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61.
62.
Ernest J. Willoughby 《African Zoology》2013,48(1):133-176
1. The biology of six species of larks in the Namib Desert near Walvis Bay, South West Africa, was studied in 1964, 1965 and 1966.2. All species reproduced following rainfall in summer and autumn months, with the appearance of green grass and abundant insects on which the birds fed.3. The primarily insectivorous species, Certhilauda albofasciata, shows no seasonality in moulting and testicular development, and reproduces whenever local rainfall results in favourable feeding and nesting circumstances, while the primarily granivorous Spizoeorys starki and Eremopterix verticalis have markedly seasonal testicular and moulting cycles timed so that reproduction occurs only during the late summer and autumn months. Ammomanes grayi is intermediate in food habits and in timing of moulting and reproduction, and C. albescens and Mirafra naevia may also be intermediate in this respect.4. S. starki and E. verticalis are the only larks that normally drink, but flocks of both species were observed that were independent of drinking water.5. Larks avoid heat stress during daytime by keeping to the shade of stones, tufts of vegetation and mouths of rodent burrows; and nests are nearly always placed on the shady side of a stone' or tuft of grass.6. It is suggested that larks may be successful desert occupants because they have not become highly specialized and therefore can tolerate rapidly and severely changing environ-mental conditions associated with drought and irregular rainfall. 相似文献
63.
Ernest Paulini 《国际虫害防治杂志》2013,59(3):265-274
Abstract Schistosoma mansoni was first recorded in Brazil in 1908, currently official estimates are that schistosomiasis is endemic in 1,000 municipalities and possibly ten million individuals are infected. Infection foci are rural communities and irrigated areas without sewage disposal facilities. In the past The Servicio Especial de Saúde Publica: The Servico Nacional de Malaria and later the Department of Rural Endemic Diseases (DNERu) attempted with some success to control the intermediate hosts, Biomphalarla spp., and improve sanitation and water supplies. Following examination of past policies DNERu in 1965 authorised the organisation of pilot projects for the control of schistosomiasis in 4 states: Pernambuco, Bahia, Minas Gerais, and Gaunabara. In 1970 the results of the pilot projects were evaluated and recommendations made regarding drug treatment and snail control for immediate use by the Superintendencia de Campanhas of the Federal Ministry of Health, involving the use of the drug Hycanthone, the molluscicide niclosamide (Bayluscide) and complimentary measures such as drainage and education in basic sanitation. In the future with the greater urbanisation of Brazil and increasing number of irrigation projects the incidence of the disease could increase. Improvements in sanitation, education and nutritional state will counteract this. 相似文献
64.
D Grace M Dipeolu J Olawoye E Ojo S Odebode M Agbaje G Akindana T Randolph 《Tropical animal health and production》2012,44(Z1):61-66
We evaluated a group-based, participatory training intervention to improve food safety among meat processors and retailers in Bodija Market, Ibadan, Nigeria. An interactive training workshop was held for Butchers Associations' representatives who were selected to pass on information and training to their group. Meat hygiene knowledge, attitude and practice was assessed before attending the workshop and afterwards (n?=?63). It was also assessed for those who did not attend the workshop (n?=?68) but were intended recipients of training through their association. Microbiological quality of meat was assessed before and after the workshop (n?=?400 samples). After the workshop, participants significantly improved knowledge, attitude and practice in key food safety aspects; specifically, understanding sources of contamination and food-borne diseases, use of bleach and disinfectant and hand washing. Participants also shared information with an average of 18 other group members and improvements were seen in group members who did not attend the workshop but received training through their Butchers Association. Microbiological quality of meat sold also significantly improved after the intervention. In conclusion, participatory, group-based methods targeted at meat processors and retailers can improve meat hygiene knowledge, attitude and practice as well as the microbiological quality and hence safety of meat. 相似文献
65.
Ninety-three (93) horses were investigated for serum antibodies to Theileria equi (T. equi) and Babesia caballi (B. caballi) using the immunofluorescent antibody test (IFAT). Seventy-seven (82.8%) horses were seropositive; 31 (33.3%) were positive to T. equi compared to 64 (68.8%) to B. caballi while 18 (19.4%) horses were seropositive to both parasites. No significant differences in antibody frequencies among females and males for either T. equi or B. caballi were noted. Differences in seropositivity to B. caballi among age groups were not significant. Antibodies to T. equi were more frequent than to B.caballi in the age group 5 years and over than in the 1-2 and 2-4 years age groups (p<0.05). Unlike T. equi antibodies, B. caballi antibodies in horses in the county of Caroni were significantly less frequent when compared to other counties (p<0.05). Of 18 (19.4%) clinically ill horses, seven (42.9%) had clinicopathological evidence of anemia. Only one-third (6 of 18) horses were positive for the parasite on Wright-Giemsa stained blood smears and anemia was present in only 2. We report here that B. caballi and not T. equi may be the more common agent of piroplasmosis in Trinidad. 相似文献
66.
Shear press determinations of the raw product as a possible tool for quality measurement of potatoes
Texture determinations were made with a Food Technology Corporation shear press on Russet Burbank and Norgold tubers as they grew and developed from July 1 until October 15, 1970. Shear force reading increased as Russet Burbank tubers grew and increased in dry matter content. However, no increase in shear force was obtained with growth and development of the Norgold variety. Tubers harvested in the Fall were placed in 48 F storage and separated into specific gravity groups in increments of 0.005 with a brine solution. As specific gravity of the Russet Burbank variety increased, shear force readings also increased. Shear force of the Norgold Russet did not change with specific gravity changes. A very high correlation was obtained between raw shear force readings of specific gravity groups (Russet Burbank) and processed frozen french, fries of the same lots which were finish fried and shear force readings made within 3 minutes after removal from the fryer. Again, the correlation between raw shear force readings and finish fry readings of Norgold Russet was very poor, although the finish fry product readings increased as specific gravity increased. 相似文献
67.
68.
Ocular anatomy of the black pacu (Colossoma macropomum): gross,histologic, and diagnostic imaging 下载免费PDF全文
69.
Lucas L. A. Asaava Willie A. Githui Moses Mwangi Edwin Mwangi Ernest Juma Ruth Moraa Adan Halakhe Michael M. Gicheru 《Zoonoses and public health》2020,67(6):713-731
Non‐tuberculous mycobacteria are of public health significance, and zoonotic infection is attributed to the sociocultural practice of consumption of raw milk and the close human–livestock contact in pastoral communities. This study aimed at isolation, identification of mycobacteria from human sputum and camel milk and risk factors assessment in Samburu East, Kenya. Six hundred and twelve camels and 48 people presumed to have tuberculosis (TB) from 86 households in Wamba and Waso regions were screened. Camels were categorized into Somali, Turkana and Rendile breeds. Single intradermal comparative tuberculin test (SICTT) was used as a herd‐screening test on lactating camels and a milk sample collected from reactive camels. Sputum samples were collected from eligible members of participating households. A standard questionnaire on possible risk factors for both humans and camels was administered to respective household heads or their representatives. Total camel skin test reactors were 238/612 (38.9%). Milk and sputum samples were analysed at KEMRI/TB research laboratory for microscopy, GeneXpert®, culture and identification. Isolates were identified using 16S rRNA gene sequencing at Inqaba biotec in South Africa. Sixty‐four isolates were acid‐fast bacilli (AFB) positive of which M. fortuitum (3), M. szulgai (20), M. monacense (5), M. lehmanni (4), M. litorale (4), M. elephantis (3), M. duvalii (3), M. brasiliensis (1), M. arcueilense (1) and M. lentiflavum (1) were from milk; M. fortuitum (1), M. szulgai (2) and M. litorale (1) were from humans. Risk factors included the following: Turkana breed (OR = 3.4; 95% CI: 1.2–9.3), replacements from outside the County (OR = 2.1; 95% CI: 0.3–12.3), presence of other domestic species (small stock; OR = 4.6) and replacement from within the herd (OR = 3.2; 95% CI: 0.7–14.7). Zoonotic risk practices included raw milk consumption, shared housing and handling camels. Monitoring of zoonotic NTM through surveillance and notification systems is required. 相似文献
70.
A. Ian T. Walker Vernon K. H. Brown Jiro K. Kodama Ernest Thorpe Andrew B. Wilson 《Pest management science》1974,5(2):153-159
Acute and long-term mammalian toxicity studies were carried out with the 1,3,5-triazine herbicide cyanazine (I) and its two major plant and soil metabolites DW 43 85 (II) and DW 4394 (III). Depending upon the species used, the acute oral LD50 values for cyanazine ranged from 140-750 mg/kg, the values in any one species not being influenced by formulation. The acute, percutaneous LD50 values were greater than 1000 mg/kg, the maximum dose which could be administered. Cyanazine was non-irritant to eyes and skin and a non-sensitiser to skin. The acute oral LD50 in rats for (II) was 789 mg/kg and for (III) was >2000 mg/kg. In 13-week studies on cyanazine, reduced growth rates and organ weight changes were the most sensitive criteria of exposure, 25 parts/million in the diet of rats and 5 mg/kg orally dosed to dogs being considered to be without toxicological effect. In two year studies 12 parts/million in the diet of rats and 1.25 mg/kg, orally dosed to dogs produced no changes of toxicological significance. In 13-week studies with (II) and (III), intakes of up to 10 000 parts/million in the diet failed to produce any toxicologically significant changes. 相似文献