Equine amnionitis and fetal loss: The case definition for an unrecognised cause of abortion in mares

A series of abortions occurred in mares in New South Wales during 2004 that involved similar and unusual findings on post mortem examination of aborted fetuses and fetal membranes. The term Equine Amnionitis and Fetal Loss (EAFL) was developed to describe the condition. This form of abortion had not been previously recognised in Australia. The pathology alone is not specific for EAFL and diagnosis requires demonstration of a combination of certain pathological and bacteriological features. The purpose of this paper is to describe patterns considered consistent with EAFL cases as a working case definition for use by veterinarians and veterinary pathologists in identifying future cases of EAFL. More detailed papers are in preparation to fully describe the epidemiological, histopathological, and microbiological aspects of EAFL.     

Development of Gossypium hirsutum lines with cytoplasmic bollworm tolerance from Gossypium arboreum and Gossypium tomentosum

American cotton [Gossypium hirsutum (L.)] grown in India belongs to the race Latifolium. It is prone to bollworms [Helicoverpa armigera (Hubner), Erias vitella (Fabricius), Pectinophora gossypiella (Saunders)] infestation which causes considerable crop loss. Two breeding lines ‘Bikaneri (BN)‐arboreum (ARB)‐16’ and ‘BN‐tomentosum (TOM)‐277’ are cytoplasmic diverse genetic stocks. They were developed by crossing experimental lines ‘Delta Branch Experiment Station (DES)‐ARB16’ and ‘DES‐TOM277’ (non‐recurrent parents) with G. hirsutum‘BN’ (recurrent parent). Compared with BN these stocks possessed higher amount of gossypol, flavonol and phenol contents in leaves, stem and square. Plants were tolerant to bollworms and inherited comparable agronomic properties (yield, boll weight, plant height, number of monopods and sympods and fibre quality). Cotton breeders can use these lines for breeding cotton resistant to bollworm.     

Improved feed intake and body weight change in sheep treated with dexamethasone at entry into pens or feedlots

Treatment with the synthetic glucocorticoid dexamethasone sodium phosphate increased the feed intake of sheep within 24 h. A single treatment with the longer-acting compound dexamethasone trimethylacetate had a slower effect, but resulted in improved feed intake and enhanced body weight gain over a period of 7 to 14 days. Treatment was effective in sheep housed individually and in sheep penned in groups. The improvement in body weight gain disappeared 15 to 20 days after a single treatment, but in most studies treated sheep had less variability in weight change than untreated sheep at this time. A statistically significant increase in body weight gain was observed in 8 of 11 trials; in the other 3 trials, it appeared that the feed intake of the untreated sheep was already maximal. Wethers treated with dexamethasone trimethylacetate on arrival at an assembly point for live export arrived in the Middle East 23 days later with a lower mean weight loss, partly because fewer sheep lost a significant amount of weight.     

Identification and Pathogenicity of Pseudomonas aeruginosa DJ1990 on Tail and Fin Rot Disease in Spotted Snakehead

Tail and fin rot disease (TFRD) is a big issue in the production of spotted snakehead, Channa punctata Bloch. The aims of the present study were to isolate and identify the bacterial pathogen causing TFRD, to detect histopathological changes in tissues (fin, tail, liver, and kidney), and to ascertain the antibiotic sensitivity pattern of the isolate. Out of six bacterial isolates, only the isolate DJ1990 was found to be the causal candidate of TFRD in C. punctata. Identical histopathological changes were detected in tail, fin, liver, and kidney under light and scanning electron microscope in both collected diseased fish and artificially infected fish. The isolate was identified as Pseudomonas aeruginosa strain DJ1990 (National Center for Biotechnology Information Ace. No. KX709967) based on the biochemical characterization tests and 16S rDNA sequence‐based phylogeny analysis. Artificial challenge test demonstrated that the strain DJ1990 was highly virulent (100% mortality at 48 h of postinjection period at the concentration of 1.5 × 10⁷ CFU/g of body weight) for C. punctata. The isolate exhibited sensitivity to the broad‐spectrum antibiotics but was resistant against aztreonum. To the best of our knowledge, this is the first report of P. aeruginosa as a TFRD‐causing candidate in C. punctata.     

Effect of bandaging on second intention healing of wounds of the distal limb in horses

Objective   To evaluate the effect of a non-occlusive dressing incorporated in a 3-layer bandage on second intention healing of wounds of the distal portion of the limb.
Study Design   Untreated wounds in 33 adult horses used in four studies using the same wound-healing model conducted over 5 years.
Methods   Standardised, full-thickness wounds were made in the skin overlying the dorsomedial aspect of the mid-metacarpus; 17 horses were bandaged with a non-occlusive dressing covered by gauze-coated cotton wool that was compressed with adhesive tape; 16 horses were left unbandaged. Wounds were photographed weekly for 9 weeks and the images were analysed electronically.
Results   There were significant effects associated with bandage (P < 0.0001), week (P < 0.001), and bandage by week interaction (P < 0.0001). There was no difference in wound area at the first time-point after wound creation (P = 0.38). After week 1, there was a difference between bandaged and unbandaged wounds in wound area at each measurement until the end of the study. Bandaged wounds showed greater and more prolonged retraction. Unbandaged wounds retracted for 2 weeks before beginning to contract, whereas bandaged wounds continued to retract for 3 weeks. In bandaged wounds excess granulation tissue required regular trimming, but not in unbandaged wounds. There was no difference between groups in the total days to healing or the overall rate of healing.
Conclusions   These results should be treated with caution until validated with contemporaneous, controlled studies. Covering a wound with a non-occlusive dressing in a 3-layer bandage led to greater wound retraction, modulated the rate of wound contraction and promoted excessive granulation tissue. If excessive granulation tissue is excised regularly, bandaging has no effect on total time to healing.     

Narrow sense heritability estimates of bacterial leaf spot resistance in pseudo F2 (F1) population of mulberry (Morus spp.)

Bacterial leaf spot incited by Xanthomonas campestris pv. mori is a devastating foliar disease of mulberry reported globally. Host plant resistance is the most sustainable and economic control measure but so far unexplored. Highly heterozygous plant behaviour and scant genetic information of bacterial leaf spot resistance limits a targetted breeding approach in mulberry. In the present research eight pseudo-F₂(F₁)full-sib progenies derived from selected resistant and susceptible sources were evaluated symptomatically for bacterial leaf spot resistance under natural disease occurrence in 2008 and 2009. Significant variation for bacterial leaf spot resistance was observed in the parents and progenies. Broad sense heritability estimate (0.9) indicates that selection of resistant genotypes can be useful for exploitation in future advanced breeding programs for mulberry. High narrow sense heritability estimates (0.76)[2008] and (0.79)[2009] suggest additive gene effects for the disease resistant trait. The continuous frequency distribution of diseases severity across the progenies indicates that bacterial leaf spot resistance in mulberry may be inherited quantitatively.     

Action of the fungicide tridemorph on the glucose,lactate and succinate dehydrogenase activities of some tridemorph-sensitive and -resistant bacteria

The systemic morpholine fungicide tridemorph, which is known to exert its antifungal action through inhibition of ergosterol biosynthesis, can also inhibit the growth of organisms which are incapable of sterol biosynthesis. It was found to inhibit strongly glucose and lactate dehydrogenase activities in cultures of four Gram( +) bacteria, Rhodococcus sp. AK 1, Bacillus cereus Frankland & Frankland, Bacillus subtilis (Ehrenberg) Cohn, Nocardia asteroides and a Gram(?) bacterium, Rhizobium leguminosarum. Growth of these bacteria was inhibited by tridemorph at concentrations between 7 and 60 mg litre^?1. In contrast, similar dehydrogenase activities in other Gram(?) organisms, Escherichia coli Cast. & Chalm. and Azotobacter vinelandii, which showed no growth inhibition at 200 mg litre ^?1 tridemorph, were either not inhibited or inhibited only slightly. Similarly, succinate dehydrogenase activity in Rhodococcus sp. AK 1 was more strongly inhibited by tridemorph than that in E. coli. In cell-free extracts of Rhodococcus sp. AK1 and E. coli, lactate dehydrogenase activity was also inhibited by tridemorph to a much greater extent in the sensitive strain (63%) than in the resistant ones (8%).     

Histopathology of respiratory organs of certain air-breathing fishes of India

Air-breathing fishes have evolved bimodal respiratory mechanisms for exploitation of water (through gills and highly vascularized skin) as well as atmospheric air (through aerial respiratory organs, ABO). Mucous cells in these respiratory organs of variously stressed fishes exhibit periodic fluctuations in their density and staining properties. The main types of damage in the gills include congestion of blood capillaries (BLCs), periodic lifting and sloughing of respiratory epithelia of the secondary lamellae causing haemorrhage, extensive fusion of secondary lamellae and hyperplasia of the respiratory epithelia due to uncontrolled regeneration leading to asphyxiation, altered excretion, and death of the fish. Haemolysis has also been observed following lead exposure. The damage in the ABO of Heteropneustes fossilis includes sloughing of the epithelial cells, leading to haemorrhage causing decreased red blood corpuscles density and degeneration of the secondary gill lamellae with reduced respiratory area. Subsequent hyperplasia of the respiratory epithelia and fusion of gill lamellae increase the respiratory barrier distance. The BLCs often bulge out and protrude into the lumen, bringing blood nearer to air. The ladder-like pillar cell (PLC)-BLC components of the gill lamellae frequently collapse. Damage to the ABO of Channa striata is less severe. Often haemorrhaging due to bursting of extensively stretched BLCs causes aerial respiratory failure. Chloride cells of the ABOs also show hyperplasia. While the highly mucogenic epidermis of C. striata shows less damage, the epidermis of Clarias batrachus and H. fossilis shows severe wear and tear, sloughing, and haemorrhage. Side-by-side regeneration continues, causing altered histomorphology of the epidermis. The different gland cells also show periodic fluctuations in their density and staining. The dermis also shows severe damage with loosening of their connective tissue fibres. These fibres give stronger reactions for sulfated mucin that not only retain additional water molecules for continuance of skin breathing, but also bind the toxic ambient pollutants.