Effect of different tank colours on some productive parameters of European catfish (Silurus glanis L.) fingerlings

V. Krasteva*, A. Zaikov, M. Yankova
Institute of Fisheries and Aquaculture, 4003 Plovdiv, Bulgaria
(Manuscript received 20 June 2019; accepted for publication 1 December 2019)

Abstract. The present study investigated the growth performance, weight gain, feed conversion ratio, growth and survival rate of European catfish (Silurus glanis L.) fingerlings reared for one month in tanks with different colours. Four colours were used: light blue, white, green and black. The experimental unit was a flow-through system (0.8 L.min-1) consisting of eight tanks with water volume of 30L, continuous air supply and water heaters. Two hundred fish with an average weight of 1.85±0.62g were stocked in each tank. Results from the study demonstrated that the weight gain and the feed conversion ratio were poorly affected by the tested tank colours. Weight gain is slightly higher in groups A (blue) and B (white) than in groups C (green) and D (black). However, no significant difference was found in terms of weight gain among the experimental groups (p>0.05). Survival rate was the highest in group C (91%) followed by group D (88.5%). Thus, for rearing of European catfish fingerlings it is preferable to use dark coloured tanks, which resemble the natural habitat of the fish.

Potential of Gmelina leaf meal diets on the productive and physiological characteristics of growing rabbits

P.C. Jiwuba1*, U.O. Ikpe2, N.L. Azodo1

1Department of Animal Production Technology, Federal College of Agriculture, P.M.B. 7008, Ishiagu, Ebonyi State, Nigeria 2Department of Animal Production Technology, Federal College of Land Resources Technology, Owerri, Imo State, Nigeria

(Manuscript received 2 January 2020; accepted for publication 4 March 2020)

Abstract. Rabbit production is highly attracting attention in the world today due to its reputation in supplying one of the safest meat and other useful animal products. Hence, a 49-day study was carried out to determine the feed intake, body weight gain, serum biochemistry and haematological parameters of 80 growing rabbits fed Gmelina arborea leaf meal (GALM) in their diets. Four diets were formulated: T1, T2, T3 and T4 containing GALM at 0%, 10%, 20% and 30%, respectively. The rabbits were randomly divided into four experimental groups of twenty animals each, with five rabbits constituting a replicate. Blood samples were drawn from each animal on the last day of the trial and evaluated for serum biochemistry and haematological parameters. Results on proximate composition revealed that the nutrient requirements were met. Feed intake and body weight gain (p<0.05) were improved in T4 in comparison with other groups. Feed conversion ratio was however best for T3 and T4 (p<0.05). The haematological parameters differed significantly (p<0.05) and were improved at 30% GALM inclusion across the groups. Results showed that all the serum biochemical parameters studied except globulin differed significantly (p<0.05) among the treatment groups. Cholesterol was reduced at 30% GALM inclusion (p<0.05). All the blood parameters fell within the physiological range for clinically healthy rabbits; an indication that GALM had a beneficial effect on rabbits. Diet T4 had the best performance data among the treatment diets and is therefore recommended for rabbit enhanced production.

Effect of dietary garlic powder and probiotics supplementation on growth performance of male classic broilers

  1. Lukanov1*, I. Pavlova2, A. Genchev1


1Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria

2Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria

(Manuscript received 6 December 2017; accepted for publication 24 January 2018)


Abstract. This study was conducted to evaluate the growth performance of male classic broiler chickens whose feed was supplemented with either garlic powder, probiotics or both. A total of 120 day-old male Ross 308 broiler chickens were divided into 4 groups: first group – control; second group: fed feed supplemented with Lactobacillus spp. probiotic combination; third group: fed feed supplemented with 0.4% garlic powder and fourth group: fed both 0.4% garlic powder and Lactobacillus spp. The experiment lasted until the 35th day of age. The results showed that the highest live weight at the end of the experiment was established in the group supplemented with probiotic+garlic powder (2257.51±3.87g), and the lowest – in the control group (2171.37±4.71g). The group supplemented with probiotic+garlic powder exhibited the highest average weekly weight gain during the 2nd, 3rd and 4th week of life and the highest total weight gain (2211.58±3.91g). The groups fed probiotic and probiotic+garlic powder had the most efficient feed conversion ratios (1.43±0.2). During the study period, there was no substantial decline in the consumption of feed containing 0.4% garlic powder. The supplementation of feed with garlic powder+Lactobacillus spp., had a beneficial effect on the growth performance of broiler chickens. Our data, in line with those of other research studies, suggested that the addition of 0.4% garlic powder combined with Lactobacillus spp. to poultry feed increased meat production in broiler chickens.

Effect of linseed and sunflower oil supplementation in the diet on the growth performance in carp (Cyprinus carpio L.), cultivated in a recirculating system

Abstract. The aim of this study was to determine the influence of linseed and sunflower oil supplementation on the survival rate, weight gain and feed conversion ratio in carp (CyprinuscarpioL.), raised inarecirculating system. The fish in the experiment were reared in concrete tanks that were part of the recirculating system and had a capacity of 0.8 m3. The carps received extruded pellets (6 mm) obtained by “Aqua garant”. For a period of 60 days the feed of the fish of the experimental group (EL) was supplemented with 5 % linseed oil, while the carps of the group (ES) received additionally 5 % sunflower oil with the diet. The fish of the control group (C) received feed without any of the above mentioned vegetable oils. The weight gain of the carps was controlled at 15-days intervals. The live weight (g) and the linear growth (mm) were determined as the fish were weighed and measured individually. The final live weight of the carps of the experimental and control groups was as follows: EL–871.45±240.39 g, ES–849.00±223.22 g and C–819.55±269.91 g. The value of this parameter in the fish of EL groups was by 2.58% and 5.96% higher than those of the individuals of ES and C groups, respectively, but the differences were not significant (P>0.05). This tendency was similar for the linear measurements, as in the carps receiving linseed oil they were the highest. The EL group displayed the lowest feed consumption. The value of this parameter was lower than those of the ES and C groups by 13.90% and 25.74%, respectively. The differences were significant between the control group and the carps supplemented with linseed oil (P<0.05). The survival rate in the fish of the three groups did not differ significantly.