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This study was designed to evaluate haematological response between Nigerian indigenous pigs (NIP) and Large White x Landrace crossbred pigs (LWL) when vaccinated with sheep RBC. Twenty male pigs with average age of 42 ± 3 days and weighed 3.10 ± 0.29 kg (NIP) and 6.90 ± 0.43 kg (LWL), were used. They were assigned to groups A (10 NIP) and B (10 LWL); each was further divided into two with five animals in each replicate. Processing of sheep RBC followed standard procedures; feed and animal management were similar. All the pigs were vaccinated with1 ml of 10 % sheep RBC per pig at week 4 and revaccinated 3 weeks later. Their haematological profiles were determined using standard procedures and the study lasted ten weeks. There was a rise in WBC count of both groups after initial vaccination. Mean WBC count of LWL was significantly (p ≤ 0.05) higher at weeks 0, 1, 4 and 6, respectively. Lymphocyte count of the two groups also increased sharply after initial vaccination; values recorded for LWL showed a slight but a continuous rise while those of the NIP generally decreased and increased in value. A significant differences in mean values of neutrophil were recorded prior to initial vaccination (p = 0.011, t = 8), on weeks 1 (p = 0.013, t = 8) and 3(p = 0.005, t = 8) with NIP maintaining higher values than LWL. There was no significance (p ≥0.05) difference in the mean values of eosinophil, basophil and monocytes for both groups.

One hundred and ten Isa Brown layers were vaccinated with La Sota, once at point of lay at 18 weeks and three times at peak of lay which occurred at 27–29 weeks of age. Thereafter, they were weekly monitored for haemagglutination inhibition (HI) antibody decline. The first batch A of the layers were challenged with velogenic viscerotropic Newcastle disease (vvND) virus (vvNDV) on day 24 post‐vaccination (PV), when the geometric mean titre (GMT) was 84.4, batch B were challenged on day 48 PV at GMT of 42.2, while batch C were challenged on day 97 PV at GMT of 21.1. The individual chicken HI antibody titres of the 10 layers in batch C at the day of challenge were: 7 layers had HI titres of 16, 2 layers had HI titres of 32 and 1 layer had HI titres of 64. Each challenge in the three batches produced no clinical signs including drop in egg production. But there was initial swelling of the spleen followed by atrophy with high antibody responses. The virus was recovered in all the cloacal swabs on days 3–9 post‐challenge (PC) at low titres. On days 145 PV and 48, post‐Batch C challenge the remaining hyperimmunized unchallenged layers demonstrated a drop in total % egg production (p, Based on this observations, it is concluded that triple La Sota vaccination can solidly protect layers against drop in egg production in areas where vvNDV infection is enzootic.

This study investigated the immune responses to La Sota vaccination, used in protection of chickens against Newcastle disease, in light weight type breeds of chickens (pullets) and heavy weight type breeds of chickens (broilers) used in commercial poultry production. Seven‐week‐old 50 White Marshall broilers (Br) and 50 Isa Brown pullets (Pu) were randomly divided into four groups: vaccinated broilers chickens; (VBr), unvaccinated broiler chickens (UBr), and vaccinated pullet chickens (VPu) and unvaccinated pullet chickens (UPu). Chickens in groups VBr and VPu were vaccinated with La Sota vaccine, whereas groups UBr and UPu were not vaccinated. On day 0 post vaccination (PV), six chickens from group Br and Pu, and on day 4 PV, three chickens from each four groups were sacrificed and the bursa weight index (BWI), thymus weight index (TWI) and the splenic weight index (SWI) were obtained. The chickens were observed for clinical signs and lesions. Serum samples were collected from the chickens in all the groups on days 0, 7, 14, 21, 28 PV and assayed for haemagglutination inhibition (HI) antibodies. The BWI, TWI and SWI were 0.37 ± 0.05, 0.35 ± 0.17, 0.65 ± 0.26 for pullets and 0.11 ± 0.04, 0.13 ± 0.02, 0.36 ± 0.17 for broilers on day 0 PV. On day 4 PV there was no significant difference (p, La Sota vaccination, used in protection of chickens against Newcastle disease, did not produce clinical signs or lesions in vaccinated broiler and pullet chickens, however, pullets produce higher antibodies than broilers because of their higher bursa weight index. The above observations show that naturally pullets produce higher antibodies than broilers because of their higher BWI. More work needs to be done using other breeds of pullets and broilers to confirm this observation.

Newcastle disease (ND) is a major problem of poultry production worldwide. Control is by biosecurity and vaccination. In this project, we studied the pathology of Komarov vaccine which is commonly used in many countries of Africa on the Hitchner B1 (HBI) vaccinated and unvaccinated broilers. Seventy-five Arbor Acres broilers were obtained at 1 day old. Twenty-five of the broilers were given HB1 vaccine at the hatchery and Komarov vaccine at 5 weeks of age (group HK). A second group of 25 broilers were given only Komarov vaccine at 5 weeks of age (group K). The third group remained as unvaccinated (UU). All the groups were observed for clinical signs and lesions. Depression, sneezing, coughing and noisy respiration were observed in group K broilers from day 2 post Komarov vaccination (PKV). Leg paralysis occurred in 6 broilers on day 8 PKV. The clinical signs were milder in the HK broilers. Only one broiler showed leg paralysis in this group on day 18 PKV. No mortality occurred in the three groups. The bursa, spleen and thymus showed mild to moderate enlargement, atrophy and depletion of lymphocytes on days 3, 5, 8 and 14 PKV in HK and K groups. The trachea and lungs were congested. The haemagglutination inhibition (HI) antibody titres in the K group were higher than those of HK and UU groups on days 7, 24 and 21 PKV. The above observations show that Komarov vaccine may cause no mortality in vaccinated and unvaccinated broilers and higher HI antibodies are produced in broilers that have not been vaccinated earlier.

Salmonellosis is a serious medical and veterinary problem worldwide and causes great concern in the food and livestock industries, especially the poultry industry which occupies a prominent position in the provision of animal protein and accounts for about 25% of local meat production in Nigeria particularly and is identified as a disease of major economic importance causing low performance in poultry production. The study was carried out at the experimental animal farm, Faculty of Veterinary Medicine, University of Nigeria, Nsukka, Nigeria. One hundred (100) five-week old chickens obtained from the Poultry division of National Veterinary Research Institute, Vom, were used for the experiment. The birds were randomly assigned to 4 groups of 25 birds per group (A, B, C, D). Each bird in all the groups received 0.5 ml of PBS containing 1 × 108 cfu/ml of Salmonella enterica serovar Zega as follows: Group A was infected with Salmonella Zega intra-nasally (IN). Group B was infected with Salmonella Zega intra-peritonealy (IP). Group C was infected with Salmonella Zega orally (OR). Group D was the Uninfected control (CT). There was a significant change (p 0.05) in the mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) in the infected groups compared across the different days post infection. There was significant increase (p Salmonella Pullorum and Salmonella Gallinarum that are known to cause pathology in birds Salmonella Zega which is none host specific for birds can also cause pathology in them. This is the first report in the study area to the best of our knowledge.

This study investigated if increased doses of La Sota vaccine can increase antibody response to Newcastle disease without any serious adverse effect on the bursa. One hundred broilers aged four weeks were randomly assigned into four groups of 25 each: ZD, each drenched with phosphate-buffered saline, SS, DD and TD broilers were each drenched with single, double and triple dose of La Sota vaccine, respectively. The broilers were examined for signs and lesions. At weekly intervals, serum samples were collected post-vaccination (PV) and assayed for haemagglutination inhibition antibody. Groups DD and TD antibody titres were significantly (p 0.05) difference between titres of DD and TD groups. Groups DD and TD geometrical mean titres were more than two times higher than that of SD group on day 21 PV. The bursa of all the vaccinated groups appeared reduced in size, with mild depletion of lymphocytes on day 10 PV. Generally, the integrity of the bursa was intact. This suggests that doubling the dose of La Sota vaccine may be considered in improving the performance of the vaccine in the control of velogenic Newcastle disease.

Thirty-seven percent (37%) formaldehyde- possessing antimicrobial activity has been used in various forms as a fumigant for mould control and as a feed additive for feed preservation. The study evaluated the effects of formaldehyde-treated poultry feed on the immune response of birds to Newcastle disease virus (NDV) infection with Kudu 113 strain. A total of 100 chicks were acquired from Zartech Hatchery, Ibadan, Nigeria. They were randomly appropriated into A, B, C and D experimental groups, with each group containing 25 birds. Group A chicks were vaccinated, fed treated feed and infected with ND virus while group B chicks were vaccinated, fed untreated feed and infected with ND virus. Chicks in group C were not vaccinated but fed treated feed and infected with ND virus whereas chicks in group D were not vaccinated, fed untreated feed and infected with ND virus. The data generated were analysed with analysis of variance (ANOVA). Formaldehyde-treated feed had no significant effect on the PCV, antibody response to NDV, organ index and feed intake but significantly affected the body weights of the birds. Formaldehyde, despite the antimicrobial activities, may not prevent infection of Newcastle disease virus infection, when used as a feed additive.

The aim of this project was to find out the comparative susceptibilities of broilers and layer chickens to a low dose of velogenic viscerotropic Newcastle disease virus (vvNDV) infection using mortalities as the main indicator. Five weeks old Anak broilers and Lohmann Brown layer chicks were inoculated with vvNDV. The birds were monitored daily for clinical signs and disease evolution was evaluated. Clinical signs consisting of depression and diarrhea appeared at 3 days post-inoculation (DPI) in broilers and at 2 DPI in layer chickens resulting in total mortalities of 30% and 0% in broilers and layer chickens, respectively. Weight loss was statistically, significant in infected broilers on 3 to15 DPI (p 0.05). Macroscopic lesions were similar but more severe in broilers compared to layer chickens and included proventricular haemorrhages, intestinal and caecal ulcers. But atrophy of the bursa, spleen and thymus and necrosis and depletion of lymphocytes in the three organs were severe in the infected broilers and pullets Antibody response was significantly (p

The development of pelleted food–based vaccine against Newcastle disease (ND) using a thermostable NDVI2 strain in Acha (Digitalia iburua) is reported. The Acha cereal was subjected to rigorous processing of washing, soaking, boiling, roasting and grinding into fine powder prior to virus incorporation. The mixture which was passed through a locally fabricated pelleting machine resulted in fine pellets. The virus content in the pellets determined by inoculation of susceptible embryonated chicken eggs showed appreciable titres above 108 Egg Infective Dose 50% end points (EID50) per g of feed. These titres appear to be higher than the recommended minimum immunizing dose of 105.5 EID50 per ml of vaccine. Further in-vitro and in-vivo assessment of the pelleted vaccine is advocated. Key words: Pelleted, NDVI2, food vaccine, Digitalia iburua, high virus titres.

This study was conducted to compare growth performance, immunological response, and biochemical profile between local or Nigerian indigenous pigs (NIP) and exotic Large White x Landrace crossbred pigs (LWL). Twenty weanling pigs, aged six weeks were divided into groups A (NIP) and B (LWL); each group was randomly assigned into two replicates of five pigs. Feed and animal management were similar and study lasted ten weeks. Their feed and water intake, average daily weight gain (ADG), and gain: feed or feed efficiency were determined. All the pigs were vaccinated with1 ml of 10 % sheep RBC per pig at week 4 and boosted at week 7. Their antibody titres and serum biochemical profiles were determined using standard procedures. Daily feed and water intake and weight gain were significantly (p < 0.05) higher in LWL than NIP. There was no significant (p > 0.05) difference in their gain: feed but figures were higher in NIP. Although LWL had higher antibody titres at weeks 1 of initial and revaccination, NIP recorded higher titres at weeks 2, 3 and 4 of initial and 2 of revaccination, respectively. Albumin levels in both groups showed a significant (p = 0.003, t = 8) difference in their mean on week 1 following initial vaccination, their values being 4.29 ± 0.05 and 4.67 ± 0.08 g/dL for groups A and B, respectively.The NIP showed significantly (p < 0.05) higher total protein and globulin throughout the period of assay. Although the LWL grew faster and had better immediate immunological performance, the NIP recorded slightly higher feed efficiency and more sustained antibody titres post vaccination with Sheep RBC.Keywords: Swine, growth performance, serum biochemistry, sheep RBC, antibody titres

This study compared the immunomodulatory effects of methanolic leaf ex-tract of Moringa oleifera and Vacci-Boost® in chickens experimentally chal-lenged with velogenic Newcastle Disease virus (vNDV) strain. One hundred 21 days old chicks were randomly divided into five equal groups designated A, B, C, D and E. Groups B and D were given 200mg/kg dose of M. oleifera extract from day 21 to day 35 of age in drinking water while group C was treated once with Vacci-Boost® during vaccination on day 21 of age accord-ing to the manufacturer’s instructions. Groups A, C and D chicks were vac-cinated on day 21 of age with Newcastle disease (ND) vaccine La Sota while groups B and E were not vaccinated. All the groups were challenged on day 35 of age. Haemagglutination Inhibition titer, relative organ weights, body weight and Packed Cell Volume were assessed. On days 28 and 35, HI titer of the immunomodulators supplemented groups were significantly (p ≤ 0.05) higher than those of the unsupplemented groups. The relative weights of the lymphoid organs of the supplemented groups were significantly (p ≤ 0.05) higher than those of the unsupplemented group. Also, Vacci-Boost® supple-mented group had higher mean body weight although they were not signifi-cantly (p ≥0.05) higher than those of the unsupplemented groups. There were no significant (p ≥ 0.05) differences in the body weight of the M. oleif-era treated and those of untreated groups.

In recent years Nigeria has experienced sporadic incursions of highly pathogenic H5N1 avian influenza among poultry. In 2008, 316 poultry-exposed agricultural workers, and 54 age-group matched non-poultry exposed adults living in the Enugu or Ebonyi States of Nigeria were enrolled and then contacted monthly for 24 months to identify acute influenza-like-illnesses. Annual follow-up sera and questionnaire data were collected at 12 and 24 months. Participants reporting influenza-like illness completed additional questionnaires, and provided nasal and pharyngeal swabs and acute and convalescent sera. Swab and sera specimens were studied for evidence of influenza A virus infection. Sera were examined for elevated antibodies against 12 avian influenza viruses by microneutralization and 3 human viruses by hemagglutination inhibition. Four (3.2%) of the 124 acute influenza-like-illness investigations yielded molecular evidence of influenza, but virus could not be cultured. Serial serum samples from five poultry-exposed subjects had a ≥4-fold change in microneutralization titers against A/CK/Nigeria/07/1132123(H5N1), with three of those having titers ≥1:80 (maximum 1:1,280). Three of the five subjects (60%) reported a preceding influenza-like illness. Hemagglutination inhibition titers were ≥4-fold increases against one of the human viruses in 260 participants. While cross-reactivity from antibodies against other influenza viruses cannot be ruled out as a partial confounder, over the course of the 2-year follow-up, at least 3 of 316 (0.9%) poultry-exposed subjects had evidence for subclinical HPAI H5N1 infections. If these data represent true infections, it seems imperative to increase monitoring for avian influenza among Nigeria's poultry and poultry workers.

The determination of optimum reaction temperature and time for biodiesel yield from Coconut (Cocos nucifera) oil was studied. The oil was transesterified using potassium hydroxide (KOH) in methanol as catalyst to obtain the crude biodiesel. For the reaction time, the biodiesel production was carried out at 30 min, 45 min, 60 min, 75 min and 90 min while their temperature (60oC), oil to alcohol ratio (6:1) and catalyst concentration (0.65%) were kept constant. For the reaction temperature, the reaction was carried out at 45oC, 50oC, 55oC, 60oC and 65oC, while their reaction time (60 min), oil to alcohol ratio (6:1) and catalyst concentration (0.65%) were kept constant. The crude biodiesel were purified by washing with water severally to obtain the relatively pure biodiesel. They were dried using solar dryer for a period of four (4) days to obtain moisture-free pure biodiesel. They were subsequently analyzed for various parameters; Kinematic viscosity, acid value, free fatty acid (FFA), specific gravity, iodine value, ash value and flash point. The different Original Research Article International Research Journal of Pure & Applied Chemistry, 4(1): 108-117, 2014 109 variants gave results of the parameters analyzed comparable to International standards of biodiesel (ASTM) methods. The results of the study showed that for the reaction time, the optimum yield was obtained at 45 min giving a biodiesel yield (after purification) of 88% while for the reaction temperature, the optimum yield was obtained at 45oC with a biodiesel yield of 87.4%. General results obtained showed that the optimum yield of biodiesel obtainable from Coconut oil when transesterified using KOH/methanol is about 88%. Overall results indicate that Coconut oil can serve as a veritable feedstock for biodiesel production.

The effect of velogenic Newcastle disease virus (vNDV) on the immune responses and serum proteins was investigated in six-week-old ducks and chickens. Results showed that weight loss was markedly significant (p

The hematological lesions consequent upon velogenic Newcastle disease virus (NDV) infection were investigated in 6-week-old ducks and chickens. Following intramuscular inoculation, the results indicated significantly lower (p

This paper reports on recurring outbreaks of fowl pox in a particular pen present in a poultry farm located at Nsukka, Southeast Nigeria. The outbreaks were seen in one batch of white cockerel and two batches of brown layers. Reduced egg production, weight loss, nodular lesions on the combs, wattles and eyelids, and diphtheritic lesions in the mucous membranes of the oral cavity characterized the disease. At post mortem, a characteristic whitish cheesy material conforming to the shape of the cornea was common in the severe outbreak in layers, but absent in the cockerels and the mild outbreak in layers. No bacteria were isolated from the matrix of the cheesy material while Staphylococcusaureus and Escherichia coli were isolated from the surface of the cheesy material and the ocular swab. The report also showed the importance of vaccination in control of the disease. There was enteritis and soiled vents in the cases examined. Biosecurity measures combined with vaccinations were suggested indispensible for the control of the disease in Nigeria.

This study was aimed at evaluating the immune boosting potential of crude methanolic extract of Moringa oleifera in chickens experimentally challenged with Newcatle disease (ND) virus.One hundred and twenty forty two (42) day old chicks were randomly divided into four equal groups. Groups I and II were given daily oral treatment of methanolic extract of M. oleifera at 200 mg/kg body weight until day 56 of age. Groups II and III were vaccinated with the La Sota strain of ND vaccine. Group I was not vaccinated while group IV was left as untreated/unvaccinated control. All the groups were challenged with the velogenic strain of ND virus (VNDV) on day 56. Following challenge, the birds were assessed for cellular and humoral immune responses. Data on cellular and humoral immune responses were analysed using the statistical package for social sciences (SPSS). Increases in total and differential cell numbers and haemagglutination inhibition (HI) titre in the extract-treated groups did not correlate with total protection against ND. M. oleifera extract increased ND HI titre and the total and differential leukocyte counts in the treated and unvaccinated group I birds much more than those of treated and vaccinated group II birds, hence it could be recommended as a prophylactic treatment against ND in non vaccinated birds. Key words: Velogenic Newcastle disease, chickens, Moringa oleifera, immunity.

Two hundred and fifty (250) white cockerels were used to compare the differences between the intraocular and oral routes of administration of ND vaccine La Sota in adult chickens. At 20 weeks of age, serum samples were collected from the chickens and used to estimate the antibody levels against Newcastle disease virus using heamagglutination inhibition (HI) test. The birds were randomly divided into two groups, G1 and G2. Birds in G1 were vaccinated with ND vaccine La Sota intraocularly while birds in G2 were vaccinated orally. Serum samples were collected from chickens in the two groups weekly and used to estimate the HI antibody. Result showed higher antibody level in the chickens vaccinated intraocularly when compared with those vaccinated orally. There was significant difference (p < 0.05) between the geometric HI titres of chickens in the two groups on days 7, 14 and 28 PV but it did not differ significantly on day 21 PV. Challenge studies showed 100% protection of chicken in the two groups on day 21 PV. We identified Harderian glands' possible roles in producing local and humoral immunity in intraocular vaccinations and the destruction of some of the vaccinal viruses by gastric secretions in oral vaccinations as the possible reasons for the production of higher antibodies in intraocular vaccination in adult chickens.

This project was undertaken to study the immunosuppressive capabilities of velogenic viscerotropic pathotype of Newcastle disease virus (VVNDV) infection in cockerels. Two hundred six-week-old cockerels were divided into four groups. Groups B/VUC and C/VC were vaccinated with LaSota in drinking water at 6 weeks of age. Groups C/VC and D/UC were challenged with VVNDV at 8 weeks of age. Three days post challenge (PC), the cockerels in group D/UC came down with clinical signs which included depression and greenish diarrhoea. Total mortality was 74.6 %. The C/VC cockerels showed no clinical signs. But both challenged groups showed significant weight loss, significant loss of total serum proteins, globulin and albumen (P

4 Abstract: The study was carried out to assess the Haemagglutinin thermostability of Newcastle disease virus isolates obtained from wild birds in three climatically distinct states in central Nigeria. Identification of heat stable ND virus isolates from the locality will provide environmentally friendly thermostable vaccine candidates for rural poultry. The 12 field virus isolates and the 5 vaccine virus strains showed variable degrees of heat stability. Three field isolates each was inactivated in 5 min, three in 10 min and one in 15 min. One isolate was inactivated in 20 min while two and three strains got inactivated in 25 and 30 mi n respectively. The most thermostable of the field isolates was inactivated in 40 min. A more thermostable clone was subsequently derived from the latter strain as a local vaccine candidate. For the vaccine strains, NDV (I/O) and NDV (K) were inactivated in 20 min while NDV (L) was inactivated in 25 min. The velogenic strain (Herts) was inactivated in 40 min. The two established thermostable strains, NDV4 and NDVI2 were inactivated in 90 min each. The thermostable profile of the field virus strains did not vary with the climatic background of the isolates.

Thirty (30) vials of Newcastle Disease (ND) vaccine. La Sota were procured locally and tested for potency when stored under conditions of irregular power supply. The vaccines were of the same batch and were eighteen months to the expiration time. The potency of the vaccines was tested using Haemagglutination (HA) test before storage. The vaccines’ immunogenicity was determined in a batch of 250, 3 weeks old white cockerels after which the vaccines were stored in the refrigerator with two-third of the storage period at 0-4 C and the remaining one third at room temperature of 26-30 C. During the study, the o o methods of vaccine storage were alternated frequently to reflect the frequent power outages. The humoral immune response of the vaccinated chickens was estimated by Haemagglutination Inhibition (HI) test. The potency of the vaccines was tested on days 28, 56, 84, 112 and 140 post storage. On day 140, another batch of 250, 3 weeks old white cockerels were vaccinated with a vial from the stock and the humoral immune response of these chickens was evaluated at 3 weeks post vaccination. The mean HA titre of the vaccine before storage was 128, while the mean HA titres of the vaccines after storage (i.e., day 140) was 8. The mean HI titres of the vaccinated chickens before and after storage were 1005.7 and 8.3, respectively. Student t test was used to compare the mean HI titre of the chicken vaccinated prior and at the end of vaccine storage. The GMT mean HI titre of the chickens vaccinated prior to storage was significantly (p

This study investigated the haematological changes in vaccinated and unvaccinated laying chickens experimentally infected with a velogenic Newcastle disease virus. Two hundred and forty laying chickens were randomly assigned into four groups of 60 each: vaccinated with Newcastle disease vaccines and infected with velogenic Newcastle disease virus (VI), vaccinated uninfected (VU), unvaccinated infected (UI), unvaccinated uninfected (UU). At peak production, 32-weeks-old, groups VI & UI were each inoculated intramuscularly with 0.2 ml of velogenic Newcastle disease virus. The changes in the blood cells were assayed in the groups on the specified days. The total red blood cell count (RBC) was significantly (P 0.05) differences between the PCV, RBC and HbC in VI & VU groups from day 0 to 21 PI. The leukogram showed significant (P < 0.05) differences in leukocytosis on days 3 & 6 PI followed by significant (P < 0.05) leukopenia on days 10, 15 & 21 PI in UI group. However, significant leukocytosis on day 10 PI followed by leukopenia on day 15 PI were recorded in VI group. These findings suggest that leukocytosis in UI & VI and decreased haemogram in UI are features of Newcastle disease in laying chickens. Keywords: Experimental infection, Haematology, Laying chickens, Leukocytosis, Newcastle disease

Newcastle Disease (ND) is an important disease of poultry worldwide. Its economic impact is high because mortality may reach 100% in affected poultry farms. This study was aimed at evaluating the protective properties of crude methanolic extract of Moringa oleifera in chickens. Forty two-day old chicks were randomly divided into four groups: I, II, III and IV. Groups I and II were given daily oral treatment of methanolic extract of M. oleifera at 200 mg/kg body weight until day 56 of age. Groups II and III at 42 days of age were vaccinated with the La Sota strain of ND vaccine. Group I was not vaccinated, while IV was left as untreated/unvaccinated control. All the groups were challenged with the velogenic strain of ND virus on day 56 of age. Feed intake and weight gain were evaluated. Following challenge, the birds were monitored for clinical signs, morbidity and mortality. Results of feed intake and weight gain were analysed using the statistical package for social sciences (SPSS). Survival was 0, 32, 88 and 100% in groups IV, I, II and III animals, respectively.Therefore, M. oleifera can protect birds from ND and can be used prophylactically against ND. Key words: Velogenic Newcastle disease, chickens, Moringa oleifera, morbidity, mortality.

Newcastle disease (ND) is endemic in Nigeria and constitutes a major problem to poultry production especially commercial egg production. Despite vaccination of birds, some farmers and other stakeholders still believe that there is shortened protection interval between vaccinations leading to frequent outbreaks. This work studied the antibody profile in vaccinated birds using Newcastle disease vaccine, La Sota (NDVL) with a view to establishing the rise and decline in antibody titre after vaccination and thereby determining the protection interval in our local environment. Two hundred and eighty (280) Shaver brown layers at 78% hen house production were used for the experiment. When their antibody levels were at Geometric Mean Titre of 12.1, they were vaccinated with NDVL through the oral route. On a monthly basis, the antibody titre was determined and 80 birds were taken to a distant location and challenged with a velogenic strain of Newcastle disease virus (NDV). Results showed good protection at 4 weeks, fair protection at 8 weeks and no protection at 12 weeks post vaccination (PV). We therefore recommend that under the Nigerian condition, laying flocks should be revaccinated at 7-8 weeks interval with NDVL.

Eleven multiresistant Escherichia coli strains of animal and human origin were assayed for the presence of antimicrobial resistance genes, integrons and associated gene cassettes, as well as plasmid content. Ciprofloxacin-resistant strains were screened for amino acid changes in GyrA and ParC proteins. The E. coli strains were found to harbor a variety of genes including cmlA, aac (3)-II, aac (3)-IV, aadA, strA-strB, tet (A), tet (B), bla(TEM), sul1, sul2 and sul3. Four of the eight int I1-positive strains were also positive for qacE Δ1 -sul1 region and the following gene cassettes were detected: dfrA7, dfrA12 + orfF + aadA2 and bla(OXA1)+ aadA1. Five strains contained class 1 integrons lacking the qacE Δ1 -sul1 region and they showed a single type of gene cassette arrangement (estX + psp + aadA2 + cmlA + aadA1 + qacH + IS440 + sul3). The two int I2-positive strains carried the same type of gene cassette arrangement (dfrA1 + sat + aadA1). The seven ciprofloxacin-resistant E. coli strains exhibited a Ser-83-Leu substitution in GyrA protein and a Ser-80-Ile substitution in ParC protein; six of these strains presented an additional substitution in GyrA (Asp-87-Gly or Asp-87-Asn) and one strain in ParC (Glu-84-Gly). Eight different plasmid-replicon-types were detected among the 11 E. coli strains, IncF being the most frequent one detected, found in nine strains; other plasmid replicon types detected were IncX, IncI1, IncY, IncW, IncFIC, IncB/O, and IncK. Antimicrobial resistance in the E. coli strains studied was mediated by a variety of genes, some of them included in integrons, as well as by mutations gyr A and par C genes.

As propriedades antigênicas de treze isolados do vírus da doença de Newcastle foram comparados com amostras La Sota. Usando uma das fórmulas previamente reconhecidas, significantes diferenças antigênicas foram observadas e marcantes atividades inibitórias foram percebidas entre os isolados e seus soros hiperimunes, bem como das amostras La Sota. As implicações destas diferenças para a epidemiologia e controle da Doença de Newcastle na Nigéria são discutidos.