Culicoides spp. (Diptera: Ceratopogonidae) Associated with Farmed Ostriches (Struthio camelus) in Botswana

Veterinary Research Communications -     

Limb Deformities of Farmed Ostrich (Struthio camelus) Chicks in Botswana

Limb deformities were detected in 135 out of 885 ostrich chicks, giving a prevalence of 15.3%. Tibiotarsal rotation affected 73% of the chicks with limb deformities, whereas rolled toes accounted for 36%. The right leg was more often affected than the left leg. The incidence of limb deformities was highest in 2- to 3-week-old ostrich chicks. The incidence of limb deformities was highest at the beginning of the breeding season and lowest towards the end, when it was relatively warmer. The mean serum manganese and zinc levels in deformed ostrich chicks were higher than the levels reported for normal chicks.     

Growth in the ostrich (Struthio camelus var. domesticus)

The use of the ostrich as a livestock animal necessitates an understanding of its ability to utilize specific nutrient requirements if efficient growth is to be realized. Male ostriches may have to be raised separately as they grow faster; they require higher protein diets and are more efficient feed converters for longer periods than female ostriches. Male ostriches exhibit slightly faster maturation rates than female ostriches. The corresponding age at which maximum growth is attained is 181 days for male ostriches and 199 days for female ostriches. The growth curve of ostriches is sigmoid and asymptotic. Body mass reached in 1 year is approximately 104 kg. The metabolic age of ostriches at hatching is approximately 13.7 days. Feed conversion has an impact on growth. The ostrich chick (aged <2 months) has a high feed conversion to body mass ratio of 2:1, which requires very accurate and careful management of chick nutrition.     

Nutrition and feed management in the ostrich (Struthio camelus var. domesticus)

The ostrich is an important animal in many livestock industries and in the developing world ostrich production is a valuable source of foreign currency netted from the export of meat and skins. Its successful growth and reproductive performance is dependent upon good nutrition. In Zimbabwe, one of the greatest costs involved in the upkeep of ostrich breeder birds is purchased feed (US$4555.45/10 birds p.a.). In order to cover these costs, the producer needs to ensure an adequate throughput of birds for slaughter. The energy provided by a particular feed source is important for growth and development of the bird. More research is required in ostrich nutrition.     

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.     

Bacterial, fungal and parasitic infections in the ostrich (Struthio camelus var. domesticus)

The ostrich is susceptible to microorganisms of bacterial, fungal and parasitic origin. Anthrax, caused by Bacillus anthracis, is dangerous to other livestock and humans. Salmonella is transmitted from rodents or wild bird reservoirs. Pausterellosis caused by Pasteurella multocida results in air sac infections in ostriches. Colibacillosis is caused by Escherichia coli. Tuberculosis caused by Mycobacterium avium, is very rare in ostriches. Aspergillosis principally afflicts chicks. Zygomycosis, a secondary fungal infection of the upper gastrointestinal tract, is caused by Basidia, Mucor and Rhizopus. Leucocytozoon struthionis and Plasmodium spp. are harmless protozoa transmitted from flying arthropods. The tapeworm, Houttuynia struthionis, is dangerous in young ostriches. The adult ratite fluke (Philophthalmus gralli) is transmitted to ostriches following ingestion of infected freshwater crustaceans. Tick infestations of ostrich skin in Africa include Amblyomma spp., Haemaphysalis punctata, Hyalomma spp., Rhipicephalus turanicus and Argus spp. The ostrich quillmite (Pterolichus bicaudatus) and louse (Struthioliperus struthionus) may lower skin and leather quality via pruritis and/or excessive preening and feather loss. Nemododa infections are rare.     

Anatomy and physiology of the gastro-intestinal tract and growth curves of the ostrich (Struthio camelus)

The ostrich is an important animal in many livestock industries and in the developing world. The digestive system of the ostrich differs considerably from that of non‐ruminant animals or poultry. The genetic potential of an ostrich can be described by its characteristic growth curve. This present paper presents an account of the rearing, anatomy of the gastro‐intestinal tract, and growth curves of this bird.     

Regional specialization of the Ganglion cell density in the retina of the Ostrich (Struthio camelus)

In this study, retinal whole-mount specimens were prepared and stained with 0.1% cresyl violet for the ganglion cell study in the Ostrich (Struthio camelus) . The total number, distribution, and size of these cells were determined in different retinal regions. The mean total number of ganglion cells (three retinas) was 1 435 052 with an average density of 652 cells/mm². The temporo – nasal area of the retina with high cell density were identified with the peak of 7525 cells/mm² in the central area. The size of most ganglion cells ranged from 113–403 µm², with smaller cells predominating along the temporo-nasal streak above the optic disc and larger cells comprising more of the peripheral regions. The average thickness of the retina was 196 µm. The central area was the thickest area (268.6 µm), whereas the peripheral area was the thinnest area. Thus, the specialization of ganglion cell densities, their sizes and the thickness of the retina support the notion that the conduction of visual information towards the brain from all regions of the retina is not uniform, and suggests that the temporo – nasal streak is the fine quality area for vision in ostriches.     

Sex-related differences of bone properties of pelvic limb and bone metabolism indices in 14-month-old ostriches (Struthio camelus)

1. Sex-related differences of long pelvic limb bones and serum bone metabolism indices were evaluated in 14-month-old female (N = 7) and male (N = 7) ostriches of similar body weights.

2. Densitometric parameters of femur, tibia and tarsometatarsus were determined using quantitative computed tomography (volumetric bone mineral density, calcium hydroxyapatite density and mean volumetric bone mineral density) and dual energy X-ray absorptiometry (bone mineral density and bone mineral content) methods. Geometrical parameters such as cortical bone area, cross-sectional area, second moment of inertia, mean relative wall thickness and cortical index were determined in the midshaft of bones. Mechanical properties of bones (maximum elastic strength and ultimate strength) were evaluated using three-point bending test. Serum concentrations of free amino acids, osteocalcin, N-terminal propeptide of type I procollagen, C-terminal telopeptides of type II collagen and total antioxidative capacity were also determined.

3. Bone weight and relative bone weight of all bones were significantly higher in males than in females. Significantly lower values of trabecular bone mineral density and calcium hydroxyapatite density were found in the trabecular bone of tibia in males. The highest number of the sex-related differences was observed in the tarsometatarsus where bone length, bone mineral content, cortical bone area, cross-sectional area and ultimate strength were higher in males. Serum concentrations of taurine, hydroxyproline, valine and isoleucine were significantly higher in males.

4. Higher loading of the tarsometatarsus in comparison to femur and tibia may be an important factor interacting with sex hormones in regulation of bone formation and mineralisation processes. Sex-related differences of bone properties were associated with increased serum concentration of selected amino acids in males.     

A note on endoparasites of wild ostriches (Struthio camelus) in the Mokolodi Nature Reserve,Gaborone, Botswana

A study was undertaken to investigate the prevalence of endoparasites of wild ostriches at Mokolodi Nature Reserve, Gaborone, over a 7-month period. Large numbers of strongyle eggs were recovered from faecal material in April and September and a decline in the strongyle egg counts was evident during June and July. Noteworthy was the absence of helminth eggs in faecal samples collected from chicks and coccidia oocysts from any of the ostriches.     

培养基质中添加酯化葡甘露聚糖和DON对小鼠脾细胞生长和转化的影响

将体外培养的脾细胞分为5组,以RPMI-1640为基础培养基,第1组为空白对照组;第2组为阳性对照组,添加500 μg/L DON;第3组、第4组和第5组在添加500 μg/L DON的基础上分别添加0.05%、0.10%和0.15%的EGM。在培养72 h后,测定各组培养基质中MDA含量、SOD活性、脾细胞存活率和淋巴细胞转化率。结果表明,第1组、第4组和第5组的脾细胞存活率、SOD活性极显著高于第2组(P<0.01);第1组、第4组和第5组的淋巴细胞转化率显著高于第2组(P>0.05);第2组培养液中MDA含量显著高于第1组、第4组和第5组(P<0.05);第1组、第4组和第5组各项指标差异不显著(P>0.05)。由此表明,EGM能很好地吸附DON,减轻DON对小鼠脾细胞的毒性作用;EGM在饲料中的适宜添加剂量为0.10%。     

A preliminary study on the glycosylation of the reproductive tract in the Ostrich (Struthio camelus camelus)

Glycosylation of the reproductive tract of an adult female red-necked ostrich (Struthio camelus camelus) carrying a fully formed calcified egg in her uterus when accidently killed by a blow to the head was examined using lectin histochemistry on samples from the infundibulum, magnum, uterus and vagina. Glycans in the luminal epithelium and underlying glands were described after staining with 23 lectins after neuraminidase pre-treatment in some cases. Ciliated and non-ciliated cells were evident at all levels in the luminal epithelium, the latter full of richly glycosylated secretory granules. The ciliated cells also showed glycosylation and, in the magnum, these cells often stained more intensely than the non-ciliated cells. High mannose and complex N-glycans, α1,6-linked fucosyl and sialic acid residues were present throughout the tract and there was a complete absence of GalNAcα1,3(LFucα1,2)Galß1,3/4GlcNAcß1- and rare terminal GalNAcα1- residues. Fucose in α1,2-linkage as H2 antigen and Le^y was also rare in the luminal epithelium and completely absent in glands. Terminal galactose was present in the luminal epithelium apart from in the infundibulum. Gland epithelium showed similar glycosylation to the luminal epithelium except in the magnum where there were significant differences and here the glands were packed full of large secretory granules, unlike the glands in the rest of the tract. Each section of the tract had its own specific pattern of glycosylation which could be related to the stage of egg formation.     

Effect of diet on the metabolic profile of ostriches (Struthio camelus var. domesticus)

In order to study the metabolic profile of ostriches in relation to diet, 40 animals of both sexes were divided equally into two groups and fed two diets ad libitum consisting, on a dry matter basis, of the same commercial concentrate (60%) for the two groups and of corn silage (group A) or alfalfa hay (group B). In the morning, after about 12 h of fasting, blood was collected from the wing vein. The following haematological parameters were determined with an automatic system (Ektachem 250 analyser, Kodak): glucose, cholesterol, triglycerides, lactate (LAC), total protein (TP), uric acid, total bilirubin (Tbil), creatinine (CREA), calcium (Ca), magnesium (Mg), phosphorus (P), sodium (Na), potassium (K), chloride (Cl⁻), iron (Fe), aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (AP), cholinesterase (ChE), α-amylase (Amyl), lipase (LIP) and γ-glutamyltrasferase (GGT). Diet significantly affected some parameters of the metabolic profile. Indeed, owing to the presence of alfalfa hay in the diet, group B showed, in comparison to group A, significantly higher values of uric acid (222.5 vs 387.5 mmol/L, p < 0.01), GGT (8.50 vs 11.3 U/L, p < 0.05), Tbil (8.50 vs 10.7 mmol/L, p < 0.05), Ca (2.41 vs 2.83 μmol/L, p < 0.01), Mg (1.01 vs 1.18 μmol/L, p < 0.05) and K (2.71 vs 3.16 μmol/L, p < 0.01). The levels of creatinine (27.3 vs 32.6 mmol/L, p < 0.05) and AST (344.9 vs 461.4 U/l, p < 0.01) were also higher for group B.     

Detection of circovirus with a polymerase chain reaction in the ostrich (Struthio camelus) on a farm in The Netherlands

This study describes for the first time the presence of circoviruses in ostrich tissue including embryos. A polymerase chain reaction (PCR) was used for the detection of the virus in liver samples. The use of a polymerase for low copy detection significantly increased the sensitivity of the test as well as a Southern blot. Viral DNA could be detected in chicks and eggs that did not hatch. For localisation of the virus in the liver in situ hybridisation was performed on a selection of positive liver tissues.     

阻断淋巴细胞糖皮质激素受体对鸡免疫功能的影响

为进一步证明糖皮质激素受体（ＧＲ）在介导淋巴细胞免疫功能中的作用,观察ＧＲ阻断鸡对马立克氏病病毒（ＭＤＶ）的感受性,用ＲＵ４８６阻断鸡淋巴细胞ＧＲ,当ＧＲ被阻断６０％以上时（ＲＵ４８６剂量为５０ｍｇ／ｋｇ）,鸡脾细胞诱生ＩＬ－２和ＩＦＮ活性及Ｔ、Ｂ细胞丝裂原刺激增殖活性均明显降低;外周血淋巴细胞、单核细胞、ＡＮＡＥ＋细胞减少;脾脏、法氏囊、胸腺重量与体重之比的相对重量减轻,淋巴细胞系统免疫功能呈低下状态。此时雏鸡对ＭＤＶ的易感性增高。当ＧＲ被阻断不足３５％时（ＲＵ４８６剂量为２５ｍｇ／ｋｇ）,对淋巴细胞系统免疫功能无影响。     

Localization of thrombospondin‐1 and its receptor CD36 in the ovary of the ostrich (Struthio camelus)

Angiogenesis, the formation of new blood vessels from pre‐existing vasculature, plays a decisive role for the rapid growth of avian follicles. Compared to mammals, few data on the angiogenesis in the avian ovary are available. However, whereas several pro‐angiogenic factors in the avian ovary have been recently studied in detail, little information is available on the localization of anti‐angiogenic factors. The aim of this study was to determine the localization and possible function of the anti‐angiogenic factor thrombospondin‐1 (TSP‐1) and its receptor CD36 in the ovary of the ostrich using immunohistochemistry and to correlate the results with ultrastructural data. Whereas the oocytes and granulosa cells of all follicular stages were negative for TSP‐1, myofibroblasts of the theca externa and smooth muscle cells of blood vessels showed distinct reactions. A distinctly different staining pattern was observed for CD36. The oocytes were CD36 negative. No immunostaining for CD36 could be observed neither in the granulosa cells nor in the adjacent theca interna of vitellogenic follicles. In the theca externa, blood vessels protruding towards the oocyte showed CD36‐positive endothelial cells. In conclusion, a fine balance between angiogenic and anti‐angiogenic processes assures that a dense net of blood vessels develops during the rapid growth of a selected follicle. Anti‐angiogenic molecules, such as TSP‐1 and its receptor CD36 may, after the oocyte has reached its final size, inhibit further angiogenesis and limit the transport of yolk material to the mature oocyte. By this mechanism, the growth of the megalecithal oocyte during folliculogenesis may cease.     

The effect of feeding rations with different ratios of concentrate to alfalfa hay on blood hematological and biochemical parameters of farmed ostriches (Struthio camelus)

A two-month trial was conducted to investigate the effects of pelleting rations with 70:30, 65:35, and 60:40 concentrate to high-quality roughage (alfalfa hay) ratios on hematological and biochemical parameters of ostriches. A total of 18 seven-month-old male ostrich chicks, initially weighing an average of 60–70 kg, were distributed into three different outdoor paddocks at a stocking density of six birds per paddock. In the morning, blood collection was made from the wing vein after about 12 h of fasting. All rations resulted in no significant change in hematological parameters. However, with increasing alfalfa inclusion rate, the heterophil/lymphocyte ratio tended to be lower (P?=?0.089); whereas the values of hemoglobin, packed cell volume (PCV), and mean corpuscular hemoglobin (MCH) tended to be higher (P values 0.069, 0.072 and 0.094, respectively). In terms of plasma biochemical parameters, increasing the ratio of concentrate to alfalfa hay in ostrich diets resulted in significant (P?<?0.05) depression in the values of glucose (up to 20.2 %), total cholesterol (up to 19.2 %), creatine kinase (up to 27.9 %), and aspartate aminotransferase (up to 29.9 %). Additionally, the 65:35 or 60:40 rations caused a decrease in low-density lipoprotein cholesterol level (27.9 and 42 %, respectively; P?=?0.008) compared to the 70:40 ration. Without exception, no rations affected the values of leukocyte subsets, total protein, albumin, globulin, uric acid, alanine aminotransferase, gamma glutamyl transferase, triglycerides, high-density lipoprotein cholesterol, and very low density lipoprotein. Based on our results, the concentrate to alfalfa ratio of 60:40 could be suggested as optimum ratio for good health conditions of juvenile ostriches.     

维生素E缺乏对雏鸡淋巴细胞膜抗氧化及膜流动性的影响

用低维生素E（VE）和添加不饱和脂肪酸的日粮饲喂雏鸡，建立VE缺乏雏鸡模型。分离全血淋巴细胞并制备细胞膜，检测淋巴细胞膜超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活力及丙二醛(MDA)含量；采用荧光偏振法检测淋巴细胞膜流动性。结果表明，VE缺乏雏鸡淋巴细胞膜SOD和GSH-Px活力及膜流动性低于对照组，MDA含量高于对照组，组间差异显著或极显著 (P<0.05、P<0.01)。说明VE对维持雏鸡淋巴细胞膜功能起重要作用。     

Preliminary results on the use of diagnostic ultrasonography as a management tool to quantify egg production potential in breeding ostrich (Struthio camelus australis) females

An ostrich breeding flock, joined as individual breeding pairs (n = 136 pairs), was used to investigate the possibility of diagnostic ultrasonography as a method to predict the reproductive performance of ostrich females during a breeding season. Follicular activity was easily detected and quantified by using diagnostic ultrasonography. One to 8 follicles were recorded in 25% of females scanned at the beginning of the 9-month breeding season. At the end of the breeding season, 1-3 follicles were observed in 28.7% females. Females in which follicular activity was observed came into production earlier than those in which no follicles were observed, with the mean (+/- SE) number of days to the production of the 1st egg being 22.3 +/- 12.5 and 87.4 +/- 7.2 days, respectively. Females in which follicular activity was observed at the beginning of the breeding season, produced on average 181% more eggs during the 1st month of the breeding season (P < 0.01) than females in which no follicular activity was observed (6.67 +/- 0.70 vs 2.37 +/- 0.41 eggs). Egg production over the first 2 months of breeding and over the entire breeding season were similarly affected (P < 0.01), with the mean number of eggs produced over the first 2 months of the breeding season being 14.7 +/- 1.5 for females with observed follicular activity and 7.4 +/- 0.9 eggs for females with no observed follicular activity. Females in which follicular activity was observed at the end of the breeding season produced on average 108% more eggs (P < 0.01) during the last month of the breeding season than females in which no follicular activity was observed (2.77 +/- 0.43 vs. 1.33 +/- 0.27 eggs). There was a tendency (P = 0.06) for egg production over the last 2 months to be similarly affected (6.10 +/- 0.85 vs 4.19 +/- 0.54 eggs). No relationship with egg production over the entire breeding season was found for the end-of-the-breeding-season observations. Diagnostic ultrasonography can thus be used as a management tool to identify reproductively healthy ostrich females and also females with a higher egg production potential over a period of 2 months after or prior to assessment. Future studies should focus on the development of the technique to predict reproductive performance over entire breeding seasons for selection purposes.     

黄芪多糖对雏鸡外周血T淋巴细胞转化功能的影响

将１０８只１日龄伊莎系蛋用公雏均分为３组：一组为对照,其余２组在３日龄时,于背侧颈部皮下分别注射０．２、０．４ｍＬ黄芪多糖注射液（０．０１ｇ／ｍＬ）１次,再分别于７、２１、３５、４９日龄时采用ＭＴＴ比色法及微量全血培养３Ｈ－ＴｄＲ掺入法检测外周血Ｔ淋巴细胞转化率的动态变化。结果表明,黄芪多糖对２１、３５日龄雏鸡Ｔ淋巴细胞转化功能有增强作用,且与剂量有相关性,而对７、４９日龄雏鸡的作用不明显。ＭＴＴ比色法与３Ｈ－ＴｄＲ掺入法的检测结果无显著差异（Ｐ＜０．０５）。