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Artificial insemination (AI) in ostriches may present potential solutions to high proportions of infertile eggs commonly recorded on commercial farms and assist in reducing the number of males for breeding purposes thereby leading to a more economical and efficient farming system. Although non-invasive methods to collect semen and to artificially inseminate female ostriches have been developed, the insemination dose for maximum fertility of eggs remains unknown. This study was thus conducted to determine the minimum sperm dose that would promote fertility of eggs following AI in female ostriches. A total of 22 South African black ostriches (7 males and 15 females) aged between 2 and 9 years old were used. Semen samples were collected using the dummy female method and diluted 1:4 (semen: diluent) with an ostrich specific semen diluent. Females were inseminated with various sperm doses of diluted semen from the same male three times a week, every second day resulting in a total sperm dose of A: <2.5 × 109, B: 2.5–5 × 109, C: 5–7.5 × 109 and D: 7.5–9.6 × 109 sperm/week. Eggs produced after insemination were opened to determine the fertilization status of the germinal disc (GD) with an unaided eye. The fertile period was then calculated as the number of days fertilized eggs were laid after the last AI. Furthermore, the number of sperm trapped in the outer perivitelline membrane (sperm OPVL) above the GD region was counted under fluorescent light, following staining with 4′,6-diamidino-2-phenylindole to determine the rate of sperm loss and the number of days up to when the last egg containing sperm was laid. On average, a mean (±sd) of 35.34 ± 25.72% eggs produced after AI were fertilized. Fertility was lower (mean ± se) when sperm dose A was used (6.71 ± 9.40%), as compared to sperm dose B (46.01 ± 6.71%), C (37.34 ± 6.60%) and D (37.75 ± 8.36%) (P < 0.05). No significant difference was recorded in the latter three doses (P > 0.05). Furthermore, the length of the fertile period and the rate of sperm loss did not differ significantly between sperm doses (P > 0.05). Hence, a sperm dose of between 2.5 and 5 × 109 sperm/week is recommended to optimize fertility after AI in ostriches, as increasing the sperm dose would not benefit fertility. Further studies are, however, needed to determine the frequency of insemination that would maintain fertility throughout the breeding season as well as hatchability of eggs laid after AI. • Minimum sperm dose for optimal fertility and fertile period after artificial insemination in farmed ostriches was estimated. • A range of sperm dose inseminated per week was: <2.5 × 109, 2.5–5 x109, 5–7.5 × 109 and 7.5–9.6 × 109 sperm. • The minimum sperm dose optimizing fertility was 2.5–5 × 109 sperm per week. • No significant increase in fertility with higher sperm dose was recorded. • Length of the fertile period did not differ between sperm dose treatments. [ABSTRACT FROM AUTHOR]

Successful assisted reproduction techniques, with specific focus on in vitro semen storage for artificial insemination, are dependent on certain key elements which includes the biochemical profiling of semen. The objective of this study was to complete an ostrich seminal plasma (SP) evaluation by inductively coupled plasma mass spectrometry (ICP-MS) among seven males at different daily intervals (day 1, 3, 7, 11, 15, 19, 21, 23, 25, 26, 27, 28) for a period of 28 days during spring (August to September) for mineral profiling. The effect of collection day and male on sperm concentration, semen volume and seminal plasma volume, was explored as well as the relationships amongst these specific sperm traits and SP minerals. Variation amongst SP mineral concentrations, accounted for by the fixed effects of sperm concentration, semen volume, seminal plasma volume, collection day and male, ranged from 18% to 77%. Male had the largest effect on variation in SP minerals, namely: phosphorus (P), potassium (K), calcium (Ca), sodium (Na), boron (B), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), molybdenum (Mo), barium (Ba), arsenic (As) and selenium (Se). Sperm concentration instigated fluctuations of P, magnesium (Mg), B, zinc (Zn), Fe, aluminium (Al), Se, manganese (Mn) and lead (Pb). Semen volume had an effect on Na, K, B, Pb and Ba while seminal plasma volume only influenced variation in Na. There were fluctuations among collection days of specific micro minerals, Ni and Mo, with initial Ni concentrations being relatively greater and Mo at lesser concentrations. Semen volume, seminal plasma volume and sperm concentration varied amongst males. Sperm concentrations during the initial collection days, 1 and 3, were less than that for days 7 to 28. Significant variation of SP minerals and sperm characteristics among ejaculates and males suggest an association of these specific elements with sperm function and are, therefore, considered to be of potential importance to success of assisted reproduction technology for the ostrich. The relationship amongst sperm concentration and collection day confirms the need to conduct an initial period of collection to stabilise a greater sperm concentration to optimise sperm numbers for artificial insemination purposes. [ABSTRACT FROM AUTHOR]

The dilution of semen is a very important initial process for semen processing and evaluation, storage and preservation in vitro and efficient artificial insemination. The aim of the study was to evaluate the effect of two synthetic diluents (OS1 and OS2) on ostrich sperm motility parameters during in vitro storage. Formulation of OS1 was based on macro minerals (Na, K, P, Ca, Mg) and OS2 on the further addition of micro minerals (Se and Zn), based on mineral concentration determined in the ostrich seminal plasma (SP). Sperm motility was evaluated at different processing stages (neat, after dilution, during storage and after storage) by measuring several sperm motility variables using the Sperm Class Analyzer® (SCA). Processing (dilution, cooling and storage) of semen for in vitro storage purposes decreased the values for all sperm motility variables measured. The percentage motile (MOT) and progressive motile (PMOT) sperm decreased 20% to 30% during 24 h of storage, independent of diluent type. Quality of sperm swim (LIN, STR and WOB), however, was sustained during the longer storage periods (48 h) with the OS2 diluent modified with Se and Zn additions. Quality of sperm swim with use of OS1 was 6% to 8% less for the LIN, STR, and WOB variables. Male fitted as a fixed effect accounted for >60% of the variation for certain sperm motility variables (PMOT, MOT, VCL, VSL, VAP and ALH) evaluated at different processing stages. Semen from specific males had sustained sperm motility characteristics to a greater extent than that of other males during the 24-h storage period. [ABSTRACT FROM AUTHOR]

In this study, the lipid profile of 5 different edible tissues (leg, thigh, heart, gizzard, and liver) of ostrich was analyzed. Ostrich edible tissues presented a low fat content (<5 g/100 g wet basis). Gizzard and heart revealed the highest amounts of total cholesterol (1.77 and 1.47 mg/g wet basis, respectively), differing significantly from all other tissues (which averaged 0.95 mg/g wet basis). The main tocochromanol in all tissues was α-tocopherol (10.3 µg/g wet basis in heart and an average of 3.4 µg/g wet basis for all the remaining tissues). All the samples presented a fatty acid profile, dominated by polyunsaturated fatty acids (PUFA) (>38%), namely, linoleic and arachidonic acids. The leg presented simultaneously the highest PUFA/saturated fatty acids (SFA), the lowest n-6/n-3 ratios, and the most favorable lipid quality indices among all tissues in comparison. [ABSTRACT FROM AUTHOR]

The development of a flock of females that can produce eggs and maintain egg production rate without the presence of males is a prerogative for a viable artificial insemination protocol in ostriches. Over six consecutive breeding seasons (May–December, 2009–2014), we recorded the egg production performance of 40 single-penned (ART) South African Black ostrich females (2–9 years of age), and compared these records with the egg production of 162 pair-mated females of comparable age from the breeding flock (BP). ART females laid significantly fewer eggs than BP females (mean ± SEM: 3.49 ± 0.13 eggs per month vs. 4.64 ± 0.09 eggs per month respectively; P < 0.001). Both groups showed a similar pattern of laying, with a peak production in July to September. The mean egg weight of ART females was significantly lower than those of BP females (1367 ± 2.25 g vs. 1423 ± 1.1 g, respectively; P < 0.001). Furthermore, female age significantly affected egg production and egg weight whereby BP females reached a peak egg production at 3 years of age, while in ART females, egg production was the highest at 5 years of age. Interestingly, the number of eggs produced, clutches and eggs per clutch of ART females were independent of visual stimulation from the males. These results indicate that male presence is not needed to ensure egg production. Continuous recruitment of young females based on human-friendly behaviour to breeding by artificial insemination from high egg production performance parents could improve egg production of the ART flock. Studies are also needed to gain a better understanding of underlying physiological mechanisms promoting spontaneous ovulation in this species. [ABSTRACT FROM AUTHOR]

In most countries, ostrich farming is considered a developing branch of the efficient poultry industry. The profitability of ostrich farm requires specific consideration of productions features such as the female fertility, egg production, hatchability, and growth performance. Hence, this study aimed to fit nonlinear functions to describe the ostrich egg production pattern to achieve the most appropriate and recommendable mathematical function for future studies. For this purpose, 14,507 daily records of 184 female ostriches in 5 production seasons (periods) during 2016 to 2021 were used. Five nonlinear functions including Incomplete gamma (Wood function), Corrected gamma (McNally), nonlinear Logistic (Yang), Logistic (Nelder), and Lokhorst were fitted for modeling the egg production curve in ostrich. The goodness of fit criteria's including Mean Square Error (MSE), Likelihood Ratio Test (LRT), Akaike Information Criterion (AIC), and Bayesian Information Criterion (BIC) were used to evaluate and selection of the best function. The results indicated that the Wood and the McNally functions with a slight difference in all fitting criteria were the best-fitted functions and the Yang function with the highest values of MSE, LRT, AIC, BIC, were the most inappropriate function to describe the ostrich egg production curve. The McNally and the Wood can be recommended as appropriate functions to describe egg production during 5 production seasons in the studied ostrich flock. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii has a worldwide distribution with different genotypes reported in animals and humans. The parasite is of great importance to food production and public health, highlighted by the high diversity of hosts, i.e. ostriches. This study aimed to determine the prevalence of T. gondii infection in ostriches from a Brazilian slaughterhouse, the genotype, and the associated risk factors. T. gondii antibodies were detected in 38/344 (11.05%) serum samples using the modified agglutination test using formalin-fixed tachyzoites (MAT-HS); the parasite was isolated from 14/38 (36.84%) ostrich brain samples using the mouse bioassay; and the DNA was detected from 25/38 (65.79%), using PCR. In farms, the water tank was considered the main risk factor (OR = 141.87; p-value < 0.05), and oocysts were detected in 30% (6/20) in soil of paddocks before animals were slaughtered (1st sampling), and 40% (8/20) one-year after (2nd sampling) using microscopy and PCR. Non-ostrich fecal samples on the ground resulted negative. Bioassay isolation was confirmed by PCR. All PCR positive samples were sequenced and resulted in 100% homology to Toxoplasma gondii repetitive DNA sequence (GenBank access number EF648168-1). These samples were also typed through RFLP-PCR using 11 markers: SAG1, SAG2 (5′–3′SAG2 and alt.SAG2), SAG3, BTUB, GRA6, L358, c22-8, c29-6, PK1, Apico and CS3. Two isolates had a complete genotype, typed from the ostrich tissue. In ostrich samples, the parasite load ranged from 19,043 (TgOsBr1, avirulent) to 54,829 parasites mL −1 (TgOsBr2, virulent) using qPCR, whereas soil samples ranged from 11 to 2,275 parasites mL −1 . Both typed isolates resulted on atypical clones, one previously reported to cause congenital toxoplasmosis in Brazilian patients (TgOsBr1, ToxoDB #206). Thus, these findings support the occurrence of T. gondii in slaughtered ostriches from Brazil, ostriches as sentinel for environmental contamination with T. gondii , the genotypic variability in Brazilian isolates, and the first isolation and genotyping of T. gondii from Brazilian slaughtered ostriches. [ABSTRACT FROM AUTHOR]

The success of assisted reproduction techniques is dependent on a sound foundation of understanding sperm characteristics to evaluate so as to improve semen processing. This study offers a descriptive basis for ostrich semen quality in terms of sperm function characteristics (SFC) that include motility, measured by computer assisted sperm analysis CASA (SCA ® ), viability (SYBR14/PI) and membrane integrity (hypo-osmotic swelling test). Relationships among these SFC’s were explored and described by correlations and regressions. Certain fixed effects including the dilution of semen, season, year and male associated with semen collection were interpreted for future applications. The seasonal effect on sperm samples collected throughout the year suggested that it is prudent to restrict collections to spring and summer when SFC’s and sperm concentration are maximized, compared to winter when these aspects of sperm quality are suppressed. Dilution of ejaculates helped to maintain important SFC’s associated with fertilization success. The SFC’s and sperm concentration varied among males, with specific males, having greater values for the percentage of motile (MOT) and progressively motile (PMOT) sperm, as well as sperm velocity (VCL, VSL, VAP) and linearity (LIN) variables. Males may thus be screened on these variables for inclusion in an artificial insemination (AI) programme to optimize fertility success rates. [ABSTRACT FROM AUTHOR]

Raising ostriches became an important economic activity after their products became commodities. The health of farm animals is of paramount importance, so assessing basic immunological responses is necessary to better understand health problems. We developed a method to obtain ostrich thrombocytes and macrophages. The thrombocytes died by apoptosis after 48 h in culture, and the macrophages expanded in size and increased the number of acidic compartments. Macrophages were activated by chicken interferon-γ, producing high levels of nitric oxide. Toxoplasma gondii was able to infect these macrophages, and activation controlled parasitic reproduction. T. gondii, however, persisted in these cells, and infection reduced the production of nitric oxide. These results are important for the future assessment of the basic cellular and immunobiology of ostriches and demonstrate T. gondii suppression of nitric oxide production. [ABSTRACT FROM AUTHOR]

At present, the ostrich industry is inefficient, on account of being characterised by inadequate egg production, high embryo mortality, poor chick survival and suboptimal growth rates. However, as ostrich farming commenced only in the mid 19th century in South Africa, farmed ostriches have had a short period to adapt to the commercial production environment. Hence the poor production results observed could either reflect their failure to adapt to the farming environment, or alternatively, a failure of the ostrich industry to implement proper practices to meet the needs of this species. Limited research has been undertaken to identify and integrate behavioural requirements of ostriches in such environments, in order to reduce potential stress through improving both reproductive performance of the birds and their general welfare. In this paper, we review recent progress in our understanding of ostrich reproductive behaviour both in the wild and in farming environments, with a specific emphasis on female strategies to improve offspring fitness within the context of the ostrich polygynous mating system. In addition, we discuss production and welfare implications of the unusual ostrich communal nesting system, in a farming environment. [ABSTRACT FROM AUTHOR]

The success of artificial breeding program depends largely on the reproductive performance of males. Male performance can vary with season and age impacting on quality and quantity of semen collected for artificial insemination purposes and therefore fertility of inseminated females. We examined variation in semen output and male libido of seven male ostriches (aged 2–5 years) over a period of 24 months. We collected ejaculates using a dummy female and measured semen characteristics (ejaculate volume, sperm concentration, number of spermatozoa per ejaculate, sperm motility and morphology) and male libido (willingness to mount the dummy). A total of 1006 ejaculates were collected. Across months, the volume of semen (mean ± SEM) ranged from 1.03 ± 0.12 mL to 1.85 ± 0.07 mL, the sperm concentration from 3.21 ± 0.12 × 10 9 /mL to 4.16 ± 0.74 × 10 9 /mL, and the number of spermatozoa from 3.42 ± 0.28 × 10 9 to 7.66 ± 0.47 × 10 9 . The largest volume of ejaculates and the highest number of sperm were collected in spring. Ejaculates with higher number of normal sperm were also collected in spring–early summer, whereas ejaculates with higher numbers of live abnormal and dead sperm were collected in winter. Sperm motility was relatively constant over months, despite a reduction in summer (January–February), while male libido peaked in winter (June–July) and spring (October–November). Furthermore, we observed high individual variation between males for all variables tested, except for motility. These results indicate that collections conducted in spring yield higher number of spermatozoa, when the libido of males is also at a maximum. Therefore in this species seasonal variation in semen quality should be considered in breeding programmes by artificial insemination to maximise fertility. [ABSTRACT FROM AUTHOR]

Abstract: While ostriches are relatively wild birds with a short period of domestication, some birds demonstrate a strong interest in humans. Human imprinting of chicks could therefore facilitate the cooperation of birds for assisted reproduction technology purposes, improving the quality of human–bird interactions and consequently promoting the welfare of the birds. We investigated the effect of 4 different husbandry practices performed at an early age (standard husbandry, two extended human care treatments and foster parent care) on the response of one-year-old ostrich chicks (N =206) to human presence. Specifically, we tested whether chicks exposed to more human presence and care (Imprint 1 and 2) would be more docile towards humans, as opposed to those exposed to standard husbandry practices (Standard) or foster parenting (Foster). Behavioural observations were performed 3 times a week for a period of 3 months when the birds reached an age of approximately one year. The following behaviours towards the human observer were recorded: willingness to approach the human (approach), allowing touch by the human (touch), wing flapping, the keeping of a distance from the human (distance), sexual behaviour and aggressive behaviour. We consistently found that Imprint 1, Imprint 2 and Standard chicks were significantly more inclined to approach and create contact with the observer than Foster chicks. However, no differences in approaching, touching, keeping a distance or wing flapping was observed between Imprint 2 and Standard chicks. Furthermore, no sexual or aggressive behaviour repertoires were recorded during the observation period. These results suggest that human imprinted chicks and chicks reared under standard husbandry practices are more docile than chicks reared by foster parents. Hence, such expression of friendly behaviour and apparently reduced fear towards humans could potentially lead to tamer birds, improved welfare and subsequently more efficient production. However, the lack of differences between chicks subjected to a reduced intensity of imprinting and chicks reared under standard husbandry conditions stresses the need for further investigations in this species, and specifically in terms of sexual and/or aggressive display towards humans when the birds reach full sexual maturity. [Copyright &y& Elsevier]

Abstract: Libyostrongylus sp. are nematodes that infect ostriches. Libyostrongylus douglassii was first described in ostriches from several countries in the world. Later Libyostrongylus dentatus was morphologically identified in ostriches in the USA and Brazil, and mixed infection is common in the latter country. The internal transcribed spacer (ITS) region of the ribosomal DNA gene is used for genetic variability assessment and phylogenetic reconstruction for many organisms. Through genetic analysis the status of different species morphologically defined was confirmed and a molecular method was developed to differentiate both species. ITS1, 5.8S, ITS2 regions of L. douglassii and L. dentatus were characterized. Regarding complete ITS region, the K2-p genetic distance between the species was 0.060 (SE 0.008) and the intra-specific distance was 0.002 (SE 0.001) for L. dentatus and 0.006 (SE 0.002) for L. douglassii. NJ and MP phylogenetic analysis of ITS1 and ITS2 regions indicated that both species belong to the Trichostrongylidae family, and are evolutionarily different, suported by high bootstrap value. Based on ITS DNA polymorphisms, a molecular approach was designed to detect both species. These results are the first molecular characterization of L. douglassii and L. dentatus, and provide new tools for the identification of these parasites of veterinary importance. [Copyright &y& Elsevier]

The objective of this study was to fit growth curves using nonlinear and linear functions to describe the growth of ostriches in a Brazilian popula-tion. The data set consisted of 112 animals with BW measurements from hatching to 383 d of age. Two non-linear growth functions (Gompertz and logistic) and a third-order polynomial function were applied. The parameters for the models were estimated using the least-squares method and Gauss-Newton algorithm. The goodness-of-fit of the models was assessed using R2 and the Akaike information criterion. The R2 calculat-ed for the logistic growth model was 0.945 for hens and 0.928 for cockerels and for the Gompertz growth model, 0.938 for hens and 0.924 for cockerels. The third-order polynomial fit gave R2 of 0.938 for hens and 0.924 for cockerels. Among the Akaike information criterion cal-culations, the logistic growth model presented the low-est values in this study, both for hens and for cockerels. Nonlinear models are more appropriate for describing the sigmoid nature of ostrich growth. [ABSTRACT FROM AUTHOR]

Abstract: Ostriches were imported to Brazil in the early 1990s without appropriate parasite control leading to a co-importation of parasites. Libyostrongylus douglassii, Libyostrongylus dentatus and Codiostomum struthionis are nematodes of the ostriches that have been reported on some Brazilian farms but no national survey has been performed. Moreover, little is known about anthelmintic usage to control these parasites in Brazil. Therefore, the occurrence of L. douglassii, L. dentatus and C. struthionis and the anthelmintic management practices in Brazilian ostrich farms were studied. A questionnaire about management practices and information on how to collect, store and ship feces to the laboratory were sent to 17 farms located in 9 Brazilian states. Received fecal samples were submitted to fecal cultivation and larval harvested. Infective larvae were morphologically analyzed and quantified. The majority of the farms (88%) used an anthelmintic at least once a year. Ivermectin was the principal anthelmintic. Libyostrongylus sp. and C. struthionis were found in samples from 76 and 18% of the examined farms, respectively. The presence of L. douglassii (61–97%) was higher than L. dentatus (3–57%) and C. struthionis (2–30%). At the farm level, both species of Libyostrongylus were always found together. Sheath tail measurements of their infective larvae were crucial for morphological diagnosis. L. dentatus and L. douglassii are well adapted to Brazil and are widely distributed in the Brazilian territory, proving that this mixed infection in Brazilian ostrich''s farms is common. [Copyright &y& Elsevier]

Abstract: Newcastle disease virus (NDV) strains isolated from ostriches have been genotyped for the first time by partial sequencing of the F gene to determine the epidemiologic role that this species can play within ND outbreaks. Fifteen additional NDV strains, mostly isolated from chickens but also from pigeons and penguins, were also included in the study to determine genetic relationships with ostriches NDV isolates. High genetic diversity was demonstrated in ostrich NDV isolates, as the 10 isolates were grouped in four distinct NDV genotypes. In agreement with the results obtained when chicken isolates have been molecularly characterized, the predominant genotype in ostriches was the genotype VII. More interestingly, evidences of recombination between genotype II and VII were observed in one ostrich isolate and in two further chicken isolates. Therefore, it seems that ostriches may play a relevant role in the ecology and epidemiology of ND particularly in those regions where they have an increasing farming importance as minor poultry species. [Copyright &y& Elsevier]

Abstract: The success of an artificial insemination program in ostriches is highly dependent on the yield of viable semen. We, therefore, tested how semen output is affected by three different collection frequencies: once every 2d (48h interval), daily (24h interval), and twice a day (6h interval). Ejaculates were collected from seven male ostriches (aged 2–4 years) for 10 consecutive days using the dummy female method. We assessed semen characteristics (sperm motility, volume, concentration, number of sperm per ejaculate and sperm viability) and male libido (the delay between the presentation of the dummy and ejaculation, and the willingness to mount the dummy). The total daily output of semen and the number of sperm were greater at the 6h collection interval than at the 24h or 48h interval while sperm motility and viability were not affected. At the 6h interval, the number of live normal sperm increased over the treatment period while the number of live abnormal sperm was reduced. Furthermore, the time that males took to mount the dummy and their willingness to copulate with the dummy were unaffected by collection frequency. Across males we observed great individual variation in both semen characteristics and libido suggesting there is the potential to increase the efficiency of semen collection by selecting superior males. These results indicate not only that two collections per day yield maximum semen output and may improve semen viability, but also that quantifying variation between males may help further increase semen collection efficiency. [Copyright &y& Elsevier]

In the last decade ostrich farms spread throughout the world as an alternative source of investment. Although previous studies have reported hematology and biochemical values for ostriches from several regions of the world, little information is available regarding leukocyte morphology. This study reports the morphology and ultrastructure of ostrich leukocytes and hematology and biochemical values from birds raised in Brazil. Heterophils presented a lobulated nucleus, and fusiform, and acidophilic and peroxidase-negative granules. Ultrastructurally, 2 kinds of cytoplasmic granules were observed: one was large and fusiform and the other smaller with heterogeneous morphology and electrondensity; granules were peroxidase-negative. Eosinophils had a kidney-shaped eccentrically placed nucleus that was rarely lobulated and eosinophilic, round, and peroxidase-positive granules. At the ultrastructure level, 2 main kinds of granules with the same size and form but different electron density were seen; granules were peroxidase-positive. Lymphocytes and thrombocytes had the same characteristics of other avian species; monocytes presented morphological heterogeneity. Hematological and serum biochemical profiles had no sex influence and were established for ostriches raised in southeastern Brazil. These parameters will help the diagnosis of specific ostrich pathologies and serve as basic knowledge for studies in immunology and comparative avian pathology. [ABSTRACT FROM AUTHOR]

Ostrich females producing eggs in the absence of males was a major breakthrough for the development of an artificial insemination (AI) protocol. This study evaluated monthly egg production (EP) and average egg weight (EW) for 71 individually penned female ostriches from 2009 to 2020 and estimated the genetic parameters for these traits. EP was highly variable compared to EW (coefficients of variation: 124.9 vs. 10.27%, respectively). EP continued throughout the year with maxima from July to December and minima in February and May. The two-trait heritability (h2) for EP was low at 0.13, while EW had a higher h2 of 0.40. EP and EW were not genetically correlated. The genetic improvement of EP and EW for females used for AI is feasible. Further studies should target incubation and hatching traits after AI. [ABSTRACT FROM AUTHOR]

Abstract: Codiostomum struthionis is a nematode parasite of the ostrich caecum. Little is known about its pathology, being considered by many authors as a non-pathogenic parasite. Infections by C. struthionis are sometimes overlooked because its eggs are indistinguishable from another ostrich nematode, Libyostrongylus spp. Fecal cultures and infective larvae identification are necessary for proper identification. The aim of this study is to provide improved morphological characterization of adults and infective larvae of C. struthionis. Ten caeca of adult ostriches were collected and washed in 0.09% saline solution. Male and female nematodes were collected and quantified separately. Nematodes were fixed in A.F.A. for optical microscopy or fixed in Karnovsky solution for scanning electron microscopy. To obtain infective larvae, fecal samples were collected at sites of high concentration of parasites in the caeca and fecal cultured. The resultant larvae were identified and measured with light microscope at 400×. Nine of the 10 slaughtered ostriches were parasitized by C. struthionis. All nematodes were found in the distal third of the caeca. A total of 566 parasites were recovered (234 males and 332 females). All the cultured larvae had characteristics of C. struthionis (rounded cephalic region with a flat extremity, an acute larvae tail termination and a long and filamentous sheath tail). All the adult parasites were characterized as C. struthionis. Through the analysis of the infective larvae it was determined that the morphology of the larvae tail was the best trait to use in the distinction of this species (live bird diagnosis). [Copyright &y& Elsevier]

Abstract: The differentiation of the species of the Libyostrongylus genus is only possible with the obtainment of the adult parasites in the ostriches proventriculus and gizzard. The present work confirms that it is possible to differentiate the infective larvae of L. douglassii and L. dentatus allowing the differential diagnosis of these species by fecal culture. To show this, adult females from both species were collected from ten proventriculus from adult ostriches and separated by species. Both groups were macerated individually added to sterilized feces for standard fecal cultures. The infective larvae were recovered, identified, quantified and measured. All proventriculus analyzed were parasitized by Libyostrongylus spp. and a clear heterogeneous location for each species was observed. The infective larvae from the fecal cultures of macerated L. douglassii presented a mean total length of 874.3±33.80μm, and a short sheath tail (29.5±4.11μm) with acute termination. The infective larvae from the macerated L. dentatus presented mean total length of 856.0±43.63μm, long sheath tail (61.2±9.52μm) with filamentous termination. The mean measures of the tails of both species had a significant difference. The differentiation of the infective larvae of L. douglassii and L. dentatus by fecal cultures will facilitate the diagnosis of both species for further understanding the Libyostrongylus biology. [Copyright &y& Elsevier]

Abstract: The genus Libyostrongylus includes three species, L. douglassii, L. dentatus and L. magnus that occur as parasites in the proventriculus of Struthio camelus. We confirmed a mixed infection by L. douglassii and L. dentatus in farmed ostriches from the southeast of Brazil for the first time, and provided new information on some morphological characters that differentiate these species. Adult nematodes collected from the proventriculus of ostriches were observed by light and scanning electron microscopy. Morphologic characterization and morphometric analysis of the nematodes enabled the distinction of both species and corroborated results of prior studies. Specimens of L. dentatus have a buccal capsule with a prominent esophageal tooth. Furthermore, males and females of L. dentatus were larger (4954 and 9347μm) than those of L. douglassii (3411 and 4229μm), but measurements for most characters in both species were smaller then those previously reported. Besides, the cephalic structure based on scanning electron microscopy differs, and L. dentatus has thick lips with round papillae, whereas L. douglassii has fine lips with lengthened papillae. The confirmation of both species in South America strongly suggests that the mixed infection may be common in farmed ostriches. [Copyright &y& Elsevier]

Abstract: Although the ostrich has been bred for several decades for feathers and/or meat, its behaviour has received limited attention. To our knowledge there are just descriptions of behavioural repertoire or detailed measurements of behaviour, but in limited contexts. We recorded the behaviour of six 4-year old Black neck ostrich (Struthio camelus domesticus) pairs, kept in and already acquainted to 900m2 paddocks. This longitudinal study spanned one solar year and the birds were observed individually during six 120-min observational sessions per month, although the statistical basis used was at season level. We focussed on the behaviour transitions, more than recording the behaviour duration only, as transition recording allows elucidation of the behaviour repertoire. The 22 behaviours considered were recorded continuously with a digital event recorder. Most transitions were one-way transitions in both sexes and had small variation among seasons. This suggests low variability in behaviour performance, although the existence of stereotypes is unlikely. Males displayed a slight, but constantly higher, number of transitions than females, showing that they possess a wider, or more varied, behavioural repertoire. There were many transition loops, not random and indicative of some rigidity in sequence repetition. In both males and females the total amount of transitions relied on a very few activities, indicative of a few widely used behaviours, particularly those connected to locomotion, which repeatedly followed or preceded many others. Walking was an activity greatly involved in transitions in both winter and spring, following and preceding many other behaviours, showing that even in captivity, locomotion maintains its importance for reproduction. [Copyright &y& Elsevier]

Abstract: Domestic production of ostrich in Brazil started in the beginning of the last decade, but its sanitary state has not been reported. Libyostrongylus sp. is an ostrich specific nematode whose parasitism can severely affect the birds. Thus, Libyostrongylus spp. larvae were identified in commercial ostriches in the north region of the state of Rio de Janeiro, Brazil. The EPG was determined and fecal cultivation was performed. The eggs presented typical characteristics of strongylid and were present in five out of six farms. The mean EPG varied from 22 to 2395 and Libyostrongylus spp. prevalence was from 0 to 100%, with adult birds more infected. Two types of infective larvae with tail finishing in a tipped spiny knob were distinguished. The first had a mean length of 848μm (710–1010) with a long sheath tail of about 66μm (52–112). The other had a mean length of 826μm (620–940) with a short, more abruptly ending sheath tail of 32μm (22–40) and a less rounded cephalic end. The differences between these larvae suggest two Libyostrongylus species. [Copyright &y& Elsevier]

In the present work we identify the species of Entamoeba from ostriches (Struthio camelus). The complete sequence of the small subunit ribosomal RNA gene from this organism has been compared with those published for other species of the genus and clear differences have been found. These results confirm previous data which showed differences on parasite morphology and class of host with the other Entamoeba species. Taking all these data together, it can be concluded that the organism from ostriches is a new species whose proposed name is Entamoeba struthionis n.sp. This species probably infects rheas (Rhea americana), but genetic analysis of isolates from this host should be performed to confirm morphological data. Also, comparison of gene sequences with data from other authors on cysts recovered from human stool samples showed the possibility that this amoeba may affect humans. Further studies are needed to determine the risk of transmission of this new species to humans. [Copyright &y& Elsevier]

Libyostrongylus douglassii, a pathogenic trichostrongylid nematode of the ostrich, was recently identified as a potentially important parasite in ostriches on Swedish farms. This parasite is well adapted to the hot and dry climates of sub-Saharan Africa, the natural habitat of the ostrich. The influence of low temperatures in colder climates, such as in Sweden, on free-living stages of L. douglassii is however insufficiently known. In this study, parasite free ostrich faeces were mixed with infective L3-stage larvae of L. douglassii, which had been cultured from eggs obtained from two Swedish farms. Samples of the mixture were placed on a grass surface, and analyses for L3-stage larvae were performed at regular intervals. The results of the study showed that L3-stage larvae may remain alive during a period of at least 97 days on pasture during the winter season in Sweden, even when the temperature within the samples was repeatedly below −0.1 °C, and the air temperature varied between −19.6 and +14.9 °C. It was concluded that L3-stage larvae of L. douglassii probably have the ability to remain viable on pastures during winter in Sweden. [Copyright &y& Elsevier]

Summary: Clinically severe disease was produced in ostriches aged 4 weeks by oral infection with a virulent strain of infectious bursal disease virus (vIBDV), namely strain Faragher 52/70. Four days after infection the birds were humanely killed and tissue samples, including thymus, bursa of Fabricius (BF), brain and kidney were collected for examination. Histopathologically, the thymus and BF showed severe lymphoid depletion and necrosis, while immunolabelling with a polyclonal antibody demonstrated abundant viral antigen. [Copyright &y& Elsevier]