Candida albicans infection in free-living populations of hihi (stitchbird; Notiomystis cincta)

Abstract

AIM: To describe the occurrence of candidiasis in hihi (stitch-bird; Notiomystis cincta) nestlings, and investigate the carriage and impact of Candida albicans infection in a free-living population of hihi.

METHODS: Mortality of nestlings was investigated in a reintroduced population of the endangered, endemic hihi at Zealandia: Karori Sanctuary, Wellington, New Zealand. Oral and faecal samples were collected from live hihi nestlings, for microbiological examination, between October 2008 and April 2009. All hihi that died and could be recovered were submitted to the New Zealand Wildlife Health Centre (NZWHC) at Massey University, for post-mortem examination. The results were compared with data obtained retrospectively from the National Wildlife Mortality (NWM) database for two other reintroduced populations of hihi on Mokoia and Tiritiri Matangi Islands.

RESULTS: Fifty chicks fledged from 82 eggs hatched during the 2008–2009 breeding season at Zealandia: Karori Sanctuary. Thirty-four live nestlings were sampled from 11 nests, and C. albicans was isolated from gastrointestinal swabs of 13 live nestlings from four nest sites. Eight (62%) of those nestlings survived to fledge, compared with 17/21 (81%) of those that tested negative (p=0.254; Fisher's exact test). Of the 32 hihi nestlings that died during the period of the study, 25 were recovered for necropsy. Histopathological examination revealed candidiasis was a factor in the deaths of four nestlings. An adult hihi that died during the period of the study at Zealandia: Karori Sanctuary was also found to have candidiasis. Retrospective analysis of data from the NWM database revealed candidiasis was also a factor in the deaths of five nestlings aged between 1 and 10 days from Mokoia Island, and of three nestlings <5 days old and one adult from Tiritiri Matangi Island.

CONCLUSIONS: Candida albicans was isolated from 38% of hihi nestlings sampled in this study, and vertical transmission of this organism from parent to offspring is likely to occur. Some colonised nestlings developed ventriculitis associated with Candida spp., but survival to fledging was not significantly different between nestlings that tested positive or negative, although the fate of birds following fledging was unknown.     

Seasonal variation in the hip score of dogs as assessed by the New Zealand Veterinary Association Hip Dysplasia scheme

Abstract

AIM: To determine whether there is a seasonal variation in the phenotypic hip score of dogs born in New Zealand as assessed by the New Zealand Veterinary Association (NZVA) canine hip dysplasia (CHD) scheme.

METHODS: Data from dogs born in New Zealand between 1988 and 2009 that have been scored for CHD were retrospectively evaluated for the effect of month of birth on radiographic phenotype. Data included both the total score and the subtotal score, comprising Norberg's angle, the subluxation score and changes to the cranial acetabular edge, for each dog. Datasets were created for all breeds combined and for the four most populous breeds using the scheme (German Shepherd dog, Labrador Retriever, Golden Retriever and Rottweiler) and stratified according to month of birth and season. Due to the skewed nature of the data, a Kruskal–Wallis Rank Sum test was used to test for statistical significance. Additionally, χ² analysis was performed using the median of each dataset (proportion above/below the median). The null hypothesis was that there would be no effect of month of birth, and hence seasonality, on hip phenotype for dogs born and scored in New Zealand by the NZVA.

RESULTS: For all breeds combined, month of birth had an effect on total and subtotal NZVA CHD scores (p<0.001) with a lower total hip score in the autumn months of March and April than other months. When individual large breed data were analysed, there was an effect of month of birth on total and subtotal scores for the Labrador Retriever and the Rottweiler (p≤0.05), but not the German Shepherd dog or Golden Retriever breeds.

CONCLUSIONS: Being born in the autumn was associated with a protective effect on hip phenotype in some breeds. These results suggest that weather and/or another seasonal factor may have a significant environmental effect on the phenotype of the coxofemoral joint.

CLINICAL RELEVANCE: The protective effect of being born in autumn suggests that a decreased level of exercise during subsequent development over winter may positively impact on final coxofemoral joint conformation. Whilst statistically significant, the magnitude of the sparing effect is not likely to be clinically relevant. However, this study, in concert with other studies, may suggest that the effects of exercise can be manipulated to improve hip phenotype.     

Immunohistochemistry Diagnosis of an Ovarian Dysgerminoma in One Bitch

An ovarian enlargement (diameter, 8 cm) was identified and surgically excised from a 5-year-old female dog. Microscopic examination of the multinodular neoplasm revealed sheets of polygonal neoplastic cells with large nuclei, frequent mitosis, necrosis and haemorrhage. Immunohistochemically, the neoplastic cells were positive for vimentin and alkaline phosphatase but were negative for CD3, CD79a, cytokeratin, alpha-fetoprotein, inhibin-α and S-100. The histopathological diagnosis of the mass was unilateral ovarian dysgerminoma.     

Identification of Sperm-Head Morphometric Subpopulations in Iberian Red Deer Epididymal Sperm Samples

Computer-assisted sperm morphometry analysis (CASMA) was used in this study to identify sperm morphometric subpopulations in Iberian red deer epididymal sperm samples. Epididymal sperm samples were collected from 37 mature stags and were divided. One portion was diluted in a Tris–citrate–egg yolk medium. A microscope slide was prepared from single extended sperm samples prior to freezing. The remainder of each sample was frozen in nitrogen vapours using a conventional protocol. After thawing, sperm smears were prepared as described for extended samples. All slides were air-dried and stained with Hemacolor^®. The sperm-head dimensions for a minimum of 145 sperm-heads were analyzed from each sample by means of the Sperm-Class Analyser^®, and the mean measurements recorded. Each sperm-head was measured for four primary sperm-head parameters, and five parameters of head shape. All sperm morphometric parameters evaluated were placed in a statistical database and a multivariate cluster analysis was performed. The clustering analyses, based on 10 867 individual spermatozoa, revealed the existence of three subpopulations (SP₁, SP₂, SP₃) of spermatozoa with different morphometric characteristics (p  <  0.001). The proportion of spermatozoa present in any of the three subpopulations remained constant (p  >  0.05) through the cryopreservation process. Pre-freeze and post-thaw sperm quality was in vitro evaluated by microscopic assessments of individual sperm motility and of plasma membrane and acrosome integrities. In conclusion, our results show that applying the CASMA techniques and multivariate cluster analyses, it was possible to determine that three subtle subpopulations of spermatozoa with different morphometric characteristics coexist in red deer semen.     

Identification and characterization of pathogens associated with root rot of winter peas grown under organic management in Germany

Root rots are limiting factor for pea production worldwide. This disease is caused by a pathogen complex and the role of single pathogens is unclear. This study aimed at identifying pathogens involved in a root rot of organically grown field pea in Germany, and establishing their importance in the disease complex. The potential of yard waste compost to suppress the diseased was also studied. Average disease severity index was similar in 2010 and 2011 (DI of 4.56 to 4.59, respectively) but it increased in 2012 to DI 5.8. Peyronellaea pinodella was most frequently isolated pathogen, with isolation frequency from 86%, 73% and 86% in 2010, 2011 and 2012, respectively. In addition, Didymella pinodes, Fusarium solani f. sp. pisi, F. oxysporum f. sp. pisi and F. avenaceum were the main fungi recovered from pea roots. In pathogenicity test all of the tested pathogens caused weak symptoms on the pigmented winter variety EFB33 and moderate to severe symptoms on the white flowering summer variety Santana. F. avenaceum was the most aggressive pathogen on Santana with DI of 7.4 followed by P. pinodella with DI of 5.7. The high aggressiveness combined with the wide host range highlights the possibility of F. avenaceum emerging as potential risk for organic crop rotation. High levels of resistance of EFB33 against all pathogens shows the potential of this variety to serve as a resource in further research for identification and development of new sources of resistance against root rot diseases of pea.     

Seed health of organic peas and faba beans and its effects on the health of the harvested grains

Journal of Plant Diseases and Protection - A survey was conducted in Germany during 2009–2012 on seed health of organic pea and faba beans and their harvested progeny seed on up to 32 organic...     

Antisperm antibodies in repeat‐breeding cows: Frequency,detection and validation of threshold levels employing sperm immobilization,sperm agglutination and immunoperoxidase assay

Antisperm antibodies have been found in repeat‐breeding(RB) cows, and those causing agglutination and/or immobilization of sperm are considered to be closely related to unexplained infertility. However, a standard protocol for identifying antisperm antibodies (ASA) in cattle is not validated. Therefore, an investigation was undertaken to evaluate sperm immobilization (SIT), sperm agglutination (SAT) and immunoperoxidase (IPT)assays for detection of ASA in serum and their respective threshold levels for confirmation. Animals (heifers, normally breeding, repeat‐breeding and pregnant animals) that were free from IBR, brucellosis and uterine infections (screened by clinical examination) were included in the study. Sperm agglutinating, sperm immobilizing and antisperm antibodies evaluated by respective assay were significantly higher (p < .05) in RB cows compared to other groups. The SIT assay was able to identify 61% of RB caused by ASA, more than those employing SAT and IPT. Furthermore, a dilution rate of 1:5 and 1:80 (confirms 59.0 and 57.0% RB+ve)were sufficient to diagnose ASA by SAT and IPT, respectively. Results indicate the presence of __12.6% clumped spermatozoa and __ 2.6%(cut‐off value) peroxidase‐positive spermatozoa at 1:5 and 1:80 dilutions diagnosed with SAT and IPT, respectively, may be considered as repeaters arising out of ASA. Furthermore, study also showed the presence of lower incidence of ASA positivity in other groups of animals (heifer<normal breeder<pregnant animals) compared to repeaters. Study results show that although IPT is more specific and accurate but SAT and SIT are comparatively simple and cost‐effective assays suitable for detecting ASA under field conditions and thus can be recommended for screening of repeaters.     

Effects of fertilizers and plant strengtheners on the susceptibility of tomatoes to single and mixed isolates of Phytophthora infestans

Three organic fertilizers, Horn meal, i.e., BioFeed Basis and Bio-ILSA, and three plant strengtheners, i.e., Alfalfa extract, PEN and QUALITY were compared to chemical fertilizer (NPK) application and the synthetic inducer BABA (DL-3-amino-butyric acid) for reactions of leaf disks of six different tomato cultivars to three isolates of Phytophthora infestans. Late blight severity was significantly reduced on plants fertilized with Bio-ILSA and BioFeed Basis compared to plants fertilized with Horn meal and chemical fertilizer. There were no interactions between fertilizers and isolates or between fertilizers and cultivars. All plant strengtheners significantly reduced susceptibility of all tomato cultivars. However, effects were isolate and tomato cultivar specific. The reductions in area under the disease progress curve compared to the water control for the different tomato cultivars and isolates were 23–78%, 21–77%, 17–66%, and 37–100% for Alfalfa extract, PEN, QUALITY and BABA, respectively. Similar, but somewhat smaller reductions were observed for sporulation capacity. The plant strengtheners were more effective in controlling disease on plants challenged with isolate mixtures than on plants challenged with single isolates. BABA performed significantly better than the plant strengtheners in 65% (i.e., 34 out of 54) of the tested cultivar-isolate combinations, when single isolates were used. When two isolates were mixed, the percentage was reduced to 45% (25 out of 54 cases) and to 33%, (6 out of 18 cases) with a mixture of three isolates.     

Effects of Egg Yolk and Cooling Rate on the Survival of Refrigerated Red Deer (Cervus elaphus hispanicus) Epididymal Spermatozoa

Egg yolk is a common component to sperm refrigeration for most of the deer species, the role of which is to protect sperm membranes against cold shock. In addition, there have been many studies of conservation of ejaculated semen from stags, but few have been reported for epididymal spermatozoa. This work was designed to investigate the combined effects of cooling rates (slow: 0.23 degrees C/min vs rapid: 4.2 degrees C/min) from room temperature to 5 degrees C, and egg-yolk concentration (0, 5 or 20%) in the extender on the survival of Iberian red deer epididymal spermatozoa refrigerated at 5 degrees C. Heterospermic sperm samples were diluted to a final sperm concentration approximately 400x10(6) sperm/ml with a Tris-citrate-fructose (TCF)-egg-yolk diluent. Sperm quality was in vitro judged by microscopic assessments of individual sperm motility [sperm motility index (SMI)], and of plasma membrane (hypo-osmotic swelling test) and acrosome (NAR) integrities. Our results first showed that the presence of egg yolk in the extender significantly improves (p=0.01) the viability and sperm motility after sperm dilution. In addition, acrosome and plasma membrane integrities post-refrigeration did not differ significantly between cooling procedures; however, the SMI differed significantly between cooling procedures (slow: 46.6% vs rapid: 50.0%; p=0.01). Our results also showed that sperm quality was significantly (p<0.01) affected by the combined effects of egg-yolk concentration and cooling procedure, being rapid cooling with 20% of egg yolk the most suitable combination for epididymal sperm refrigeration. In conclusion, egg-yolk improved red deer epididymal spermatozoa characteristics after dilution. Rapid cooling protocol using TCF with 20% egg-yolk significantly improved sperm motility of red deer epididymal spermatozoa after cooling.