Evaluation of non-chemical seed treatment methods for the control of Alternaria dauci and A. radicina on carrot seeds

The current study was initiated to evaluate the efficacy of physical methods (hot water, aerated steam, electron treatment) and agents of natural origin (resistance inducers, plant derived products, micro-organisms) as seed treatments of carrots for control of Alternaria dauci and A. radicina. Control of both Alternaria species by seed treatment with the resistance inducers was generally poor. Results were also not satisfactory with most of the formulated commercial micro-organism preparations. Based on the average of five field trials, one of these, BA 2552 (Pseudomonas chlororaphis), provided a low but significant increase in plant stand. Among the experimental micro-organisms, the best results were obtained with Pseudomonas sp. strain MF 416 and Clonostachys rosea strain IK726. A similar level of efficacy was provided by seed treatment with an emulsion (1%) of thyme oil in water. Good and consistent control was generally achieved with the physical methods aerated steam, hot water and electron treatment. Aerated steam treatment was, apart from the thiram-containing chemical standard, the best single treatment, and its performance may at least partially be due to extensive pre-testing, resulting in dosages optimally adapted to the respective seed lot. In some of the experiments the effect of the hot water treatment, which was tested at a fixed, not specifically adapted dosage, was significantly improved when combined with a Pseudomonas sp. MF 416 or C. rosea IK726 treatment. The results are discussed in relation to the outcome of experiments in which the same seed treatment methods and agents were tested in other seed-borne vegetable pathosystems.     

Optimal harvesting of farmed Atlantic salmon at two cohort management strategies and different harvest operation restrictions

Abstract

The main harvest planning problem in commercial fish farms is to determine the best time‐sequence of harvesting different fish cohorts in order to maximize the overall farm profit. Due to both annual and fish‐size variations in market prices, future forecasts of fish growth and size distribution are required to optimize harvest plans. Two management strategies for harvesting size‐structured fish cohorts are considered. The first strategy allows the fish farmer, at any time, to size‐grade, harvest and sell the most profitable fish sizes from the standing stock. The second strategy allows the fish farmer to harvest and sell a fish batch with similar size distribution as that of the standing stock. In this paper, two size‐structured fish growth models have been built to fit the two management strategies. The growth models are integrated in a multiperiod linear programming model that optimizes the harvest outputs for each of the two management strategies. Model outputs demonstrate clearly that it is more profitable to size‐grade fish prior to harvest compared to harvesting a batch of fish with similar size distribution to that of the standing stock. Five different harvest operations constraints have been identified for commercial salmon farming. The decrease in profitability of fish farming is shown for a variety of harvest operation constraints.     

Effects of cimaterol on rabbit growth and myofibrillar protein degradation and on calcium-dependent proteinase and calpastatin activities in skeletal muscle

The objectives of this study were to examine effects of a beta-adrenergic agonist (cimaterol) on growth and muscle development in rabbits and to examine cimaterol's effects on myofibrillar protein degradation (MPD) and on activities of several proteolytic enzymes including the calcium-dependent proteinases (CDP). Twelve New Zealand White rabbits were assigned to either control diets or to diets containing cimaterol for 35 d, after which they were killed and effects on performance and tissue weight gains were determined. Urine was collected from d 21 through 28 from each rabbit for assessment of N tau-methylhistidine (NMH) excretion. Cimaterol increased rates of gain, efficiency of gain and skeletal muscle weights. Enhancement in muscle weight was associated with an increase in total DNA and with a reduction in NMH. Cimaterol did not affect activities of cathepsin B, cathepsin D or neutral serine proteinase, but it reduced activities of the millimolar and micromolar forms of the CDP by 58 and 57%, respectively, and it reduced activity of the inhibitor of the CDP (calpastatin) by 52%. Cimaterol-dependent myofibrillar protein accretion was likely mediated, at least in part, by a reduction in MPD. The change in MPD was associated with a reduction in muscle CDP activities. Cimaterol-dependent muscle hypertrophy therefore may involve changes in calcium-dependent proteolysis of myofibrillar proteins. The significance of the effects of cimaterol on calpastatin activity is not known.     

Dynamics in serum of the inflammatory markers serum amyloid A (SAA), haptoglobin,fibrinogen and alpha2-globulins during induced noninfectious arthritis in the horse

Despite the importance of noninfectious joint diseases in equine medicine, little is known about the acute phase response which may be elicited if the local inflammatory process of noninfectious arthritis is sufficiently strong, Therefore the aim of this study was to monitor the systemic inflammatory response during experimentally-induced noninfectious arthritis by studying the dynamics in serum of the acute phase proteins serum amyloid A (SAA), haptoglobin, fibrinogen and alpha2-globulins. Twenty-four Standardbred horses, age 3-7 years, found healthy on thorough clinical, radiological, haematological and serum biochemical examination, were injected aseptically into the right midcarpal joint with amphotericin B. Blood samples were drawn before induction of arthritis (0 h), and at 8, 16, 24, 36 and 48 h postinduction and then on Days 3, 4, 5 and 15 postinduction. All horses developed lameness with joint effusion and joint heat as well as increased respiratory rate, heart rate and body temperature. The lameness started to decline after 24-36 h and, in most animals, systemic signs disappeared on Day 2 postinjection. The concentration of the acute phase proteins increased following induction of arthritis. The SAA concentrations were higher than baseline concentrations from 16 h postinduction and were maximal at 36-48 h (227 times baseline concentration). The haptoglobin concentrations were higher than baseline concentrations from 24 h and were maximal at 48-96 h (1.14 times baseline concentration). The maximal concentrations of fibrinogen were seen between 36-72 h postinjection and increased on average 0.87 times from baseline concentrations. The fibrinogen concentrations were higher than baseline concentrations from 24 h postinjection. Alpha2-globulins concentrations showed a minor increase and increased 0.55 times from baseline concentrations. The markers had returned to baseline concentrations by Day 15. Our results demonstrate that amphotericin B-induced arthritis in a single joint gives rise to a systemic acute phase response measurable as increased concentrations in serum SAA, haptoglobin, fibrinogen and alpha2-globulins during the first 2 weeks of the condition and, thereby, that such an increase need not be indicative of infectious arthritis. Further research should be aimed at determining whether chronic noninfectious arthritis in the horse gives rise to increased acute phase protein concentrations in serum.     

Breed Differences in Natriuretic Peptides in Healthy Dogs

Background

Measurement of plasma concentration of natriuretic peptides (NPs) is suggested to be of value in diagnosis of cardiac disease in dogs, but many factors other than cardiac status may influence their concentrations. Dog breed potentially is 1 such factor.

Objective

To investigate breed variation in plasma concentrations of pro‐atrial natriuretic peptide 31‐67 (proANP 31‐67) and N‐terminal B‐type natriuretic peptide (NT‐proBNP) in healthy dogs.

Animals

535 healthy, privately owned dogs of 9 breeds were examined at 5 centers as part of the European Union (EU) LUPA project.

Methods

Absence of cardiovascular disease or other clinically relevant organ‐related or systemic disease was ensured by thorough clinical investigation. Plasma concentrations of proANP 31‐67 and NT‐proBNP were measured by commercially available ELISA assays.

Results

Overall significant breed differences were found in proANP 31‐67 (P < .0001) and NT‐proBNP (P < .0001) concentrations. Pair‐wise comparisons between breeds differed in approximately 50% of comparisons for proANP 31‐67 as well as NT‐proBNP concentrations, both when including all centers and within each center. Interquartile range was large for many breeds, especially for NT‐proBNP. Among included breeds, Labrador Retrievers and Newfoundlands had highest median NT‐proBNP concentrations with concentrations 3 times as high as those of Dachshunds. German Shepherds and Cavalier King Charles Spaniels had the highest median proANP 31‐67 concentrations, twice the median concentration in Doberman Pinschers.

Conclusions and Clinical Importance

Considerable interbreed variation in plasma NP concentrations was found in healthy dogs. Intrabreed variation was large in several breeds, especially for NT‐proBNP. Additional studies are needed to establish breed‐specific reference ranges.     

Resumption of ovarian activity in zebu cows (Bos Indicus) in the humid tropics: influence of body condition and levels of certain blood components related to nutrition

Summary This study investigated the relationship between resumption of ovarian activity and body condition in a herd of 20 zebu cows in the humid tropics. Blood chemistry profiles to monitor nutritional status were also evaluated. Plasma progesterone was used to determine ovarian activity. During the study, which lasted 18 weekspost partum, 7 of the animals resumed ovarian activity while 13 remained in the anoestrous stage. The beginning of the first luteal phase was registered on day 87±19 (range 60 to 106). The animals which resumed cyclicity were in significantly better body condition and had significantly higher mean body weight than anoestrous cows. In the group which resumed ovarian activity, calcium levels decreased significantly from 3 weeks before until the first rise of progesterone in the first normal cycle. The study was divided into 2 periods corresponding to weeks 0 to 8 (I) and 9 to 18 (II) based on the finding that until week 8 all animals were reproductively inactive. During period I there were no significant differences between the groups in blood concentrations of albumin, glucose, urea, cholesterol, calcium and phosphorus. During period II albumin was significantly higher and urea significantly lower in the cows resuming ovarian activity. The results suggest that cows able to maintain their body condition from calving through the earlypost-partum period will have shorter intervals to firstpost-partum oestrus than cows which have lost body weight. The lower urea and higher albumin levels in the cyclic animals probably reflected a better feed efficiency—the demands of lactation were compensated by an altered nitrogen metabolism.

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Reinicio De La Actividad Ovarica En Vacas Zebu (Bos Indicus) En El Tropico Humedo: Influencia De La Condicion Corporal Y De Los Niveles Plasmaticos De Algunos Compuestos Relacionados Con La Nutricion

Resumen Este estudio investigó la relación entre el reinicio de la actividad ovárica y la condición corporal en un rebaño de 20 vacas zebú en el trópico húmedo. Se realizaron también análisis de sangre para monitorizar el estado nutricional de los animales. Se utilizaron los niveles plasmáticos de progesterona para determinar actividad ovárica. Durante el estudio, que duró las primeras 18 semanas postparto, 7 animales reiniciaron la actividad ovárica mientras que los 13 restantes permanecieron en anoestro. El inicio de la primera fase luteínica tuvo lugar el día 87±19 postparto (rango 16–106). Los animales que reiniciaron la actividad ovárica tenían una condición corporal significativamente mejor y un peso significativamente más alto que los animales que se mantuvieron en anoestro. En el grupo de animales que reinició la actividad ovárica, la concentración plasmática de calcio disminuyó significativamente durante las tres últimas semanas antes del aumento en la concentración de progesterona correspondiente al primer ciclo ovárico. Debido a que hasta la octava semana después del parto todos los animales estuvieron en anoestro, el estudio se dividió en dos períodos: período I (semanas 1 a 8) y período II (semanas 9 a 18). Durante el período I no se encontraron diferencias significativas entre los dos grupos de animales en las concentraciones plasmáticas de albúmina, glucosa, urea, colesterol, calcio ni fósforo. Durante el período II la concentración de albúmina fue significativamente más alta en el grupo de animales que reiniciaron la actividad ovárica, mientras que la concetración de urea fue significativamente mayor en los animales que permanecieron en anoestro. Los resultados sugieren que las vacas que son capaces de mantener su condición corporal durante las primeras semanas postparto tienen intervalos parto-estro más cortos que las vacas que han perdido condición corporal. El hecho de que los animales que reiniciaron antes su actividad ovárica tuvieran una concentración plasmática de albúmina superior y una concentración de urea inferior que los que permanecieron en anoestro probablemente refleja una mayor eficiencia en la utilización del alimento en los animales que reiniciaron la actividad ovárica. Es decir, las demanadas energéticas de la lactación fueron compensadas mediante un cambio en el metabolismo del nitrógeno.

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Reprise De l'Activite Ovarienne Chez Des Femelles Zebus (Bos Indicus) Dans Les Pays Tropicaux Humides: Influence De l'Etat De Sante Et Des Teneurs De Certains Composants Sanguins Lies A l'Alimentation

Résumé Cette étude examina la relation centre la reprise de l'activité ovarienne et l'état de santé d'un groupe de 20 femelles zébus des pays tropicaux humides. Les profiles chimiques du sang furent aussi analysés pour contrôler l'état nutritionnel. La teneur en progestérone du plasma fut utilisée pour déterminer l'activité ovarienne. Pendant l'étude, qui dura 18 semaines après le vêlage, sept animaux reprirent une activité ovarienne alors que treize restèrent à un stade sans oestrus. Le début de la première phase lutéale fut enregistré au jour 87±19 (écart 60–106). Les animaux qui reprirent des cycles furent de façon significative en meilleure condition physique et eurent un poids moyen significativement superieur aux femelles sans oestrus. Dans le groupe qui reprit une activité ovarienne, les teneurs en calcium diminuèrent de façon significative trois semaines avant la première montée de progestérone du premier cycle normalisé. L'étude fut divisée en deux périodes correspondant aux semaines 0–8 (phase I) et 9–18 (phase II) se basant sur le fait que les animaux furent tous inactifs du point de vue reproductif jusqu'a la huitième semaine. Pendant la phase I, il n'y eut pas de différences significatives entre les groupes pour les concentrations sanguines en albumine, glucose, urée, cholestérol, calcium et phosphore. Pendant la phase II l'albumine fut de façon significative plus élevée et l'urée plus basse chez les femelles reprenant une activité ovarienne. Les résultats suggèrent que les femelles capables de maintenir leur condition physique pendant toute la période du vêlage auront un premier oestrus plus rapide que les femelles ayant perdu du poids. Les teneurs plus faibles en urée et plus fortes en albumine chez les animaux ayant un cycle reflètent probablement d'une meilleure efficacité dans la nutrition. Les demands en lactation furent compensées par l'altération due métabolisme azoté.

     

Leaching of Metals from Oxidising Sulphide Mine Tailings with and without Sewage Sludge Application

A 20-month column experiment investigated leaching of Al, Cu, Mn, Ni, Zn, Cd and Pb during sulphide oxidation in mine tailings with and without sewage sludge (SS) amendment. Leachate pH decreased gradually in all columns during the experiment, irrespective of treatment, due to sulphide oxidation. As the degree of sulphide oxidation, and thus the pH trajectory, differed between replicates (n?=?3), running data for each column used are reported separately and the relationships between sulphide oxidation, metal leaching and treatment in each column compared. Mean pH in the columns correlated negatively with total amounts of leached SO₄ ^2-. In the beginning of the experiment the leachate concentrations of Al, Cu, Zn, Ni and Pb were higher in SS-treated columns due to high initial concentrations of dissolved organic carbon. As leaching proceeded, however, the amounts of Al, Cu, Mn and Ni leached from the columns were closely related to the degree of sulphide oxidation in each column, i.e. to its mean pH. There were no statistically significant differences between treatments regarding the total amounts of metals leached and thus addition of sewage sludge to the tailings appeared to play a minor role for metal leaching patterns. Peak concentrations of Al and Cu in the leachate from untreated tailings and of Zn in the leachate from both untreated and SS-treated tailings at pH 4 exceeded national background values for groundwater.     

The Effects of Replacing Rhodes Grass (Chloris gayana) Hay with Ghaf (Prosopis cineraria) Pods on the Performance of Omani Native Sheep

A feeding trial using various levels of dry pods of ghaf (Prosopis cineraria) was carried out with 28 Omani native male sheep. Individual feed intake and body weight were determined for 50 days to allow assessment of the effects of the feeds on growth, feed intake, feed conversion and carcase measurements. The ripened ghaf pods contained 91% dry matter (DM), 13.5% crude protein (CP), 14.3% crude fibre (CF), 1.3% ether extract (EE) and 5.2% ash (on DM basis). Four levels of ghaf (0, 15%, 30% and 45%) were used with corresponding decreasing proportions of Rhodes grass (RGH) hay. Animals fed rations containing RGH as the sole source of roughage and no ghaf grew faster (135 g/day) and had better feed conversion than those fed various levels of ghaf. Sheep fed 15% ghaf gained reasonably well (90 g/day) and had carcase attributes similar to those fed no ghaf. Sheep fed 30% ghaf still gained weight but those fed 45% ghaf lost weight. Negative effects on growth appeared to occur after 6 weeks of feeding ghaf.     

An investigation on the presence of Chlamydiaceae in Swedish dogs

Background

Bacteria belonging to the family Chlamydiaceae cause a broad spectrum of diseases in a wide range of hosts, including man, other mammals, and birds. Upper respiratory and genital diseases are common clinical problems caused by Chlamydiaceae. Very little is known about chlamydial infections in dogs. Few clinical reports on natural disease in dogs describe mainly conjunctival and upper respiratory signs, and the role of Chlamydiaceae in genital disease is unclear. The present study aimed at studying the prevalence of Chlamydiaceae in healthy dogs and in dogs with genital or upper respiratory disease, including conjunctivitis.

Methods

A real-time polymerase chain reaction (PCR) for Chlamydiaceae was used to detect any chlamydial species within this family. Swab samples from the conjunctiva and the mucosal membranes of the oropharynx, rectum and genital tract were taken from 79 dogs: 27 clinically healthy dogs, 25 dogs with clinical signs from the genital tract and 28 dogs with conjunctivitis. There were 52 female and 27 male dogs. From 7 of the male dogs, additional semen samples were analysed.

Results

No Chlamydiaceae were detected from any dog.

Conclusions

Although the number of dogs that was included is limited, the results suggest that cases of Chlamydiaceae in dogs probably are related to infection from other species, and that dogs in general do not harbour Chlamydiaceae. Bacteria belonging to the family Chlamydiaceae do not seem to be of major importance for genital or ocular disease in Swedish dogs.