting the estimates, and to make recommendations regarding appropriate mean values. Weighted least-squares analyses were performed with 2 factors (breed and method of estimation) fitted for each parameter's trait. The weighted least square means of performances and direct heritabilities were as, 4.3 kg and 0.16 for birth weight, 23.7 kg and 0.16 for weaning weight, 31.4 kg and 0.19 for weight of 6 months, 39.2 kg and 0.25 for yearling weight and 206 gr and 0.12 for average daily gain from birth to weaning. The maternal effects (maternal heritability and proportion of maternal permanent environment variance to phenotypic variance) accounted for significant part of variation in growth traits and which were reduced with increasing age of lamb. The effect of breed was significant on weighted means of traits and heritabilities (p< 0.05). The effect of estimation method was significant (p<0.05) alone on weighted mean of heritabilities for birth and yearling weights. The results of this study showed that weighted means of growth traits heritabilities to weaning was less than moderate, while for post weaning was more than moderate. Thus, the weighted means for heritabilities presented in this paper are recommended for use when reliable estimates are not available.

2526 specimens of the rock lobsters, Panulirus homarus were caught from Iranian seashores of the Oman Sea during November 1999 to November 2000. Samples were collected by plastic American traps from different fishery stations at Ramin, Chabahar, Puzm and Meidani. Mean weight and length of the lobsters were compared by HSD Tukey test. Length classes of the lobster populations from different fishing sites were acquired using Bhattachrya method. Mean carapace length (mm) and body weight of the specimens were: 74/91x11.09 & 477.3x184.11 in Ramin, 82.57x10.07 & 425.63x155.98 in Chabahar, 71.49x15.33 & 384.69x199.5 in Puzm and 85.54x12.55 & 587.04x215.53 in Meidani, respectively. Results showed that mean weight and length of the lobsters were increased in Puzm, Ramin, Chabahar and Meidani, respectively. Also males had larger length and weight sizes than females. There were 3, 1, 2, and 2 length classes in the lobster populations of Ramin, Chabahar, Puzm and Meidani, respectively. Lobsters with 6.4- 8.2 cm carapace length were dominant in all fishing sites. The best dispersion of length classes was observed in Ramin.

In this survey 68 samples of different brands of sausages with meat content ranges from 40% to 90% produced by different factories, selected via randomly sampling and then protein, moisture, fat, starch and ash were analyzed in all samples by standard methods of Iran. Means and standard deviations of chemical parameters were determined and then compared with standard limits of Iran. This survey showed that means of moisture, protein, fat, starch and ash in sausages (with meat percent of 40-50%) were in order: 54.95±4.16, 12.76±2.38, 20.66±2.24, 9.91±4.14 and In sausages (with meat percent of 51-60%) were moisture 57.32±3.15, protein 12.68±1.88, fat 19.62±3.64, starch 6.64±2.17 and ash 2.98±0.12. In sausages, (with meat percent of 61-90%) were moisture 58.52±5.62, protein 13.99±1.99, fat 17.93±5.71, starch 5.3±3.08 and ash 2.85±0.26. The chemical analysis showed that in sausages with meat content of 40-50 %, moisture in 38.9% of samples were higher than standard limits of Iran, while limits of 50% for starch were also exceeded. In 5.6% of samples protein content were high. In sausages with meat content of 51-60 %, moisture in 38.2% of samples were higher than standard limits' while limits of 14.7 % for fat, 50 % for starch and 93.7% for ash were also exceeded. Protein content in 56.2 % of samples was high. In sausages with meat content of 61-90%, moisture content in 12.5% of samples higher than standard limit, while limit of 75 %for fat, 50 % for starch and 93.7 % for ash were also exceeded. Protein content in 56.2% of samples was high. The results of this study showed that, at least in duration time of this study standard limit of meat products not completely performed by producers in Iran.

The influence of sire, season of parturition, parity, sex and twining on birth weight of Holstein calves were studied. The data used in this study was obtained from the birth weight of 1645 calves born during years of 1995 - 2000 in Kenebist dairy farm, Astan e Ghods Razavi. Results showed the effect of sire was significant (p<0.0001) and birth Weight in winter was significantly (p<0.0001) higher than Spring, Autumn and Summer (39.9±0.55, 38.31±0.51, 37.66±0.54 and 36.08±0.49 Kg respectively). The birth weight was increased while the age of dam increased (Until 5th calving). The birth weight of male calves was significantly (p<0.01) higher than female calves (39.7±0.48 Kg vs 36.27±0.44 Kg, respectively) and single calves had higher weight than twin calves (42.23±0.38 Kg vs 33.75±0.61 Kg, respectively); the difference were significant (p<0.0001). According to these results all of these factors had significant effect on birth weight of calves and calculating of correction factors for each of them can make the birth weights comparable and thus they can be use in selection of the best replacement heifers or breeding bulls.

This experiment was conducted to increase the resistance to environmental stress in larvae of Rainbow trout by feeding of n-3 HUFA enriched Artemia, uauplii. Larvae were reared until 20 days in 4 treatments: 1= artificial food, 2= newly hatched Artemia, 3= enriched Artemia and 4=50% enriched Artemia and 50% artificial food. The best result of resistance to pH stress was observed in larvae that reared on treatment 3 with 98.9±1.9 percent of survival in low pH stress and 66.5±3.7 percent of survival in high pH stress (p<0.05). The best result of resistance to temperature stress was observed in treatment 3 and 4 with 77.8 percent of survival in high temperature stress (p<0.05).

Salmonella abortus ovis is the main causative agent of sheep abortion in Iran. Study of major antigens among different S.abortus ovis strains seems to be useful for designing the effective vaccine. In this experiment 37 S.abortus ovis strains were studied. Western- blot method has been applied to detect major antigens in S.abortus avis strains. All strains developed 5 and 3 major antigens respectively for SS44 and CH-Bakhtiary strains and Varamin strains. Antigens with 26, 15-20 and less than 9 kD yield more effective reaction with serum antibodies. Band of 26kD was identical among all strains. Different S.abortus avis strains revealed both identical and non identical antigens that not only could be used for further epidemiological studies but also assist designing of more effective vaccines for local and universal applications.

In this research, we had tried to produce the oesophageal groove closure reflex by injecting ADH hormone of the posterior hypophysis and follow the procedure by radiography. The following experiments had been performed: 1) Plain radiography of 5 sheep. 2) Radiography of the oesophageal groove area with barium sulfate without hormone injection. 3) Radiography of the oesophageal groove area with Barium sulfate after I.V injection of 0.5 IU/Kg of Lysine Vasopressine hormone. 4) Radiography of the oesophageal groove area with Barium sulfate after I.V injection of 1 IU/Kg of Hormone. 5) Fistulation of Rumen and abomasal fistula and observation of the coloured material Pretruding through the fistula before and after I.V injection of the hormone. 6) Radiographic study of the groove area with barium sulfate after cupper sulfate consumption by the animal. 7) Radiographic study of the groove area after Intra-arterial injection of 1.5 ml hypertonic NaCl solution. 8) Radiographic study of the groove area with Barium sulfate after 48 hours of water deprivation. The results showed that except water deprivation non of the aforementioned experiments oesophageal groove reflex had been Produced and with considering the ADH effects on closure of the groove in cattle there might be some physiological differences existing between cattle and sheep in this respect.

The present study aimed at comparision of three methods of measuring the technical efficiency: Deterministic Frontier Production Function (DFPF), Data Envelopment Analysis (DEA), and Stochastic Frontier Analysis (SFA). Data were collected from 17 broiler Slughter-house Units (SHU) during 1378 to 1380 in Tehran province and then were measured the technical efficiency for each of SHU using each Methods. The Results of this study indicated that: 1) the different methods Results were not significantly different, in other word the value of efficiency was independent of the used methods for measuring the technical efficiency of SHU. 2) The Correlation between the values of technical efficiency was too high. Therefore, the ranking of SHU was independent of the methods used for measuring the technical efficiency. 3) The Sensitivity analysis test of omitting the outliers indicated that the value of technical efficiencies before and after omitting was not significantly different.

The number of 561 cows sera from industrial dairy herds were collected during autumn (161 sample), winter (181 sample), spring 136 sample) and summer (183 sample) from urmia region in iran to investigate: 1-the concentrations of beta hydroxy butyrate (BHBA) in bovine sera. 2- the effects of season on BHBA concentration, and 3- the distribution of subclinical and clinical ketosis in dairy herds. BHBA concentration was measured by spectrophotometer. Mean±SE of BHBA concentration in Autumn, Winter, Spring and Summer were 0.82±0.05, 0.79±0.08, 0.66±0.04 and 0.52±0.09, respectively. Results showed differences among seasons (P0.05). Mean BHBA concentration in Autumn and Winter were significantly (p<0.05) differed from Spring and Summer, while no difference was observed between Autumn and Winter. There were also differences (p<0.01) between BHBA concentration in Summer and Spring. If the BHBA concentration of serurn as classified into 0-0.2 (physiological status), 0.21-1.4 (suspected subclinical), 1.41-3 (subclinical) and >3mmol/l (clinical ketosis), therefore, the distribution were 361 (63.35%), 138 (24.6%), 55(9.8%) and 7 (1.25%), respectively. Results showed differences (X=4.32, df-=3, p<0.05) among them. There were differences (p<0.05) in clinical ketosis between Winter and Summer but not with other seasons. Subclinical ketosis in Summer was differed (p<0.05) with subclinical ketosis in all other seasons. Suspected subclinical ketosis was differed (p<0.05) among seasons. It is concluded that based on the sera BHBA Cone. Subclinical and clinical ketosis could be important in Urmia dairy herds, the BHB concentration of cows sera in Autumn and Winter are at me risk of subclinical to clinical ketosis. On the other hand, clinical ketosis may be important in Winter While subclinical in Autumn. Ketosis is not expected to occur in Summer.

For this purpose the skin specimens were collected from neck, forelimb, hindlimb and abdominal region from 30 apparently healthy and adult Makoyee ewes and were preserved in 10% neutral buffered formaldehyde solution. They were processed through routine paraffin embedding. Sections were cut at 5-7μm and stained with hematoxylin-eosin, Verhoeff elastic and Van Gieson methods. Histological study revealed that, the stratum corneum of epidermis appears in the unevenly laminated form with loose keratin. Papillary region of the dermis was made up of loose connective tissue, whereas the reticular layer was made up of del1se irregular connective tissue, but relative uniformity was observed in collagen fiber diameters. Most of the primary and secondary hair follicles were in anagen or catagen stages, but relatively lesser amounts of them were in telogen stage too. Our observations revealed that apocrine sweat glands are distributed in all of the regions, but their intensity were more in abdominal part. The differences in mean distribution of primary hair follides between all of the regions were not significant, whereas the differences in mean distribution of secondary hair follicles in between all of the regions were highly significant (p<0.001). In all of the regions, there were very significant (p<0.001) difference in mean distribution of primary and secondary hair follicles, and in all of the cases the distribution of secondary follicles was higher than primary once. Relative estimate of secondary and primary folliclesin the neck, forelimb, hindlimb and abdominal regions were 5.05±0.80, 3.25±0.43, 2.58±0.21 and 2.8±0.11 respectively, thus the highest value was belonging to the neck and the lowest one to the hindlimb regions. Mean distribution of fleece stems in compound follicles of neck, forelimb, hindlimb and abdomen regions were 3.1±0.2, 2.85±0.1, 3.2±0.01 and 2.95±0.3 respectively.

Kilka belongs to pelagic fish in the Caspian Sea and they feeds on zooplankton. They are the most abundant fishes of the Caspian Sea. There are three species of kilka fish included of anchovy (Clupeonella engrauliformis, Svetovidov 1941) bigeyes (C grimmi, Kessler, 1877) and Common kilka (C. cultriventris Bordin, 1904). All three species have been existed in Iranian coastal waters and common kilkahad minimum relative frequency. 1.34, 2.5 and 5.5% of total catch belong to it in 1990-91, 1997-98 and 1998-99 respectively. After Mnemiopsis leidyi invasion in the Caspian Sea, relative frequency of this fish increased more than 10%. During 1997 to 2001, some important indexes such as length frequency, weight, sex, sexual maturity stages and age of this fish were studied in catch regions. Spawning of common kilka occurred in Spring in 1997-99 while in 2000-2001 spawning started later, in mass on April and continued to Augusts. We did not see any female at maturity stage VI_II, and stage V was rare. The fork length average was reduced from 92.7mm in 1997 to 81.5 mm in 2000 and increased to 88.3 mmin 2001, but fork length limits were less. The female was dominated. Age structure had 6 age classes (0+- 5+). Age classes 0+- 3+ included 95% during 1997-1999. In 2000 age classes 0+ and 1+ was reduced and 2+ - 4+ were 93.8%. Biological characteristics such as length and age indicated that common kilka population tolerate a pressure but probably because of dispersion of habitat its share in commercial catch has increased during recent years.