Culicoides associated with Dairy Cows at Sebele,Gaborone, Botswana

Tropical Animal Health and Production -     

Thysanoptera infestation on skin and periorbital cellulitis in ostriches (Struthio camelus) aged 14 months

AIM: To report the infestation of Thysanoptera (Limothrips denticornis) on ostriches (Struthio camelus) and to determine their relative density.

METHODS: A farm in Poland was studied on which ostriches aged 14 months were severely infested with L. denticornis (thrips). Thrips were collected and their density on the neck, torso and legs (10 cm²) of 85 ostriches determined at 0600, 1200 and 1800 h, respectively, over 7 days. At the same times, apparent densities of thrips/m² were determined in adjacent grassy areas (120 m²) on a muslin cloth impregnated with permethrin. Thrips were mounted onto slides in Hoyer's medium, for identification.

RESULTS: The apparent density of thrips was greatest at 1200 h, and was greater on the neck than the torso and legs (p=0.03). In adjacent surroundings, densities were also highest at 1200 h (mean 199 (SE 9.3) thrips/m²) and were similar to the maximum densities recorded on the necks of ostriches at that time (mean 205 (SE 6.4) thrips/m²). Ostriches engaged in excessive preening and attempted to scratch their head/neck with their feet. Numerous small, pale red papules were observed on the skin. Observations of periorbital cellulitis, conjunctivitis, blepharitis, watery discharge, inflammation, and sclerotic discolouration were noted in 65 ostriches.

CONCLUSION: Observations were commensurate with L. denticornis infestation.

CLINICAL RELEVANCE: Infestation may exacerbate stress levels and subsequently lead to a reduction in feed intake and performance. The infestation and subsequent irritation from thrips impacts negatively on the general health of ostriches by damaging skin and irritating eyes.     

Parasites of domestic pigeons (Columba livia domestica) in Sebele, Gaborone, Botswana

The following parasites were found in apparently healthy pigeons kept in Sebele: a haemoprotozoan, Haemoproteus columbae (80%); endoparasite metazoan nematodes, Ascaridia columbae (30%) and Dispharynx spiralis (10%); a cestode, Raillietina sp. (80%) and coccidian oocysts (40%); 2 ectoparasites, namely the pigeon fly, Pseudolynchia canariensis (50%) and the louse, Columbicola columbae (30%). The pigeons also had highantibody titres, (1:256) to the protozoan parasite Toxoplasma gondii (100%). The latter infection in these domestic pigeons has public health implications.     

Antibodies to Newcastle disease virus in the sera of indigenous chickens in Oodi, Kgatleng, Botswana

A serological survey was conducted to determine the prevalence of antibodies to Newcastle disease virus in apparently healthy and unvaccinated adult indigenous chickens. Haemagglutination inhibiting antibodies to Newcastle disease virus were found in the sera of 51 out of 89 (57.3%) chickens sampled.     

水稻纹枯病生防菌株的筛选、鉴定及其防治效果

为获得对水稻纹枯病有生防潜力的菌株,从湖北省恩施土家族苗族自治州植物根际土壤中分离获得菌株,筛选对水稻纹枯病菌有拮抗作用的菌株,并测定其发酵液的抑菌活性、抑菌谱及生物学特性;基于形态学特征、生理生化特征及分子生物学特征对其进行分类鉴定,并通过离体叶片、室内盆栽和田间试验进一步评价其生防潜力。结果显示,从根际土壤中共分离获得162株菌株,其中生防菌株E12对水稻纹枯病菌的抑制率最高,达94.93%,且该菌株对常见的12种植物病原菌均有抑制作用,抑制率在59.84%~93.14%之间;生防菌株E12能分泌蛋白酶、嗜铁素和淀粉酶,具有固氮及形成生物被膜的能力;结合形态学特征、生理生化特征及分子生物学特征,将菌株E12鉴定为越南伯克霍尔德氏菌Burkholderia vietnamiensis;生防菌株E12处理离体水稻叶片后,其相对病斑长度较对照显著减小,对水稻纹枯病的室内盆栽和田间防治效果分别为62.51%和67.78%。表明越南伯克霍尔德氏菌E12在防控水稻纹枯病方面有较好的潜力。     

Improving the Reproductive Efficiency by Zoo-Technical Methods at a Dairy Farm

This trial was conducted on a Hungarian dairy farm between July 2001 and December 2004. The objective of this work was to improve the reproductive efficiency with relatively high milk production. At the beginning of this trial blood and fodder samples were taken for checking the metabolic status of the animals in order to determine their health condition. The nutritive value of the daily ration for all groups met with the requirements of the Hungarian National Standard and almost all serum metabolic parameters differed between the milking and pregnant animals. Early pregnancy detection (by ultrasound) and ovulation synchronizing methods were introduced to optimize reproductive performance. The oestrus cycle was also checked by ultrasound and open cows were treated by the appropriate method in order to inseminate them as soon as possible. Efficiency of artificial insemination (AI) followed by a single prostaglandin F2alpha (PGF2alpha) and Ovsynch treatment was similar (30.8% and 29%) and less effective than AI after natural heat detection (37.1%). Provsynch (Pre-synch followed by Ovsynch) was the most effective ovulation synchronization method (conception rate=42.6%; p<0.01). Although milk production increased between 2002 and 2004 by approximately 600 kg per cow, the calving period decreased by 20 days and the number of AIs per pregnancy was also improved (0.8 AI per conception). These findings are really beneficial economically because the decrease in the calving interval returns profit for the dairy farms; one open day costs euro2.5/cow. Economical analysis showed a high profit ratio from the reproductive 'investment' on this farm. Every invested euro yielded approximately euro10.