Effect of dietary phytoextracts supplementation on the chemical composition and fatty acid profile of rainbow trout (Oncorhynchus Mykiss w.), cultivated in recirculation system

  1. Georgieva, G. Zhelyazkov, Y. Staykov, D. Georgiev

 

Department of Biology and Aquaculture, Faculty of Agriculture, Trakia University, 6014 Stara Zagora, Bulgaria

 

DOI: 10.15547/ast.2018.03.041

(Manuscript received 7 June 2018; accepted for publication 28 August 2018)

 

Abstract. The present research aimed to examine the effect of dietary phytoextracts supplementation on the chemical composition and fatty acid profile in the meat of rainbow trout (Oncorhynchus mykiss W.), cultivated in a recirculation system. The fish were divided into 6 groups: one control (C) and five experimental groups in the food of which phytoextracts of curcumin (EC), paprika (EP), thyme (ET), oregano (EO) and garlic (EG) were added. The inclusion of phytoextracts had no significant effect on growth parameters of fish from EC, EP, ET, EO and EG groups (P>0.05). No statistical differences on water content, protein and lipids were observed in the meat of fish from the control and the experimental groups (P>0.05). Statistically significantly higher value of the dry matter was established in ET group in comparson with C, EC, EP, EO and EG groups (P≤0.001). The values of ash were significantly lower in fish from all experimental groups compared to the control group. The inclusion of phytoextracts did not affect the fatty acid profile of fish from EP, EO and EG groups (P>0.05). Exceptions are EC and ET groups, which had the lowest value of C18:3n-3 α-linolenic compared to those from the control group (P≤0.05, P≤0.001).

Effect of experimentally induced aflatoxicosis on haematological parameters and bone marrow morphology in mulard ducks

  1. Valchev1, N. Groseva2, D. Kanakov1, Ts. Hristov1, L. Lazarov1, R. Binev1

1Department of Internal Non-Infectious Diseases, Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria,

2Department of General and Clinical Pathology, Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria

 

DOI: 10.15547/ast.2018.03.040

(Manuscript received 12 June 2018; accepted for publication 20 August 2018)

 

Abstract. In this experiment, the toxic effects of AFB1 on some haematological parameters were investigated in mulard ducks, namely red blood cell counts (RBC), haemoglobin content (HGB), haematocrit (HCT), platelet counts (PLT), white blood cell counts (WBC), differential white blood cell counts (WBC %), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC). Experiments were conducted with 4 groups of 20 10-day-old mulard ducks each. The groups were as followed: group I – control, fed a standard compound feed according to the species and the age; group II – experimental, whose feed was supplemented with 0.5 mg/kg AFB1, group III – experimental, supplemented with 0.8 mg/kg AFB1 and group IV – experimental, supplemented with 0.5 mg/kg AFB1 and 2 g/kg Mycotox NG. The duration of the experiment was 42 days. Haematological analysis performed on the 21st day of the trial showed reduction in RBC, HCT, HGB and PLT and increased total WBC in groups II and III. The percentages of the different leukocyte classes (differential leukocyte counts) demonstrated increased proportion of heterophils and lower percentages of lymphocytes. The observed changed tended to become more pronounced on the 42nd day of the experiment. There were no statistically significant changes in MCV, MCH, and MCHC, as well as in eosinophil, basophil, and monocyte percentages between control and treated groups (р>0.05). The supplementation of the feed with mycosorbent – Mycotox NG (experimental group IV) reduced partly the harmful effect of AFB1 on the studied haematological indices.

Effect of monosodium glutamate dietary supplementation on some productive traits of common carp (Cyprinus carpio L.), cultivated in net cages

  1. G. Zhelyazkov*

 

Department of Biology and Aquaculture, Faculty of Agriculture, Trakia University, 6014 Stara Zagora, Bulgaria

 

DOI: 10.15547/ast.2018.03.039

(Manuscript received 30 May 2018; accepted for publication 15 August 2018)

 

Abstract. The aim of the study was to determine the effect of a monosodium glutamate dietary supplementation on the survival rate, growth performance, feed conversion ratio and economic efficiency of common carp (Cyprinus carpio L.), cultivated in net cages. Two hundred carps were allotted into two experimental variants, each of them comprising two replications (Control groups – CG and CG1; Experimental groups – EG and EG1), with 50 fish in a group. The average initial live weight of fish from the control and experimental groups was 1141.62±79.62g and 1129.54±71.47g, respectively (P>0.05). The carps were cultivated in net cages with a size 3.0/3.0/2.0m. The fish were fed with extruded feed Aqua garant VITAL, a product of Garant-Tiernahrung Gesellschaft m.b.H. – Austria, with 6mm size of pellets. Monosodium glutamate in amount of 1% was added to the feed of carps from the experimental groups. The fish from the control groups received no monosodium glutamate supplementation of the diet. The feed given to the fish was 2% of the total biomass. The trial period was 60 days, control catch at 30th day were done in order to study the influence of the monosodium glutamate supplementation on the weight gain and feed conversion ratio of the common carp, cultivated in net cages. The initial (1st day), control (30th day) and final (60th day) live weights (g) were determined by individual weighing. The final live weight of the fish from both replications of the experimental and the control groups was as follows: 1699.36±78.43g and 1597.27±74.66g, the differences were significant (P<0.001). The survival rate of carps from both control and experimental group replications was 100%. The average individual weight gain of fish from the two replications (supplemented with 1% monosodium glutamate) was 569.82±3.75g which was higher than that of controls by 20.04%, the differences were significant (P<0.001). At the end of the trial, the analysis of consumed feed amount showed that feed conversion ratio in the group supplemented with 1% monosodium glutamate was 1.76±0.12, i.e. by 25.57% lower than that of control carps (P<0.001). The economic efficiency in the experimental groups exhibited better economic conversion ratio (0.936), by 22.65% lower than that of the non-supplemented groups.

Variability and grain yield potential of maize (Zea mays L.) genotypes under irrigated condition in central Sudan

M.B. Alhussein1, S.H. Suliman2, A.A. Mohammed3

 

1Maize research program, Agricultural Research Corporation, Wad Medani, Sudan

2Crop sciences section, Faculty of Agricultural Sciences, University of Gezira, Wad Medani, Sudan

3Maize research program, Agricultural Research Corporation, Wad Medani, Sudan

 

DOI: 10.15547/ast.2018.03.038

(Manuscript received 25 May 2018; accepted for publication 27 August 2018)

 

Abstract. These experiments were conducted in two different sites to study the genetic variability and the mean performance of the elite different origin maize genotypes under irrigated condition in central region of Sudan during rainy season of 2015. The experiments were arranged in randomized complete block design with three replicates, the data were collected on days to 50% tasseling and silking, plant and ear height, ear length and diameter and grain yield. The analysis of variance for each site and cross sites showed a significant variability among tested genotypes for grain yield, days to 50% tasseling and silking, plant and ear height, ear length and diameter. Also significant differences were observed for genotypes, site and a cross site for most of the studied traits such as for grain yield, days to 50% tasseling and silking, plant and ear height, ear length and diameter. The combined results for genotypic coefficients of variability and broad sense heritability estimates grain yield, ear length and ear diameter varied significantly among the tested genotypes.

Sources of resistance in chickpea (Cicer arietinum L.) to ascochyta blight (Ascochyta rabiei)

  1. Koleva1, Y. Stanoeva2, I. Kiryakov2, A. Ivanova1

 

1Department of Crop Science and Plant protection, College Dobrich, University Bishop Konstantin Preslavski-Shumen, 9300 Dobrich, Bulgaria

2Dobroudzha Agricultural Institute, 9520 General Toshevo, Bulgaria

 

DOI: 10.15547/ast.2018.03.037

(Manuscript received 4 June 2018; accepted for publication 3 August 2018)

 

Abstract. Ascochyta blight is the major biotic stress that causes significant yield losses in chickpea (Cicer arietinum L.) all over the world. The disease is caused by the fungus Ascochyta rabiei (Pass.) Lab (telemorph Dydimella rabiei = Mycosphaerella rabiei (Kovachevski) v. Arx. The use of resistant cultivars is widely acknowledged as the most economic and environmentally friendly method for disease control. The aim of this study is to screen chickpea cultivars and lines for resistance to ascochyta blight with a view for using them in a breeding program. The investigations were carried out during 2012-2017 in Dobroudzha Agricultural Institute (DAI) – General Toshevo. Twenty chickpea accessions were inoculated under field and greenhouse conditions with 30 Ascochyta rabiei isolates. Disease reaction was estimated after 14 days by using 9-degree scale. Disease incidence (DI) was calculated according to the Mc Kinney index. Cluster analysis was used to group the accessions and isolates according to the DI. Nine accessions showed middle resistance under field conditions during the three years of investigations. No immune or resistant accession to all 30 isolates was found under greenhouse conditions. The cluster analysis grouped the accessions into two major classes. One of the classes consists of two accessions (XOOC01CA0490B0223D and XOOC01CA0490B2140D) which showed middle resistance to 12 and 13 of the isolates, respectively. The cluster analysis grouped the isolates into classes, subclasses and sub sub classes according to their virulence to the 20 chickpea accessions. The highest virulence showed five isolates (AR 883, AR 061, AR R1, AR 1013, AR 1015) with DI from 5.40 to 9.00 in all accessions. Differences in field and greenhouse results were expected and they were due to the strong dependence of disease development to climatic conditions. The results in this investigation showed that two chickpea accessions can be used in a breeding program for ascochyta blight resistance.

Knezha 560 – a new mid-late maize hybrid

  1. V. Valkova, N. Petrovska

 

Maize Research Institute, 5835 Knezha, Bulgaria

 

DOI: 10.15547/ast.2018.03.036

(Manuscript received 14 May 2018; accepted for publication 29 June 2018)

 

Abstract. Тhe article presents a short characteristic of morphological, biological and economic qualities of a new maize hybrid Knezha (Kn) 560. The hybrid is a single cross, from mid-late group – FAO 500-599. It is recognized in 2017 by the Expert Commission of Executive Agency of Variety Testing, Field Inspection and Seed Control (EAVTFISC). At the points of ecological variety trails (EVT) and EAVTFISC it was compared with the American hybrid PR 35 P 12 and the Bulgarian hybrid – Knezha 509. During the testing period in the experimental field of the Maize Research Institute (MRI) – town of Knezha, the three-year average grain yield of hybrid Knezha 560 exceeded the standard PR 35 Р 12 hybrid by 19.3% and Knezha 509 hybrid by 37.3%. In the EAVTFISC system, the new hybrid exceeds the middle standard by 0.8%. The hybrid is stress-tolerant and resistant to economically important diseases and pests of maize. With this high-yielding and competitive maize hybrid, the group of mid-late maize hybrids offered on the Bulgarian seed market is being filled.