Effect of humic acid and probiotics on immunity of broiler chickens.

Background: The immune system in chickens has a fundamental role in controlling many diseases based on vaccination, thus enhancement of the immune system response is a priority. Aim: The aim of this experiment was to study the effect of probiotics and humic acid on immunity of broiler chickens. Methods: Day-old 300 Ross broiler chicks were segregated into 5 groups of 60 chicks per group. Group C was considered as a control. Groups T1, T2, T3, and T4 were given probiotics, antibiotics, humic acid for the first 7 days and humic acid for 42 days, respectively. Samples were collected on days 27 and 42 to assess the humoral immunity, cellular immunity, lymphoid organs weight, and differential leucocyte count (DLC). Results: The results showed a significant increase (p < 0.05) in antibodies titer against Newcastle disease virus in chickens given humic acid (T4) daily for 42 days as compared to the control. There was also a significant increase in antibodies titer in the T1 group given probiotic for the first week lasting up to day 27 as compared to the control. The skin thickness of T4 group showed a significant increase as compared to T1 and T2 groups after 24 hours of DNCB challenge. After 48 hours, the thickness was still significantly higher in the T4 group as compared to other groups except for the control. There were no significant differences in Bursa of Fabricius/Body weight (%) between the groups. Spleen/Body weight (%) was significantly higher in the control group and T1 than the other groups on day 42. The DLC remains normal in all groups. Conclusion: It is concluded that the humic acid has a stimulant and strengthening effect on the humoral and cellular immune system when given daily to broiler chickens. Moreover, the use of humic acid and probiotics with good hygiene in the first week of age may alternate the use of antibiotics which could be toxic and raise bacterial resistance.

Prevalence of Salmonella in poultry slaughterhouses located in Tripoli, Libya.

Background: Salmonella is a leading cause of severe economic losses in poultry and foodborne illness in humans worldwide. Aim: The aim of this study was to determine the prevalence and multidrug resistance of Salmonella Enteritidis (S. Enteritidis) in several chicken abattoirs in Tripoli, Libya. The study includes the South, East, and West regions of Tripoli. Methods: Each region was assigned five slaughterhouses. Each chicken slaughterhouse was visited three times to collect samples. Five samples were taken at random from the neck skin, crop, and spleen. The total number of samples collected from all regions was 675. Bacterial isolation and identification, as well as antibiotic sensitivity testing, were performed on these samples. Results: Salmonella spp. was found to be 15% prevalent, and S. Enteritidis was found to be 7% prevalent. The south region of Tripoli had the highest S. Enteritidis (9%), while the west region had the highest Salmonella spp. (22%). Salmonella prevalence increased significantly (p < 0.01) higher in the spleen (13%) as compared with the crop (5%) and neck (7%). Based on bacterial resistance pattern, Salmonella spp. isolated from the spleen had the highest multiple antibiotic resistance (MAR) index of 0.86 in the south region followed by MAR indexes of 0.8 and 0.46 in the West and East, respectively. Conclusion: Isolation of Salmonella from the spleen may indicate chickens' systemic infection and failure to control the most important microbe for public health. Thus, the control measures have to be revised and a national Salmonella control program should be put in place urgently.

Results of the eighteenth winter waterbird census in Libya in 2022.

Background: Libyan wetlands are diverse; the coastline of Libya, in particular, has different kinds of wetlands, such as salt marshes, bays, lakes, lagoons, and islands. These varieties in habitats provide good shelters and foraging sites for migratory birds during their journeys between Eurasia and Africa. Since the beginning of the Libyan winter census of waterbirds International waterbirds census (Libya IWC) in 2005, which continued regularly until 2012, it has had relatively the same performance in the number of covered sites. However, since 2013, due to the security situation that Libya has experienced due to wars and conflict, which negatively affected the quality of the IWC in Libya, the number of sites has dramatically decreased, reaching only six locations during the middle of the previous decade. Aim: The IWC 2022 aimed to count the birds along the Libyan coast from January 10 to 29. Methods: The census activities were conducted from dawn to dusk during the study period by using high-quality Telescopes, binoculars, and digital cameras for the documentation. Point transects method was used to cover the sites. Results: The results of this year showed that a total of 64 sites were covered, and 68 species of waterbirds were counted, with an abundance of 61,850 individuals. During the census period, a total of 52 non-waterbird species found in Wetlands were recorded, and the number of individuals was 14,836 birds. A total of 18 threatened species were observed during this survey, 12 of them are mentioned in the International Union for Conservation of Nature Red List, and nine species are mentioned in the regional activities center of specially protected areas annex II as threatened in the Mediterranean, where the species; Larus audouinii (Payraudeau, 1826), Larus genei (Breme, 1839), and Puffinus yelkouan (Acerbi, 1827) are mentioned in both of them. Conclusion: The lack of the number of ornithologists and bird watchers is still one of the factors affecting the quality of the IWC in Libya, as well as lack of funding remains an important factor that plays a major role in the success of the waterbirds census.

Pathological lesions associated with Vibrio infection in Atlantic horse mackerel (Trachurus trachurus L., 1758) from the western coast of Tripoli, Libya.

Background: Vibrios are aquatic bacteria causing Vibriosis in humans and aquatic animals. Vibriosis is a significant disease of cultured and wild fish. Aim: The present study aimed to address the impact of Vibrios on the health status of Trachurus trachurus inhabiting the coastal area of Tripoli. Methods: A total of 100 samples of (T. trachurus) were collected randomly from the Western Coast of Tripoli and Bab Al-Baher market, throughout the period from spring 2019 to summer 2019. All the sampled fish were examined externally and internally and lesions were recorded. Bacterial isolation from the liver and kidney was carried out using the appropriate culture media. Tissue samples were taken from the liver, kidney, and spleen in 10% neutral buffered formalin for a histopathology examination. The tissue sections were stained with hematoxylin and eosin to assess morphologically and Perl's Prussian blue for the demonstration of ferric iron. Results: On average 69% of the infected fish exhibited at least one pathological lesion. Vibrios were recovered from 90% of the examined fish. The histopathological changes of the liver showed severe congestion of blood vessels (BVs), mononuclear cell infiltration surrounding a bile duct, granular degeneration and coagulative necrosis of hepatocytes in the centrilobular area, marked vacuolar degeneration of hepatocytes, activation of melano-macrophage centers (MMCs), multiple cysts of nematode in hepatic tissue (incidental finding). The histopathological alterations of the kidney showed severe congestion of BVs, vacuolar degeneration of the renal tubular epithelium, severe interstitial mononuclear cell infiltration, and marked activation of MMCs in the kidney. Moreover, congestion of BVs and marked activation of melano-macrophages (MMCs) were found in the spleen. The MMCs of most of the sampled tissues showed a strong positive reaction for ferric iron. Conclusion: The polluted aquatic environment by sewage at Tripoli Coast is an essential factor for triggering the pathogenicity and invasion of Vibrios to vulnerable Atlantic horse mackerel. Also, this study is a preliminary step to give a baseline for further future studies on epidemiology and control of Vibrio infection in Libyan fish.

Surveillance of the spread of avian influenza virus type A in live bird markets in Tripoli, Libya, and determination of the associated risk factors.

Background and Aim: Studies on avian influenza virus (AIV) in Libya are few and limited. This study aimed to determine the presence of AIV in live bird markets (LBMs) in Tripoli and determine the risk factors associated with AIV spread . Materials and Methods: In total, 269 cloacal swabs were randomly collected from different bird species in 9 LBMs located in Tripoli and its surrounding regions. The target species were ducks, geese, local chickens, Australian chickens, Brahma chickens, turkeys, pigeons, quails, peacock broiler chicks, and pet birds. Total RNA was extracted from the swab samples and used for real-time polymerase chain reaction to detect AIV type A. Results: Of the 269 samples, 28 (10.41% of total samples) were positive for AIV type A. The LBMs with positive samples were Souq Aljumaa, Souq Alkhamees, Souq Althulatha, and Souq Tajoura. The highest percentage (35.71%) of AIV was recorded in Souq Aljumaa. Positive results for AIV type A were obtained primarily in three species of birds: Ducks (14/65; highest percentage: 21.5%), local chickens (12/98; 12.24%), and geese (2/28; 7.14%). Furthermore, the following three risk factors associated with the spread of AIV type A were identified: Time spent by breeders/vendors at the market (odds ratio [OR] = 11.181; 95% confidence interval [CI] = 3.827-32.669), methods used for disposing dead birds (OR = 2.356; 95% CI = 1.005-5.521), and last visited LBM (OR = 0.740; 95% CI = 0.580-0.944). Restricting the movement of poultry vendors from one market to another may protect against AIV spread. Conclusion: The findings of this study indicate the high risk of AIV spread in LBMs and highlight the need for continuous surveillance of LBMs across the country.

Seroprevalence and molecular detection of Newcastle disease virus in backyard chickens in Tripoli, Libya.

Background: Newcastle disease (ND) is a viral disease that affecting many avian species all over the world. Aim: ND has been successfully controlled by the vaccination of commercial poultry in Libya. However, there was a lack of information about the situation of ND in backyard chickens. Therefore, this study determined the prevalence of ND in backyard chickens in different locations of Tripoli. Methods: A total number of 280 cloacal swabs (190 in summer and 90 in winter) and 412 sera were collected from non-vaccinated backyard chicken flocks in different geographical locations within the area of Tripoli namely Qasr Ben Ghashier, Al-Sawani, Souq Al-Gomaa, Tajourah, Ein Zara, and Janzour. Cloacal swabs and sera were tested by real time polymerase chain reaction (PCR) and ELISA, respectively. Results: The prevalence of ND virus (NDV) infection in backyard chickens in different locations of Tripoli during summer and winter was 45% using real-time reverse transcription-PCR. Except in Qasr Ben Ghashier, the prevalence in summer season was significantly higher than in winter (X2 = 46.13, p ≥ 0.00001). ELISA test revealed 218 positive out of 412 tested samples with total prevalence of 53% across the city of Tripoli in all regions. Obviously, Qasr Ben Ghashier had significantly (X2 = 74.09, p ≥ 0.00001) the highest prevalence (82%) of NDV specific antibodies followed by Tajourah (68%). Conclusion: This study demonstrated the situation of ND in backyard chicken highlighting the necessity of a comprehensive vaccination plan for backyard chickens.

Molecular detection and characterisation of avian paramyxovirus type 1 in backyard chickens and pigeons in Alzintan city of Libya.

Avian paramyxovirus-1 (APMV-1) is the causative agent of Newcastle Disease which affects many species of birds leading to high mortality and heavy economic losses among poultry industry worldwide. Newcastle disease is endemic in Libya with frequent outbreaks occurring in commercial and backyard poultry. APMV-1 was isolated and characterised during the outbreak in 2013. In current study, we report another Newcastle disease outbreak that emerged in backyard chickens and pigeons in Alzintan city on March 2015. Two viruses were detected in cloacal swabs from backyard chickens, namely APMV-1/Libya/15VIR5368/2015 and APMV-1/Libya/15VIR5371/2015. Genetic sequencing of these viruses revealed the presence of velogenic APMV-1 belonging to genotype VIIi genetically similar to the viruses isolated on 2013. During the same period, neurologic signs and mortality were noticed in pigeons. Samples of brain tissue were tested by rRT-PCR which revealed presence of velogenic APMV-1 belonging to lineage 4A (GKKRKR*F Lin.4A) or genotype VIb. To the best of our knowledge, this is the first report of the detection and molecular characterization of APMV-1 in a pigeon in Libya. The phylogenetic analysis of the F gene showed 86% identity to isolates from Iran and Egypt. This study may indicate the circulation of APMV-1 within backyard birds and pigeons which may present a threat to commercial poultry. Considering these findings, vaccination of backyard birds and pigeons and further epidemiological studies are strongly strongly recommended.

Identification of phenolic compounds, antibacterial and antioxidant activities of raisin extracts.

In this study, antibacterial, antioxidant and phenolic compounds of raisin extracts was evaluated. Different solvent extraction methods were utilized to extract phenolic compounds from raisin. The phenolic compounds of raisin extracts was determined using HPLC and three compounds were found, catechin, quercetin and rutin. The antibacterial activity of the acetonic extract was tested against four bacterial pathogens viz. Staphylococcus aureus, Pseudomonas aeroginosa, Salmonella typhimurium and Escherichia coli using both disk diffusion and minimum inhibitory concentration (MIC) methods. The acetonic extract exhibited the highest activity against Staphylococcus aureus with zone of inhibition of 14mm and the MIC of 25 mg/ml. However, there was a little activity against E. coli and S. typhimurium. The methanolic extract showed good antioxidant activity as indicated by 2,2-diphenyl-1-picrylhydrazyl free radical assay (DPPH). In conclusion, raisin contains potent phenolic compounds and their application might function as promising natural preservative and antimicrobial agents in food industry and also good antioxidant food that helps to minimize the risk of degenerative diseases.

Biosecurity and geospatial analysis of mycoplasma infections in poultry farms at Al-Jabal Al-Gharbi region of Libya.

Geospatial database of farm locations and biosecurity measures are essential to control disease outbreaks. A study was conducted to establish geospatial database on poultry farms in Al-Jabal Al-Gharbi region of Libya, to evaluate the biosecurity level of each farm and to determine the seroprevalence of mycoplasma and its relation to biosecurity level. A field team of 7 Veterinarians belongs to the National Center of Animal Health was assigned for data recording and collection of blood samples. Personal information of the producers, geographical locations, biosecurity measures and description of the poultry farms were recorded. The total number of poultry farms in Al-Jabal Al-Gharbi Region is 461 farms distributed in 13 cities. Out of these, 102 broiler farms and one broiler breeder farm (10 houses) which were in operation during team visit were included in this study. Following collection of blood, sera were separated and tested by Enzyme-linked immunosorbent assay (ELISA) for the presence of antibodies against Mycoplasma (General antigen for M. gallisepticum and M. synoviae). The seroprevalence of Mycoplasma in the region was 28% (29 poultry farms out of 103 were infected). About 50% (23 out of 47) of poultry farms located in Garian city were infected with Mycoplasma and one significant cluster of Mycoplasma infection in the city was identified. Low level of biosecurity was found in poultry farms of the region. Out of the 103 farms included, 63% of poultry houses has a ground of soil and 44% of them has uncoated walls which may influence the proper cleaning and disinfection. Almost 100% of the farms are at risk of exposure to diseases transmitted by wild birds such as avian influenza and Newcastle disease due to absence of wild birds control program. Although, 81% of the farms have entry restrictions, only 20% have disinfectants at entry which increase the risk of exposure to pathogens. The results of this study highlight the weakness points of biosecurity measures in poultry farms of Al-Jabal Al-Gharbi region and high seroprevalence of mycoplasma. Data collected in this study will assist the Veterinary authorities to apply effective disease control strategies.

Exploiting serological data to understand the epidemiology of foot-and-mouth disease virus serotypes circulating in Libya.

Sporadic outbreaks of foot-and-mouth disease (FMD) have occurred in Libya for almost fifty years. During the spring of 2013, a countrywide serosurvey was undertaken to assess the level of FMD virus circulation and identify FMD virus serotypes in the country. A total of 4221 sera were collected, comprising samples from large ruminants (LR; n=1428 samples from 357 farms) and small ruminants (SR; n=2793 samples from 141 farms). FMD sero-prevalence of NSP antibodies determined by ELISA were 19.0% (271/1428) with 95% CI (16.9 - 21.0) and 13.5% (378/2793) with 95% CI (12.3 - 14.8) for LR and SR samples, respectively. The sero-prevalence of NSP antibodies in LR was 12.3% and 19.8% for age group < 1 year and ≥ 1 year, respectively (X2= 4.95, P= 0.026), while in SR was 3.7%, 13.6% and 21.3% for age group < 1 year, 1-2 year and > 2 year, respectively (X2= 118.1, P= 0.000). These observed NSP serologic profiles support the hypothesis of an endemic level of FMD circulation in Libya. All positive sera were tested for SP antibodies for O, A and SAT-2 FMD virus serotypes. Serotype O was the dominant circulating serotype followed by serotype A, while evidence of SAT-2 was not found. These data provide an insight into the wider epidemiology of FMD in Libya, and contribute to field and laboratory investigations that during 2013 serotype O (O/ME-SA/Ind-2001 lineage) was isolated from clinical samples collected from the country.

Characterization of Avian Influenza and Newcastle Disease Viruses from Poultry in Libya.

On March 2013, the Libyan poultry industry faced severe outbreaks due to mixed infections of APMV-1 (Newcastle disease) and low pathogenic avian influenza (AI) of the H9N2 subtype which were causing high mortality and great economic losses. APMV-1 and H9N2 were isolated and characterized. Genetic sequencing of the APMV-1/chicken/Libya/13VIR/ 7225-1/2013 isolate revealed the presence of a velogenic APMV-1 belonging to lineage 5 (GRRRQKR*F Lin.5) or genotype VII in class II, according to the nomenclature in use. Three AI viruses of the H9N2 subtype, namely A/avian/Libya/13VIR7225-2/2013, A/avian/Libya/13VIR7225-3/2013, and A/avian/Libya/13VIR7225-5/2013, were isolated and found to belong to the G1 lineage. Analysis of amino acid sequences showed that the analyzed H9N2 viruses contained the amino acid Leu at position 226 (H3 numbering) at the receptor binding site of the HA, responsible for human virus-like receptor specificity. On March 2014, an outbreak of highly pathogenic avian influenza (HPAI) virus of the H5N1 subtype was diagnosed in a backyard poultry farm in an eastern region of Libya. The H5N1 isolate (A/chicken/Libya/14VIR2749-16/2014) was detected by real time RT-PCR (rRT-PCR). Genetic characterization of the HA gene revealed that the identified subtype was highly pathogenic, belonged to the 2.2.1 lineage, and clustered with recent Egyptian viruses. This study revealed the presence of a velogenic APMV-1 genotype and of two influenza subtypes, namely HPAI H5N1 and H9N2, which are of major interest for public and animal health. Considering these findings, more investigations must be undertaken to establish and implement adequate influenza surveillance programs; this would allow better study of the epidemiology of APMV-1 genotype VII in Libya and evaluation of the current vaccination strategies.