Evaluation of fatty acid profile and naturalness of butter marketed in Bulgaria

N. Naydenova

Department of Animal husbandry – Ruminants and Dairy farming, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria

(Manuscript received 5 June 2021; accepted for publication 30 August 2021)

Abstract. The predominant influence on the structural-mechanical characteristics (hardness, brittleness, etc.) and the chemical parameters (acidity, oxidation-reduction potential, etc.) of butter is exerted by its lipid composition. The aim of the study was to establish the fatty acid composition of some Bulgarian brands of butter and those imported from abroad, offered in the trade network of Bulgaria, in connection with their naturalness and health indicators. Five brands of butter produced in Bulgaria and imported from countries in the European Union were tested three times. The content of saturated fatty acids in the studied Bulgarian brands of butter varied from 66.16 to 75.15%, and for brands of butter imported from EU countries they varied in a significantly narrower range – from 67.51 to 72.49%. The amount of short-chain saturated fatty acids is higher for EU-imported butter brands. The data for the identification characteristics of all tested samples from the trade network of the country meet the requirements for naturalness of butter. The atherogenic index of butter varied from 2.56 to 3.26 for the imported brands of butter and from 2.41 to 3.70 for the Bulgarian ones, and the thrombogenic index from 1.49 to 2.36 for the imported brands, and from 1.44 to 2.17 for the Bulgarian ones, respectively.

Bacteria variety causing clinical mastitis in Holstein-Friesian cows in Pelagonia region, North Macedonia

S. Stojanovski1*, G. Cilev2, B. Trajanoska3

1Department of Microbiology, Faculty of Veterinary Medicine, University “St. Kliment Ohridski”, 7000 Bitola, North Macedonia
2Department of Food Quality and Safety, Faculty of Veterinary Medicine, University “St. Kliment Ohridski”, 7000 Bitola, North Macedonia
3Veterinary clinic “Makseraja”, 7500 Prilep, North Macedonia

(Manuscript received 21 April 2021; accepted for publication 21 June 2021)

Abstract. The main aim of this study are the bacteria that most often cause clinical mastitis (CM) and their impact on milk reduction in Holstein-Friesian cows in the Pelagonia – North Macedonia region. 36 milk samples were taken from Holstein-Friesian breed of cows with confirmed clinical mastitis by a veterinarian. The samples were taken for the period from January 2019 to December 2020 from 20 different smallholder farms situated in the monitored region. Two sterile tubes with 10 ml of milk in each of them were taken from the affected part of the udder of the cow. A total of 86 tubes with milk from 36 mastitis cows were taken. From each sample 300 µl drips were placed in petri dishes with different selective nutrient media: Mannitol Salt Agar, MacConkey Agar, Endo Agar and Edwards nutrient medium. The petri dishes were incubated at 35±2°C for 24-48 hours in Mannitol Salt Agar, at 30-35°C for 18 to 72 hours in MacConkey Agar, at 35±2°C for 18 to 24 hours in Endo Agar and at 35-37°C for 24-48 hours in Edwards nutrient medium. Morphology of colonies and cells were examined with a microscope. A total of 119 strains were obtained and the following physiological and biochemical studies were performed to determine the new isolates: oxidase reaction, catalysis activity, indol test, hydrolysis of the hyporate, acetoin formation (acetylmethylcarbinol, Voges-Proscauer reaction) and Methyl-Roth test (MR- test). The results obtained revealed that the most common bacterial species causing clinical mastitis in Holstein-Friesian cows in 2019 and 2020 were six species of bacteria, where E. coli and Staphylococcus spp. are dominant.

Plant-parasitic nematodes associated with Moringa tree (Moringa oleifera Lam.) in Adamawa, North Eastern Nigeria

M.Y. Jada, M.Y. Adamu, M.B. Aji, G. Abdullahi*

Department of Crop Protection, Modibbo Adama University of Technology, Yola, Adamawa State, Nigeria

(Manuscript received 5 July 2020; accepted for publication 5 April 2021)

Abstract. Moringa (Moringa oleifera Lam.) is becoming an economically important crop because of its nutritional value, therefore, more land area is currently being devoted to its cultivation particularly by vegetable farmers. But right now, little is known about plant-parasitic nematodes as one of its probable pest problems. A survey was, therefore, carried out to determine the plant-parasitic nematodes (PPN) associated with Moringa tree in Adamawa State, Nigeria. Nine of the 21 local government areas (LGAs) of the state were randomly selected; and 10 moringa farms, indicating at least two household/home gardens, were picked from each of the selected local government area for the survey of PPN. In each selected sampling site, soil samples were taken from the base of randomly selected moringa plants to a depth of 15-25 cm using hand trowel and hoe. Composite sample from each LGA from root and soils were taken to Laboratory for nematode extraction. Nematodes were extracted from both soil and roots using Baermann Tray method. The Moringa tree root rhizosphere revealed the presence of 14 genera of plant-parasitic nematodes with specimens from Meloidogyne, Scutellonema, Aphelenchoides, and Hoplolaimus genera being more abundant and frequent. They recorded average prominence value of 123.96, 93.31, 63.83 and 61.83, respectively. Whereas in the roots, Meloidogyne and Scutellonema specimens were found more than the remaining plant-parasitic nematodes genera with an average prominence value of 50.92 and 22.26, respectively.

Nutritional and functional attributes of raw and grilled crabmeat

R.O. Moruf1*, M.A. Taiwo2, Q. Adebayo2

1Department of Fisheries and Aquaculture, Bayero University, Kano, Nigeria
2Department of Food Science and Technology, Federal University Dutsin-Ma, Nigeria

(Manuscript received 4 November 2020; accepted for publication 15 February 2021)

Abstract. Crab is a good source of animal protein, eaten either as snacks or as part of main meal in Southern Nigeria. The effect of grilling on energy-providing nutrients and functional attributes of Cardiosoma armatum (Herklots, 1851) were determined. The comparison of the raw and grilled crabmeat showed that grilling had considerable effect on the quality of this species. Significant changes (p<0.05) in crude fiber (%), calcium (mg/100g), magnesium (mg/100g), potassium (mg/100g), sodium (mg/100g), and oil absorbing capacity (%) were observed after grilling. Utilizable energy due to protein (60% of protein energy utilization assumed) was comparable in both raw (9.36 kJ/9.27 kcal) and grilled samples (10.92 kJ/10.83 kcal). The ratio, Ca/Mg was high with a little variation between the two samples, having coefficient of variation percent of 12.94%. Only calcium had its Mineral Safety Index (MSI) greater than the standard value for both the raw samples (23.68>10.00) and the grilled samples (13.86>10.00). All the significant energy-providing nutrients have a positive correlation with the investigated minerals except magnesium. Grilling was found to be a suitable cooking process for C. armatum, since it conserved the main energy-providing nutrients and functional characteristics.

Isolation and characterization of Lactobacillus microflora from homemade white sheep’s milk cheeses during ripening

S. Stojanovski1*, G. Cilev2, B. Trajanoska3

1Department of Microbiology, Faculty of Veterinary Medicine, University “St. Kliment Ohridski”, 7000 Bitola, North Macedonia
2Department of Food Quality and Safety, Faculty of Veterinary Medicine, University “St. Kliment Ohridski”, 7000 Bitola, North Macedonia
3Veterinary clinic “Makseraja”, 7500 Prilep, North Macedonia

(Manuscript received 24 September 2020; accepted for publication 1 February 2021)

Abstract. The Lactobacillus microflora of white cheese made from sheep’s milk was studied during the maturation period of 10 to 100 days in the basement at a temperature of 10-12°C. Eight samples from different stages of natural white cheese ripening were taken for testing. A total of 28 strains were isolated and identified as Lactobacillus spp. based on their growth, gram-stain activity, catalase and oxidase. Their affiliation to this genus was confirmed by PCR with genus specific primers, 16S ribosomal RNA. The results show that in the early stages of cheese ripening (5th-6th, 10-39 day) the most commonly found species are: Lactobacillus plantarum and Lactobacillus curvatus, while in later stages of the cheese ripening (7th-10th, 40-80 day), the following species are found: Lactobacillus plantarum and Lactobacillus paracasei subsp. Paracasei.

Main parameters of essential oil of two species from genus Pelargonium, cultivated in laboratory conditions

V. Badzhelova*

Institute of Roses, Essential and Medical Cultures, 6100 Kazanlak, Bulgaria

Manuscript received 24 July 2020; accepted for publication 20 January 2021

Abstract. The objective of this study is to determine the quantity and parameters of the obtained essential oil of two species from genus Pelargonium (Pelargonium graveolens L’Her. and Pelargonium radens H.E.Moor) in Bulgaria. This research was conducted using the microdistillation method and gas chromatography. As a result significant difference in the quantity of obtained essential oils has been found and the number of the main components and the ratio of the dominant ingredients have been determined. In general, they represent the main part of the oils – from 45.23 % in Pelargonium radens to 47.60 % in Pelargonium graveolens, respectively. The highest is the content of citronellol+nerol in both species, 38.88 % for Pelargonium radens and 37.97 % for Pelargonium graveolens.

Diversity of Lactobacillus microflora in homemade raw sausages during the ripening

S. Stojanovski1*, G. Cilev2, B. Trajanoska3, K. Stamatova-Yovcheva4, D. Yovchev4

1Department of Microbiology, Faculty of Veterinary Medicine, University “St. Kliment Ohridski”, 7000 Bitola, North Macedonia
2Department of Food Quality and Safety, Faculty of Veterinary Medicine, University “St. Kliment Ohridski”, 7000 Bitola, North Macedonia
3Veterinary clinic “Makseraja”, 7500 Prilep, North Macedonia
4Department of Anatomy, Histology and Embryology, Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria

(Manuscript received 14 September 2020; accepted for publication 23 November 2020)

Abstract. The main purpose of our study is to prove the diversity of the Lactobacillus microflora in domestic raw sausages during ripening. Raw sausages from pork meat (bacon from the neck, front pig shoulder, pork belly) with the addition of salt, red chili pepper and mint were prepared for that purpose. They matured in a maturation chamber for 60 days. A total of 6 samples from different stages of natural ripening of raw sausages were taken for testing. The raw sausage samples were diluted in saline solution, homogenized, serially diluted in the same solution and plated on MRS agar; the plates were incubated at 42°C for 24 – 48 h. A total of 24 strains were isolated and identified as Lactobacillus spp. based on their growth, gram-stain activity, catalase and oxidase. Their affiliation to this genus was confirmed by PCR with genus specific primers, 16S ribosomal RNA. The results show different Lactobacillus species: Lactobacillus plantarum – 37%, Lactobacillus sakei – 28%, Lactobacillus brevis – 20% and Lactobacillus curvatus 15%.

Symbiotic effect on some microbiological species and physicochemical properties in milk in subclinical mastitis of dairy cows

I. Abdennebi1, C.R. Messai2, N. Ouchene3,5*, N.A. Ouchene-khelifi3,5, L. Ghallache4, K. Ait-Oudhia5,6,
T.M. Hamdi1, D. Khelef2

1Laboratory of Food Hygiene and Quality Insurance System, High National Veterinary School, Algiers, Algeria
2Animal Health and Production Laboratory, High National Veterinary School, Algiers, Algeria
3Institute of Veterinary Science, University Blida1, Street Soumaa BP270, 09000 Blida, Algeria
4Environment, Health and Animal Production Laboratory, Institute of Veterinary and Agronomic Sciences,
Batna, Algeria
5Laboratory of Biotechnologies related to animal reproduction, University Blida1, Street Soumaa BP270,
09000 Blida, Algeria
6High National Veterinary School, Algiers, Algeria

(Manuscript received 10 September 2020; accepted for publication 3 November 2020)

Abstract. Subclinical mastitis (SCM) is the most common form of mastitis and the greatest cause for concern in dairy cows. The overuse of antibiotics for the treatment of mastitis leads to the development of resistance, resulting in the use of symbiotics. The study was carried out between February and May 2017 at a pilot dairy cattle farm in the Tipaza region (north-central Algeria) aiming to investigate the effect of a symbiotic on SCM. California Mastitis test (CMT) was used to diagnose SCM in a total of 240 dairy cows. A number of 58/240 (24.16%) cows were found to have SCM. These mastitis cows were then divided into two lots; an experimental lot of 37 cows and a control lot of 21 cows. A symbiotic was administered to the experimental lot once a month for three months. Cell count, microbiological analysis and analysis of certain physicochemical parameters of the milk were applied before and after each administration of the symbiotic. The results revealed that the average somatic cells count (SCC) in cows from the control lot was higher than that of cows from the experimental lot throughout the study period (p<0.0001). Staphylococci were isolated from 51/58 (87.93%) of the mastitis cows, of which 21 (36.20%) were infected with Staphylococcus aureus and 30 (51.72%) with coagulase-negative Staphylococcus. Enterobacteriaceae were isolated from 36/58 (62.07%) of the mastitis cows, of which 21 (36.20%) were due to Escherichia coli strain and 15 (25.86%) to other strains of Enterobacteriaceae. After administration of the symbiotic, the prevalence of S. aureus and E. coli decreased significantly in the experimental lot compared to the control lot (p<0.001). The physicochemical characteristics of the milk were not altered by the administration of the symbiotic. All these results show that the symbiotic constitutes an adequate solution to replace antibiotics in the treatment of SCM.

Antimicrobial activity of lactic acid bacteria isolated from garri on Escherichia coli strains isolated from clinical and environmental samples

H.I. Atta1*, A. Gimba1, T. Bamgbose1,2

1Department of Microbiology, Ahmadu Bello University, Zaria, Nigeria
2Indian Council of Medical Research – National Institute of Malaria Research (ICMR-NIMR), Sector 8,
Dwarka, New Delhi, India

(Manuscript received 15 May 2020; accepted for publication 9 October 2020)

Abstract. The production of bacteriocins by lactic acid bacteria affords them the ability to inhibit the growth of bacteria; they are particularly important in the biocontrol of human and plant pathogens. Lactic acid bacteria have been frequently isolated from fermented foods due to the high acidity these foods contain. In this study, lactic acid bacteria were isolated from garri, a popular Nigerian staple food, which is fermented from cassava, and their antagonistic activity against clinical and environmental isolates of Escherichia coli was determined. The species of Lactobacillus isolated include: Lactobacillus plantarum (50%), Lactobacillus fermentum (20%), Lactobacillus acidophilus (20%), and Lactobacillus salivarius (10%). Growth inhibition of the strains of E.coli was observed in Lactobacillus plantarum that inhibited the growth of both. The clinical and environmental isolates of E. coli were inhibited by Lactobacillus plantarum, while Lactobacillus acidophilus showed activity against only the clinical isolate. The greatest zone of inhibition against the strains of E. coli was recorded by Lactobacillus acidophilus (22.7±1.53 mm). The bacteriocins produced by Lactobacillus species have a good potential in the biocontrol of pathogens, and should be the focus of further studies on antibiotic resistant bacteria.

Influence of Panamin Animal and Panamin Detox on milk coagulation properties of dairy cows

D. Yordanova*, T. Angelova, J. Krastanov, D. Miteva, V. Karabashev, G. Kalaydzhiev

Agricultural institute, 6000 Stara Zagora, Bulgaria

(Manuscript received 10 July 2020; accepted for publication 16 September 2020)

Abstract. The aim of the study was to evaluate the differences in milk coagulation properties in three groups of dairy cows receiving the dietary supplements Panamin Animal and Panamin Detox. The present group production experiment was conducted in the experimental cattle farm of the Agricultural Institute – Stara Zagora with three groups (two experimental and one control) each comprising 11 lactating dairy cows between November 2016 and March 2017. The cows are kept freely, the milking is in a hall “Fish bone”, and the groups were fed balanced rations compliant with milk yield and live body weight of cows, supplemented with 0.50 g/day of two natural dietary additives – Panamin Animal and Panamin Detox in line with recommendations of the manufacturer. The following parameters were monitored: rennet coagulation time (min) – RCT and curd firmness (mm) – a30. The analysis of individual milk coagulation properties was done on 436 milk samples from cows. Individual milk samples were obtained during the morning milking without adding preservative. The analysis of milk coagulation ability was evaluated at the laboratory of the Agricultural Institute – Stara Zagora by means of Computerized Renneting Metter – Polo Trade, Italy. The obtained phenotypes were corrected for main factors influencing test-day milk yield. The used model considered each test day milk yield as independent observation and unbiased estimates of traits were obtained by a linear mixed-effects model. The supplementation of cows’ ration with dietary supplements Panamin Detox and Panamin Animal had a statistically significant beneficial effect on milk coagulation properties of milk (p<0.001). The statistical analysis of group differences in RCT and curd firmness showed highly significant differences between Panamin Animal and control groups for both traits (p<0.001). There was also a highly relevant difference in curd firmness of milk from cows given Panamin Detox supplement and control cows (p<0.001). Data were processed with statistical software products Systat 13 and Pest (Groeneveld), and graphs were generated in MS Excel.