Effect of black pepper (Piper nigrum) extract on productive traits, economic efficiency and blood biochemical parameters of rainbow trout (Oncorhynchus mykiss W.)

Ts. Stoev, G. Zhelyazkov

Department of Biology and Aquaculture, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria

(Manuscript received 5 June 2021; accepted for publication 10 August 2021)

Abstract. The aim of the present study was to evaluate the effect of the dietary black pepper extract supplement on the survival rate, weight gain, feed conversion ratio (FCR), economic efficiency (ECR) and blood biochemical parameters of rainbow trout, cultivated in a recirculation system. One hundred and twenty rainbow trout were distributed in two experimental variants, with two replicates of 30 fish per each. The average initial live weight of fish from the control group (C) and experimental group (P.n) were 41.55±7.96 g and 41.23±8.38 g, respectively (p>0.05). Trouts were fed extruded feed with granule size of 2 mm. Through lubrication of feed granules with 5 ml sunflower oil per 100 g feed, rainbow trouts from group P.n were supplemented with 1% powdered black pepper extract, whereas control rainbow trouts (С) received feed lubricated with the same amount of sunflower oil. Fish were fed 3 times/daily with the diet, based on 3% of biomass. The trial period was 60 days. Survival rate in trouts from both experimental groups was 100%. At the end of the trial, average live weight of fish from group P.n was by 5.84% higher compared to that of control fish the average weight of which was 117.25±19.15 g, yet differences were not statistically significant (p>0.05). The average individual weight gain of control rainbow trouts was 75.70±11.53 g, which was inferior to that of P.n fish by 8.65% (p>0.05). Better FCR was demonstrated in trouts from the group supplemented with 1% black pepper extract – 0.98±0.02, which was by 10.20% less compared to control fish (p<0.01). The addition of 1% black pepper extract to the feed of rainbow trouts tended to result a trend in better growth performance parameters in this species. ECR of group P.n was by 3.98% better than that of the control fish, which showed an ESR value of 1.51. Blood biochemical parameters of fish from both groups were not consistently different.

Application of rosemary essential oil (Rosmarinus officinalis Linnaeus, 1753) for anesthesia and transport of bighead carp (Hypophthalmichthys nobilis Richardson, 1845) fingerlings

V. Krasteva*, M. Yankova, A. Ivanova

Institute of Fisheries and Aquaculture, 4003 Plovdiv, Bulgaria

(Manuscript received 17 June 2021; accepted for publication 11 August 2021

Abstract. The aim of the present research is to study the efficacy of rosemary oil as an anesthetic for bighead carp (Hypophthalmichthys nobilis Richardson, 1845) and as an anesthetic used for transport of fingerlings. The fish used in the experiment have an average body weight (BW, g) of 42.13±17.90 and an average total length (TL, cm) of 16.54±2.32. Five treatments are conducted with five experimental concentrations: 0.20 ml.l-1, 0.30 ml.l-1, 0.40 ml.l-1, 0.50 ml.l-1 and 0.60 ml.l-1. For each concentration 10 fish are used or a total of 50 fish. For the transport experiment, 3 concentrations are used: 0.06 ml.l-1, 0.08 ml.l-1 and 0.10 ml.l-1. The applied stocking density is 3 fish/l. A total of 60 fish are used for each concentration or a total of 180 fish. The established results, for the first experiment, show that at concentration of 0.60 ml.l-1 the induction of anesthesia is the fastest (3.46 min). From all tested concentrations the recovery time is the shortest at the lowest concentration – 2.16 min (p≤0.001). The concentration of 0.10 ml.l-1 of rosemary oil can be used for transport of bighead carp fingerlings for a period from 1 to 2 hours. The concentration of 0.08 ml.l-1 can be applied when the duration of the transport is from 1 to 3 hours.

Influence of soybean meal replacement with high-protein sunflower meal on “Clarcs of energy distribution/protein transformation” in broiler chickens

S. Chobanova1, D. Penkov2*

1Department of Morphology, Physiology and Nutrition, Section Animal Nutrition, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria
2Department of Animal Sciences, Faculty of Agronomy, Agricultural University, 12 D. Mendeleev Str., 4000 Plovdiv, Bulgaria

(Manuscript received 28 May 2021; accepted for publication 30 June 2021)

Abstract. The aim of the study is to compare the net utilization of energy and protein in the eco-technical chain „feed-meat“ when replacing part of the soybean meal with high-protein sunflower meal in broiler fattening. One control and 3 experimental groups, 4-phases fattening with isoenergetic and isoprotein combined fodders. Main protein source in the fodders for the control group is soybean meal. Replacement with sunflower meal: First experimental group: Starter – 5%, Grower – 8%, Finisher 1 – 10% and Finisher 2 – 10%; Second experimental group: 15, 18, 25 and 25%, respectively; Third experimental group: 34.25, 27.27, 27.27 and 26%, respectively. Clarcs of energy distribution/protein transformation (CED/CPT) are the ratio between accumulated gross energy/crude protein in breast and thigh muscles and consumed metabolic energy/crude protein throughout life. The following results were established: CED “fodder – breast+thigh muscles”: Control – 0.2430, first experimental group – 0.2394, second experimental group – 0.2505, third experimental group – 0.2334; CPT – 0.6080, 0.5050, 0.5280 and 0.5490, respectively.

Photosynthetic activity and productivity of durum wheat (Triticum durum Desf.) affected by certain preparations and various terms of sowing

P. Nikolov1*, G. Delchev2

1Institute of Agriculture and Seed Science “Obrazcov Chiflik”, 7007 Ruse, Bulgaria
2Department of Plant Production, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria

(Manuscript received 31 May 2021; accepted for publication 23 July 2021)

Abstract: In 2019-2020, in the experimental field of the Field Crops Institute, Chirpan a field experiment with durum wheat cultivar Predel (Triticum durum Desf.) was conducted. Three sowing dates were tested: Early sowing (05 – 10 October), Normal sowing (20-25 October – standard) and Late sowing (05-10 November). In early sowing, 2 retardants were studied: Cearon 480 SL – 1 l/ha and Medax top – 1 l/ha and 2 insecticides: Proteus 110 OD – 625 ml/ha and Mageos – 100 g/ha, as well as the mixtures between them. During late sowing, 2 stimulants were studied: Naturamin plus – 1.5 l/ha and Raiza mix – 750 ml/ha and 2 foliar liquid fertilizers: Mix for cereal SC – 1.5 l/ha and Trimax SC – 1.5 l/ha, as well as the mixtures between them. These preparations and fertilizers are applied after stage 3-4 leaves of durum wheat, in the so-called “Closure of crops”. In the case of early sowing variants, this stage occurs in autumn, and in the case of late sowing variants, the stage occurs in spring. In the early sowing of durum wheat, the leaf area, photosynthetic potential, biological and economic yield are the greatest in the combinations of retardants Cearon and Medax top with the insecticides Proteus and Mageos. In the late sowing of durum wheat, the leaf area, photosynthetic potential, biological and economic yield are the highest in the combinations of the stimulants Naturamin plus and Raiza mix with the leaf fertilizers Mix for cereals and Trimax. In these variants, the leaf area dies faster during the milk development stage. The net photosynthesis productivity in the combinations is lower than in the independent use of the respective preparations and fertilizers. The harvest index in the late and normal sowing variants is higher than in the early durum wheat sowing variants.

Comparative study of some phenotypic characteristics between the Ispenc (Turkey) and Southwestern Bulgarian dzhinka chicken breeds

I. Pavlova1, D. Özdemir2, H. Lukanov3*

1Department of General Livestock Breeding, Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria
2Department of Agricultural Biotechnology, Faculty of Agriculture, Akdeniz Üniversity, Antalia, Turkey
3Department of Animal Husbandry – Мonogastric and other animals, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria

(Manuscript received 11 June 2021; accepted for publication 14 July 2021)

Abstract. Ispenc and the Southwestern Bulgarian dzhinka are two small chicken breeds, originating respectively from two neighboring countries – Turkey and Bulgaria. They are characterized by uniformity in some major mutational exterior traits, such as beard and muffs, shank-feathering, vulture hocks, and rose comb. The aim of the study was to compare some of the main morphological and morphometric features of the Ispenc and Southwestern Bulgarian dzhinka breeds. The study was performed on 15 roosters and 25 hens of each breed. Ispenc had a significantly higher live body weight, respectively by 19.65% in roosters and by 17.11% in hens, compared to the Southwestern Bulgarian dzhinka (p<0.001). The birds of the Turkish breed are polydactyl, 5-toed, while the Bulgarian breed does not have this mutation. The length of the back, the wingspan and the length of the shank in Ispenc were significantly higher in both sexes, compared to the Southwestern Bulgarian dzhinka (p<0.01). The comb of the Bulgarian breed is more compact, with significantly lower values in terms of its width (p<0.001). In terms of the dimensions of the head and its formations, there are more statistically significant differences between hens of the two breeds than between roosters. The study leads to the conclusion that the seemingly close breeds involved in the study show a number of statistically significant phenotypic differences, which suggests differences in their genotype.

Biometric data of peach and nectarine fruit and stones

A. Zhivondov1, S. Savchovska1, S. Pandova1, D. Petkova2*, P. Doykina3, I. Manolov4

1Department of Breeding and Genetic Resources, Fruit Growing Institute, 4000 Plovdiv, Bulgaria
2Department of Biotechnology, Technological Faculty, University of Food Technologies, 4002 Plovdiv, Bulgaria
3Department of Catering and Tourism, Economics Faculty, University of Food Technologies, 4002 Plovdiv, Bulgaria
4Department of Agrochemistry and Soil Science, Faculty of Agronomy, Agricultural University, 4000 Plovdiv, Bulgaria

(Manuscript received 3 June 2021; accepted for publication 26 July 2021)

Abstract. The article presents a three-year traceability (2018, 2019, 2020) of biometric results of the fruits of eight peach and nectarine varieties. The study covers the fifth, sixth and seventh vegetation period from the period of full fruiting. Varieties included in this investigation were “Filina” (peach, clingstone), “Gergana” (nectarine, clingstone), “July Lady” (peach, semi-clingstone), “Ufo 4” (flat peach, semi-clingstone), “Laskava” (peach, freestone), “Morsiani 90” (nectarine, freestone), “Flat Queen” (flat peach, freestone), and “Evmolpiya” (peach, freestone). The experimental collection plantation was created in the spring of 2014 on the territory of the Fruit Growing Research Institute, Plovdiv, (lat. 42.10384828045957 and long. 24.72164848814686). The data analysis shows that the varieties “Laskava” and “Evmolpiya” produce fruits with the highest weight – 319.60 g and 303.60 g, respectively. Medium weight is registered in the “Morsiani 90” variety (226.07 g) and the “July Lady” variety (193.87 g). “UFO 4” is characterized with the smallest fruits – an average of 143.83 g and the highest flesh yield. Considering the fact that the “Filina” variety is very early ripening, its fruits can be treated as large for the season – 170.21 g. The stones of the “July Lady”, “Morsiani 90” and “Evmolpiya” varieties have the largest average mass

Breeding assessment of new promising cotton lines

V. Dimitrova, R. Dragov

Field Crops Institute – Chirpan, 6200 Chirpan, Bulgaria

(Manuscript received 7 June 2021; accepted for publication 2 August 2021)

Abstract. Cotton breeding in Bulgaria is mainly aimed at improving the earliness, productivity and fiber quality of modern varieties. The creation of new genetic diversity is one of the basic prerequisites for the success of breeding programs. The aim of the study was to evaluate cotton lines obtained by intraspecific and remote hybridization combined with backcross technology, with a view to their most effective usage in selection. Twenty-three lines were included in competitive variety trials conducted during the 2014-2017 period. The averaged results showed that lines 550, 639, 641, obtained by remote hybridization, appeared to be very promising. These three lines were distinguished by the best combination of productivity, fiber length and fiber lint percentage, and by these three indicators they exceeded the standard variety Chirpan-539. A new cotton variety Aida (No. 457) was approved, which in seed cotton yield and fiber yield, and technological fiber properties surpassed the standard varieties Chirpan-539 for earliness and productivity and Avangard-264 for fiber quality. The candidate variety 535 continued the state variety testing. Two new candidate cotton varieties No. 550 and No. 553 were released. In the state variety testing the three candidate varieties confirmed their qualities. The obtained lines, distinguished by one trait or by a complex of qualities, enriched the gene pool of Bulgarian cotton.

The endemic plants – a valuable resource with vast potential in Bulgaria: A brief overview

D.T. Petkova*, D.Sp. Mihaylova

Department of Biotechnology, Technological Faculty, University of Food Technologies, 4002 Plovdiv, Bulgaria

(Manuscript received 3 June 2021; accepted for publication 21 July 2021)

Abstract. The plant kingdom with its natural products, both terrestrial and marine, has been widely studied. Plant-based products have long been used for the prevention and treatment of various diseases. Many natural compounds are reported to have a number of interesting and significant biological activities, such as antioxidant, anti-inflammatory, antitumor, antibacterial, antiviral, antifungal, antiparasitic, analgesic, antidiabetic, antiatherogenic, antiproliferative, and cardioprotective and neuroprotective activities. In order to find a natural product, researchers often explore the possibilities given by nature. Special attention is paid to bioactive compounds synthesized by endemic plants as a specific resource of limited habitat. This review focuses on a brief overview of endemic plants in Bulgaria, most common in the mountainous regions of the country, with the aim to encourage the knowledge of these resources with vast potential for unique biological compounds and specific characteristics beneficial to humans for various purposes.

Isolation of Lactobacillus species from fermented Parkia biglobosa seed and screening for their probiotic activity

K. Kuti1, I.M. Hussaini1*, A. Usman2, A. Isa1

1Department of Microbiology, Faculty of Life Sciences, Ahmadu Bello University, Zaria, Nigeria
2Department of Microbiology, Faculty of Science, Kaduna State University, Kaduna, Nigeria

(Manuscript received 24 December 2020; accepted for publication 10 May 2021)

Abstract. Food fermentation has been a tradition for decades due to its immense benefits. Lactic acid bacteria are known to possess probiotic potential due to various chemical antimicrobial substances they produce. This research was aimed at isolating Lactobacillus spp. from locally fermented locust beans and screening the isolates for their probiotic potential. A total of 20 samples of fermented locust beans (P. biglobosa) were collected and processed. The samples were inoculated onto de-Mann Rogosa Sharpe (MRS) media and incubated anaerobically. The isolates with characteristic colonial morphology of Lactobacillus sp. were characterized using Gram staining and biochemical tests. Lactobacillus spp. isolates were screened in-vitro for probiotic potential using the following parameters, tolerance of low pH, bile tolerance and antimicrobial activity. Four isolates of Lactobacillus species consisting of Lactobacillus fermentum and Lactobacillus plantarum were isolated from different fermented locust beans. All isolates showed tolerance to low pH and bile concentration of 3.04 and 0.3%, respectively. The Lactobacillus species isolates showed varying antibacterial activity against all test bacteria with isolate S06 (L. plantarum) showing the highest degree of antibacterial activity. In conclusion, the Lactobacillus species isolated from fermented locust beans can serve as probiotic candidate.


Assessing resource utilisation in beef cattle feedlot system in Adamawa State, Nigeria

M.R. Ja’afar-Furo1*, M.Y. Hamid1, A.Y. Thlaffa1, A. Sulaiman2

1Department of Agricultural Economics and Extension, Faculty of Agriculture, Adamawa State University, PMB 25, Mubi, Nigeria
2Department of Agricultural Economics and Extension, School of Agriculture and Agricultural Technology, Abubakar Tafawa Balewa University, Bauchi, Nigeria

(Manuscript received 20 July 2020; accepted for publication 24 March 2021)

Abstract. This study assessed resource utilisation in beef cattle fattening units in Adamawa State, Nigeria, with the intent of highlighting some crucial areas that may require policy intervention for improvement. Purposive, multistage and random sampling methods were employed in selection of 270 beef cattle fatteners in the area studied. Structured questionnaire and group discussion were used in sourcing for data. The latter were analysed through descriptive statistics and efficiency methods of Data Enveloping Analysis (DEA). Results indicated that Sokoto gudali (72.60%) and Rahaji (20.00%) were the major cattle breeds adopted for fattening. While a total of 70.70% of fatteners fed bulls for a period of 4-6 months and in the open without shade (77.80%), the use of combination of crop residues and conventional feeds was the most popular (74.81%) in feeding stock in the State. Further, the most important resources were initial cost of bulls and cost of feeds with N169,056.00 and N10,559.00 per bull, respectively. Resources were found to be efficiently utilised within the beef cattle feedlot farms with Constant Return to Scale (CRS), Non-Increasing Return to Scale (NIRTS), Variable Return to Scale (VRS), Scale Efficiency (SE) and Return to Scale RTS) models mean scores of 84.44%, 84.44%, 91.48%, 84.74%, and 100%, respectively. Conclusively, it could be stated that indigenous breeds of Sokoto gudali and Rahaji were the main bulls used for fattening in the State, and a mixture of crop residues and conventional feeds was the popular plane of feeding stock, with most farms utilising resources efficiently. Stemming from the findings, soft credit facilities to accord fatteners afford initial off-setting cost of bulls and frequent extension services to same, for modernisation of beef cattle feedlot system are highly recommended.