Campylobacter species in dogs and cats and significance to public health in New Zealand : a thesis in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Veterinary Science at Massey University, Palmerston North, New Zealand

Campylobacter spp. are a major cause of bacterial gastroenteritis in people in the developed world, including New Zealand. Many sources and transmission routes exist, as these bacteria are common in animals and the environment. C. jejuni is most frequently associated with poultry whereas C. upsaliensis and C. helveticus with dogs and cats, respectively. Published data on Campylobacter in dogs and cats in New Zealand and on the pathogenic potential of C. upsaliensis and C. helveticus are very limited. This thesis investigated the prevalence of Campylobacter spp. in household dogs and cats in Manawatu region, New Zealand, and in raw meat pet food commercially available in Palmerston North, New Zealand. Five Campylobacter spp. were isolated and the prevalence rates were significantly influenced by the culture methods used. C. upsaliensis and C. helveticus were most frequently detected from dogs and cats, respectively and C. jejuni in pet food samples. An expanded panel of culture methods was used to screen working farm dogs and their home-kill raw meat diet in Manawatu. This study reported three Campylobacter spp. and Helicobacter winghamensis as being isolated from dogs for the first time. The culture methods were again shown to bias the prevalence estimates. The isolates of C. upsaliensis and C. helveticus from the household pets study and C. hyointestinalis from locally farmed deer were used in a study to investigate the analytical sensitivity in spiked human clinical faecal samples using the ProSpecTTM Campylobacter Microplate Assay test that was developed for detection of C. jejuni/coli. The results showed the ability of the test to detect all three species and showed the influence of bacterial dose, faecal consistency and of the individual faecal samples on the test results. Further studies investigated the pathogenic potential of C. upsaliensis and C. helveticus in comparison to C. jejuni using an insect model of disease, Galleria mellonella, and whole-genome analyses, respectively. The results of the survival analysis in the G. mellonella study indicated that C. upsaliensis and C. helveticus have pathogenic potential, but to a lesser extent than C. jejuni. Additionally, several variables of experimental design were shown to significantly influence estimates of hazard rates in survival analysis. Whole genome analyses also showed indications of the pathogenic potential of C. upsaliensis and C. helveticus relative to C. jejuni, and how it varies between and within species in association with the core and accessory genomes, functional gene content profiles, and documented and predicted pathogenic proteins. This thesis has furthered our understanding of the epidemiology, detection, and pathogenicity of Campylobacter spp. in dogs, cats and humans, and confirmed raw meat animal food as a potential source of Campylobacter spp. for both people and animals

KVALITETA MESA LUBINA TIJEKOM POHRANE NA LEDU

Cilj ovog rada bio je odrediti održivost mesa lubina tijekom njegove pohrane na ledu u trajanju od 12 dana pracenjem senzornih, fizikalno-kemijskih i mikrobioloških parametara kakvoce i higijenske ispravnosti. U tu je svrhu pretraženo 30 lubina 2., 4., 6., 9. i 12. dana pohrane na ledu na 3º C. Senzorna ocjena kvalitete ocijenjena je Quality Index Method testom (QIM) izra!enom za lubina, Dicentrarchus labrax (Icelandic Fisheries Laboratories) i Market testom. Uzorci ribe su pretraženi na ukupni broj aerobnih mezofilnih bakterija, psihrotrofnih bakterija i Pseudomonas spp. Tako!er su mjerene vrijednosti pH i kolicina amonijaka. Kolicina amonijaka povecavala se tijekom pohrane ribe i tako pratila promjenu njezinih senzornih svojstava, te su uzorci ribe na kraju našeg istraživanja s 16,1 mg% amonijaka, ocijenjeni kao riba ugrožena od kvarenja. Usporedo s porastom odstupanja od svojstvenoga izgleda i mirisa svježega lubina rastao je i broj psihrotrofnih bakterija i Pseudomonas spp.The goal of this work was to determine the sustainability of the sea bass meat during its storage on ice in the period of twelve days by following sensory, physical- chemical and microbiological parameters of quality and hygienic safety. Thirty sea basses were researched for that goal on the 2nd, 4th, 6th, 9th and 12th day of storage on ice at 3º C. Sensory grade of quality was evaluated by Quality Index Method test (QIM) created for sea bass, Dicentrarchus labrax (Icelandic Fisheries Laboratories) and Market test. Fish samples were researched on the total count of aerobic mesophyllic bacteria, psychotrophic bacteria and Pseudomonas spp. There were also measured pH- values and the quantity of ammonia. The quantity of ammonia was increasing during the storage of fish and in that manner it was following its sensory characteristics, so the fish samples at the end of our research were evaluated as fish at risk of rotting with 16.1 mg% of ammonia. Together with the increase of aberration from the characteristic appearance and smell of fresh sea bass, the number of psychotrophic bacteri

KVALITETA MESA LUBINA TIJEKOM POHRANE NA LEDU

Cilj ovog rada bio je odrediti održivost mesa lubina tijekom njegove pohrane na ledu u trajanju od 12 dana pracenjem senzornih, fizikalno-kemijskih i mikrobioloških parametara kakvoce i higijenske ispravnosti. U tu je svrhu pretraženo 30 lubina 2., 4., 6., 9. i 12. dana pohrane na ledu na 3º C. Senzorna ocjena kvalitete ocijenjena je Quality Index Method testom (QIM) izra!enom za lubina, Dicentrarchus labrax (Icelandic Fisheries Laboratories) i Market testom. Uzorci ribe su pretraženi na ukupni broj aerobnih mezofilnih bakterija, psihrotrofnih bakterija i Pseudomonas spp. Tako!er su mjerene vrijednosti pH i kolicina amonijaka. Kolicina amonijaka povecavala se tijekom pohrane ribe i tako pratila promjenu njezinih senzornih svojstava, te su uzorci ribe na kraju našeg istraživanja s 16,1 mg% amonijaka, ocijenjeni kao riba ugrožena od kvarenja. Usporedo s porastom odstupanja od svojstvenoga izgleda i mirisa svježega lubina rastao je i broj psihrotrofnih bakterija i Pseudomonas spp.The goal of this work was to determine the sustainability of the sea bass meat during its storage on ice in the period of twelve days by following sensory, physical- chemical and microbiological parameters of quality and hygienic safety. Thirty sea basses were researched for that goal on the 2nd, 4th, 6th, 9th and 12th day of storage on ice at 3º C. Sensory grade of quality was evaluated by Quality Index Method test (QIM) created for sea bass, Dicentrarchus labrax (Icelandic Fisheries Laboratories) and Market test. Fish samples were researched on the total count of aerobic mesophyllic bacteria, psychotrophic bacteria and Pseudomonas spp. There were also measured pH- values and the quantity of ammonia. The quantity of ammonia was increasing during the storage of fish and in that manner it was following its sensory characteristics, so the fish samples at the end of our research were evaluated as fish at risk of rotting with 16.1 mg% of ammonia. Together with the increase of aberration from the characteristic appearance and smell of fresh sea bass, the number of psychotrophic bacteri

Vrućica nepoznata uzroka u pasa: 50 slučajeva

Although in veterinary medicine the term “Fever of unknown origin” (FUO) is still liberally used for any febrile patient where no diagnosis has been set after routine diagnostics, the term “true FUO” should be assigned to those cases in which no aetiology is found after extensive diagnostics. The aim of this study was to investigate the occurrence of FUO in dogs, to research the structure of the FUO population, as well as to explore clinical signs and their duration, and the prior treatment and incidence of different diagnoses and their outcomes. Also, this study was conducted in order to explore the amount of diagnostic procedures (with their effectiveness) required to reach a final diagnosis with the intention of helping design and prioritize diagnostics of FUO in dogs in Croatia. Final diagnosis was reached in 94% (47/50) of dogs with a total of 626 diagnostic procedures used. Immune-mediated diseases occurred most frequently (56%), followed by infectious diseases (24%), neoplastic diseases (10%) and congenital diseases (4%), with only 6% of “true FUO”. Body temperature ranged between 39.6 °C and 42.0 °C. The most common symptoms were nonspecific (anorexia and lethargy in 88%, pain in 78%, and gait disorders in 60%). The most frequent test performed was hematology while hemoculture was performed the least. Cytology and/or pathohistology were the most effective tests in achieving the final diagnosis (76.32%). The duration of clinical signs before the diagnosis/ proper treatment was 4-1825 days. The outcome was favorable in 62%, unfavorable in 32% and unknown in 6%.Premda termin vrućica nepoznatog uzroka (VNU) u veterinarskoj medicini još uvijek nema točno određenu definiciju ni kriterije klasifikacije, te se vrlo često liberalno upotrebljava u febrilnih pacijenata u kojih nije postavljena egzaktna dijagnoza nakon rutinske dijagnostičke obrade, VNU bi trebalo rezervirati za one pacijente u kojih ni nakon opsežne dijagnostike nije otkriven uzrok, tj. postavljena konačna dijagnoza. Ciljevi ovog istraživanja bili su istražiti pojavnost VNU-a kao i različitih dijagnoza u pasa s vrućicom, kliničke simptome i njihovo trajanje do postavljanja dijagnoze i početka ciljanog liječenja, te ishode liječenja, odnosno bolesti. Također, svrha ovog istraživanja bila je istražiti prosječan broj dijagnostičkih postupaka (i njihovu učinkovitost) potrebnih za postavljanje konačne dijagnoze, s ciljem kreiranja dijagnostičkog plana u pasa s VNU-om u Hrvatskoj. U 94 % pasa (47/50) postavljena je konačna dijagnoza pomoću ukupno 626 dijagnostičkih postupaka. Najčešće su bile zastupljene imunosno posredovane bolesti (56 %), zatim infekcijske (24 %), neoplastične (10 %) i kongenitalne (4 %), dok je pravi VNU bio zastupljen u samo 6 % slučajeva. Tjelesna temperatura kretala se od 39,6 do 42,0 °C. Najčešći su klinički znakovi bili nespecifični (gubitak apetita i letargija u 88 %, bolnost u 78 % te poremećaji kretanja u 60 % slučajeva). Najčešći je dijagnostički postupak bila hematološka pretraga, a najrjeđi hemokultura. Citološka i/ili patohistološka pretraga pokazale su se najučinkovitijima u postavljanju konačne dijagnoze (76,32 %). Trajanje simptoma do postavljanja dijagnoze, odnosno početka adekvatnog liječenja iznosilo je od 4 do 1825 dana. Ishod je u 62 % pasa bio povoljan, u 32 % nepovoljan, dok je u 6 % ostao nepoznat

Stunning of fish

U radu je opisan utjecaj različitih metoda omamljivanja i usmrćivanja riba na kakvoću njihovog mesa. Pojedine, manje humane metode omamljivanja indiciraju sekundarni stresni odgovor u riba, koji za posljedicu ima bržu razgradnju ATP-a u mišićju, brži pad pH, te brži nastup i otpuštanje mrtvačke ukočenosti. Nadalje, stres nastao prilikom omamljivanja i usmrćivanja riba može imati i negativan utjecaj na teksturu mesa, kao i na održivost. Odabir prikladne metode ovisi i o vrsti i veličini ribe.The paper describes the influence of different methods of stunning and killing of fish on the meat quality.Selection of adequate stunning method is of utmost importance, from the aspect of both fish welfare and its meat quality. Some, less humane methods of stunning induce secondary stress in fish, resulting in more rapid disintegration of ATP in muscles and drop in pH value, as well as in more rapid onset and alleviation of rigor. Furthermore, the stress induced by stunning and killing of fish ca nhave a negative impact on the texture and shelf life of meat. Choice of adequate method depends also on the size and species of fish

Seasonal antioxidant and biochemical properties of the Northern Adriatic Pecten jacobaeus

The present work is the first study of Mediterranean scallop (Pecten jacobaeus) biochemical properties, antioxidant defenses, and free radical scavengers during the yearly seasons in the Northern Adriatic, off Istria. Scallop nutrient reserves (glucose, triglyceride, and cholesterol) in four tissues under examination were positively correlated and were predominant in digestive gland and gonad. The muscle energy maxima were in correlation with the maximum fall gonosomatic index (GSI), when diatoms and coccolithophorids thrive. The decrease of GSI in summer might be related to the spawning or resorption of gametes. Summer also revealed elevated levels of glucose in gonad and digestive gland, while muscle glucose and cholesterol significantly varied in spring vs. winter samples. In relation to the diatom seasonal abundance, carotenoids, namely astaxanthin peaks were found in digestive gland, which, being stimulators of calcium transport over cell membranes, could have contributed to the high digestive gland levels of calcium in winter. In winter, total antioxidative status (TAS) of scallop tissues was 3-fold higher than in other seasons, particularly in digestive gland, having a significant correlation with magnesium, a regulatory tool in oxidative processes. The winter maxima of TAS and thiobarbituric acid reactive substances TBARS in relation to summer maxima of glutathione peroxidase and superoxide dismutase in digestive glands indicate to a decrease in antioxidant defense during cold months, and are related to the accumulation of lipid peroxidation products (such as malondialdehyde) in digestive gland of scallops. Although the increased susceptibility to oxidative stress could be attributed to winter temperature, other factors such as the gonad maturation, availability of food supply, and salinity might counteract that effect. The seawater alterations of salinity, temperature and water quality are in relation to the river Po influx, which is very likely to influence the physiological and biochemical responses of scallops in the Northern Adriatic

Identification of environmental aquatic bacteria by mass spectrometry supported by biochemical differentiation

In this study, the purposefulness of using the API20E biochemical identification system as a supportive tool for enhancing the discrimination of environmental bacteria by MALDI-TOF MS method was evaluated. The identification results of MALDI-TOF MS and API20E for 321 Gram-negative strains isolated from the riverine freshwater and its sediment, and from the tissues of fish from the same water body were compared. Of 190 isolates identified with probable to highly probable species-level identification, and secure genus to probable species identification, 14 isolates (7.37%) had identification score over 2.300, and from the same group 19 isolates (10%) had excellent or very good identification to the genus by API20E system. With regard to agreement at genus level, out of 231 strains with genus designation available by API20E at any level of identification reliability, MALDI-TOF MS genus identification agreed in 163 (70.6%) strains. Of these, 135 (82.8%) were Aeromonas species and the remaining isolates belonged to 7 different genera. Although API20E resulted in frequent misidentification due to a limited profile index, its individual biochemical reactions might contribute to overall characterization of isolates. For example, for all reliable A. hydrophila strain identifications with MALDI-TOF MS, ONPG, GLU and OX reactions were unarguably positive for all fish and water/sediment isolates, whereas only fish isolates yielded additional 100% positive TDA and VP reactions. Thus, after initial identification with MALDI-TOF MS, environmental isolates with lower identification scores should be further analyzed. Before commencing confirmatory testing with nucleic acid-based methods, biochemical API20E tests could be applied as a purposeful and inexpensive identification support in targeting better identification accuracy. In this study, this was particularly evident with A. hydrophila, Chryseobacterium sp. and Pseudomonas sp. This identification strategy could significantly resolve methodological and cost-related shortcomings frequently occurring with large number of environmental isolates