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1.
The aim of this project is to study the clinical signs and lesion of velogenic Newcastle disease (vND) in commercial turkeys, and also to find out if La Sota vaccination offered protection against these signs and lesions. The cockerels were included as positive controls. One hundred and twenty turkey poults and cockerels were divided into eight groups as follows: unvaccinated unchallenged turkeys (UUT), unvaccinated challenged turkeys (UCT), vaccinated unchallenged turkeys (VUT), vaccinated challenged turkeys (VCT), and along the same lines, the cockerel groups were UUC, UCC, VUC and vaccinated challenged cockerels (VCC). Vaccination was at 3 weeks of age while challenge was at 6 weeks of age. The unvaccinated turkeys and cockerels (UCT and UCC) showed different degrees of depression, diarrhoea and later paralysis at challenge. Total mortality was 100% in cockerels within 6 days, but 60% in turkeys. Similar but milder clinical signs were found in the VCC with a total mortality of 13.3%. The VCT showed mild drop in feed and water consumption, and no mortality. All the challenged groups had significant (p < 0.05) loss of weight when compared with their controls. Necropsy showed that while the UCC had severe proventricular haemorrhages, intestinal and caecal tonsil ulcers, the UCT had no digestive tract lesion. There was severe atrophy of the lymphoid organs in all the challenged groups. Histopathological sections of the bursa, spleen and thymus in all the challenged groups with special emphasis on the vaccinated and unvaccinated turkeys with mortalities of 0 and 60%, respectively, had very severe necrosis and depletion of the lymphoid tissue. Virus was isolated from the cloacal swabs. The haemagglutination inhibition antibodies were significantly higher (p < 0.05) in the challenged groups than the unchallenged. The above observations in the intestinal tracts of UCT are of diagnostic significance while the gross and microscopic lesions in the UCT and VCT show that La Sota vaccination may not protect turkeys against the destruction of the lymphoid organs by vND as earlier reported in chickens. This may lead to immunosuppression and production problems in areas where vND is enzootic.  相似文献   
2.
Arrested development of Haemonchus, Cooperia and Trichostrongylus spp. was studied in (1) 14 naturally infected and eight experimentally infected West African Dwarf (WAD) goats reared in the derived savanna zone of eastern Nigeria and (2) 55 naturally infected slaughter goats obtained from the savanna and sahel regions of northern Nigeria. Six of the WAD goats carried natural infections of H. contortus and T. colubriformis and eight other (tracer) goats acquired their infections from a grass paddock artificially contaminated with H. placei, C. pectinata and C. punctata, during May to October. Another three WAD goats were artificially infected with mixed cultures of L3 of the latter three nematodes, while five goats were inoculated with 1500-2000 L3 of H. contortus harvested from cultures incubated at 25-30 degrees C for 8 days either in the dark or under normal laboratory conditions. Approximately 41% (9/22) of the infected WAD goats harboured arrested larvae of Haemonchus and/or Cooperia. No arrested larvae of Trichostrongylus were found in the six animals that were infected with this nematode. The level of inhibition varied from 0.4 to 20% and only three animals showed greater than 10% inhibition. This very low level of inhibition occurred in naturally and experimentally acquired infections, irrespective of the time of year. In the case of Haemonchus, the species and strain of the parasite and infection with L3 cultured in the dark also appeared not to influence the level of inhibition. By contrast, 65.5% (36/55) and 5.5% (3/55) of the northern savanna and sahel goats harboured arrested larvae of H. contortus and T. colubriformis, respectively. The mean percentage inhibition of the former was low (2-25%) during most of the rainy season (June-August) and high (75-90%) during the late rains and the dry season (October-April). The lowest and highest mean percentage inhibitions occurred during July and November, respectively.  相似文献   
3.
ABSTRACT

This paper attempts, in an exploratory manner, to identify the various ways in which unsustainable beekeeping and honey hunting practices result in the loss of important multi-purpose agroforestry tree species in bee endemic parts of Southeastern Nigeria. Both qualitative and quantitative approaches (Rapid Rural Appraisal (RRA), community fora, focus group discussions, key informant interviews, and semi-structured interview schedules) were used in an interactive manner to collect data for this study from five randomly selected communities in Nsukka, Igbo-Etiti, Uzo-Uwani, Igbo-Eze South and Udenu Local Government Areas of Enugu State. Results show that beekeeping/honey hunting in the area is traditionally gender-specific occupations involving only male members of the households, while female members play an active role in processing, preserving, and marketing the products. The majority (69.6%) of the beekeepers/ honey hunters were within the age range of 31–50, and most (75.2%) of them did not receive secondary school education. Findings reveal that outright felling of some trees in order to extract honey, cutting tree trunks open and/or cutting down tree branches and setting surrounding bush on fire are among the major factors negatively impacting on the agroforestry of the area. Species of trees particularly at risk include Irvingia gabonensis, young Chlorophera excelsa, Raphia spp., Elaeis guineensis, Brachystegia eurycome, Dialium guineense, Erythrophleum guineese and Strychnos spinosa. Recommendations are proffered to improve harvesting practices for hive and other non-timber forest products in order to avert the erosion of natural resource base of the fragile farming ecosystem of the area.  相似文献   
4.
Twenty-four Large White × Landrace crossbreed primigravid pigs, aged 7.50 to 8.00 months weighing between 86.15 and 88.24 kg were used to study the effects of feeding graded levels of soya bean meal (SBM) replaced blood meal (BM) diets on serum biochemical profile in gestating pigs. The pigs were randomly allotted to four finisher diets formulated such that BM replaced SBM at 0.0, 50.0, 75.0 and 100.0 %, respectively. The diets were T1 (100.0 % SBM, 0.0 % BM), T2 (50.0 % SBM, 50.0 % BM), T3 (25.0 % SBM, 75.0 % BM) and T4 (0.0 % SBM, 100.0 % BM). Individual animal’s daily ration of the test diets was 2.20, 2.00 and 2.50 kg at stages one, two and three of gestation. Blood sampling and analysis for the effects of the test diets on biochemical profile of the experimental animals were carried out prior to conception, at weeks 3, 7 and 11 of gestation, respectively. The result showed no significant (P?≥?0.05) dietary treatment effects on total protein, albumin, globulin fraction, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, creatinine and urea profile of the pigs fed with BM diets when compared to the control fed with 100.0 % SBM. There was however a significant (P?≤?0.05) variation in these biochemical indices in all the experimental groups at different stages of gestation. It was concluded that BM can replace 100.0 % of SBM in the diets of pregnant pigs in the tropical humid environment without any deleterious effect on their health.  相似文献   
5.
The chemotherapeutic efficacy of diminazene aceturate (Berenil)--a standard veterinary trypanocide and pentamidine isethionate (PMI)--a human trypanocide was compared in dogs experimentally infected with Trypanosoma brucei brucei. Also, the activities of the drugs on some serum liver enzymes were evaluated before and after treatment to ascertain the relative safety of the drugs. Fifteen local dogs (mongrels) were used for the study. Three of the dogs were uninfected controls, and twelve were infected with a stock of T. brucei brucei. Three of the infected dogs were untreated controls, three were given diminazene aceturate (DA) at 7 mg/kg body weight intramuscularly (i/m), another three received pentamidine isethionate (PMI) at 4 mg/kg i/m on days 14, 17, 19, 27, 29, and 31 post infection (PI) and the remaining three dogs were also given same dose of PMI on days 14, 16, 18, 20, 22, 24 and 26 PI. Both trypanocides effectively cleared the parasites from the blood of the infected treated dogs. However, the infection subsequently relapsed at day 42 PI in one of the dogs in the DA treated group which later died at day 70 PI. Relapse infection was not recorded with the PMI treated groups although two dogs died in the PMI treated group II (treatment at days 14, 17, 19, 27, 29, and 31 PI) without showing relapsed parasitaemia. The packed cell volume (PCV), red blood cell (RBC) count, and haemoglobin (Hb) level which decreased significantly following infection, were reversed by the trypanocidal treatment. The reversal in the red cell values was faster in the PMI treated groups than in the DA treated group. The serum alkaline phosphate (SAP), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) levels increased following infection and drug administration. The increase in the enzyme levels was greater in the DA treated groups than PMI treated groups. It was thus concluded that PMI given at 4 mg/kg i/m at days 14, 16, 18, 20, 22, 24, and 26 PI constituted a safe and efficient trypanocide and exhibited a superior trypanocidal action than DA in T. brucei brucei infected dogs.  相似文献   
6.
The sugar composition of the unfermented sap from oil palm (Elaeis guinensis) trees growing in the plantations of the Nigerian Institute for Oil Palm Research, Benin City, has been determined. While sucrose concentration ranges from 9.59 to 10.59% (w/v) in the pure unfermented sap, that of either glucose or fructose is much less than 1% (w/v) (0.13–0.73% w/v). Raffinose occurs in traces only (0.13–0.35 w/v). These results were derived from our improved methods which eliminate completely, or reduce to a bare minimum, fermentation of the sap during collection. The variation with time of storage of the individual sugars in the sap during fermentation to form palm wine reveals that, as sucrose steadily decreases, fructose reaches a peak at 1.51% (w/v) at the 9th hour, and thereafter declines, while glucose and raffinose remain continuously low; all sugars disappear beyond the 33rd hour. Concomittantly, pH decreases from pH 6.60 at zero time and stabilizes at pH 3.30 after 48 h, while titrable acidity increases continuously up until the 96th hour. These changes account for the variations in the quality of palm wine during storages.  相似文献   
7.
8.
Peste des petits ruminants (PPR) disease was confirmed in West African Dwarf goats. They were managed symptomatically with antibiotics and antidarrhoeics. Following clinical recovery, faeces were collected every week from 40 recovered goats to monitor excretion of the PPR virus haemagglutinins in their faeces. All the 40 recovered goats shed the PPR virus haemagglutinins for 11 weeks post recovery. Nine goats (22.5%) continued shedding the viral antigen 12 weeks post recovery. There was correlation between weekly mean haemagglutination titre of the PPR virus and time post recovery with r = -0.7504 (p < 0.01).  相似文献   
9.
To determine if egg drop syndrome 76 virus infection is among the causes of lowered egg productivity in commercial poultry farms in South Eastern Part of Nigeria and to know the prevalence of the infection, ten farms with history of lowered egg production in Nsukka local government area of Enugu State were randomly selected. Sera from ten hens in each of the selected farms were assayed for antibodies against EDS 76 virus by the haemagglutination-inhibition (HI) test. The mean HI titre of the ten hens in each of the farms was recorded as EDS - 76 antibody titre for the farm. Nine out of the 10 farms tested were positive for EDS - 76 antibodies with HI titres ranging between 16 and 256. Out of 10 flocks with production of 65% and above 9 were EDS-76 HI negative.  相似文献   
10.
The influence of seasonal changes on epidemiological and entomological indices of malaria transmission in North Central Nigeria was elucidated in a series of studies carried out between January 2004 and December 2009. The climate in the study area was divided into three seasonal periods namely, rainy (May-October), dry (December-March) and transitional (April and November), during which larval and adult anopheline mosquito collections were carried out and assessed for densities, sporozoite infection and parity rates and potentials for malaria transmission. The results indicated that the climate in the study area was clearly seasonal, with close similarities in the patterns of distribution of the climatic factors in the study sites. Mosquito densities, both at the adult and larval stages (i.e., 29.35 +/- 5.10 adult mosquitoes/man/night and 10.36 +/- 3.34 larvae/dip, respectively), were significantly (p<0.05) highest during the rainy season. However, while the former varied significantly in the three seasonal periods, the latter was not significantly different during the dry and transitional seasons. Malaria transmission risks, in terms of sporozoite rates and entomological inoculation rates, was significantly (p<0.05) least in the dry season (i.e., 2.89 +/- 1.25% and 0.37 +/- 0.21 infective bite/man/night, respectively) but the two variables were not significantly (p>0.05) different during the transitional and rainy seasons. Adult mosquito daily survival rate and adult longevity were least in the dry season (26.52 +/- 11.80% and 6.80 days, respectively) and significantly (p<0.05) highest during the rainy season (72.28 +/- 4.00% and 16.95 +/- 4.20 days, respectively). Parous rates of the mosquitoes and duration of sporogony had distinct distribution pattern from the other variables investigated. While, significantly highest parous rates were recorded in the transitional season (86.00 +/- 4.30%), duration of sporogony was not significantly (p>0.05) different during the three seasons. The epidemiology of urban malaria in North Central Nigeria was discussed from the view points of the these results and concluded that the findings should promote the development of informed temporally-targeted vector control programs for the area.  相似文献   
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