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81.
Loreen Brehaut B.Sc. R.H. Jones B.Med.Sc. M.B. Ch.B. D.C.P. P.J. McEwan M.Sc. J.A.R. Miles M.A. M.D. F.R.A.C.P. P.R.S.N.Z. 《New Zealand veterinary journal》2013,61(5):82-86
Extract In Dunedin, feline respiratory infections with a high morbidity, but a low mortality except in very young animals, commonly occur in epizootics and appear to be enzootic between these outbreaks. The affected animals develop a serous ocular discharge which later becomes mucoid, and a mucoid nasal discharge associated with sneezing especially after handling. While these signs of infection are present, the animals are anorexic and listless. The disease may last for two weeks or more and sometimes affected cats develop a chronic snuffle lasting for months despite treatment. The disease is usually referred to as “snuffles”, although it is probably identical with the syndrome called “rhinotracheitis”. In the summer time, it commonly occurs in boarding establishments where large numbers of pets collected from a wide area are left by summer vacationers. In breeding catteries, infections occur most often in the spring and especially at the time of the first warm weather. Young kittens about 5 to 10 days old are usually affected but kittens which escape infection at this stage not infrequently develop symptoms at about 6 weeks of age. 相似文献
82.
N.A. Philip M.B. Ch.B. 《New Zealand veterinary journal》2013,61(1-2):6-8
Extract Thanks to its being a notifiable disease, leptospirosis has been well documented in New Zealand for many years. In his Radio-Doctor series recently, Dr H. B. Turbott stated that the incidence of notification of this disease has doubled over each 5-year interval since the 1950s. A glance at the list of notifications published each month reveals that the greatest number comes from the dairying districts of the country, focal upon the Hamilton Health District. Most occupational diseases in the dairy industry have been eliminated or prevented, nowadays, with leptospirosis remaining the bogyman of people working with milking cattle. 相似文献
83.
C.H.G. Irvine B.V.Sc. N.G. Prentice M.B. Ch.B. M.R.A.C.P. 《New Zealand veterinary journal》2013,61(4):86-88
Extract In conjunction with a trial to determine the effect of nematode infestation upon the liveweight gain and wool production of young sheep (Brunsdon, unpublished), information was sought on the seasonal succession and availability on pasture of infective larvae of the principal trichostrongyle genera parasitic in sheep. Data were collected in the form of nematode populations found at postmortem examination of Romney lambs, previously maintained worm-free, which were exposed to risk of parasitism in the field. A series of these lambs ran with the flock in the above-mentioned trial and served as indicators of the abundance of infective larvae on the pasture. 相似文献
84.
R De Roover JMN Feugang PEJ Bols G Genicot Ch Hanzen 《Reproduction in domestic animals》2008,43(2):239-245
The aim of this retrospective study was to compare the number of follicles, cumulus oocyte complexes (COCs) and cultured In Vitro Produced (IVP) embryos obtained from 1396 non‐stimulated Ovum Pick‐up (OPU) sessions on 81 donor animals in a twice weekly OPU scheme. Results were obtained from 640 sessions following FSH‐LH superstimulation, on 112 donors subjected to OPU once every 2 weeks. The stimulation protocol started with the insertion of an ear implant containing 3 mg norgestomet (Crestar, Intervet, Belgium) 8 days before puncture (day ?8). The dominant follicle was ablated by ultrasound‐guided follicle puncture on day ?6. On day ?3 and day ?2, cows were injected with FSH (Ovagen, ICP) twice daily (8 am to 8 pm ), i.e. a total dose of 160 μg FSH and 40 μg LG per donor per stimulation cycle. Animals were punctured 48 h after the last FSH injection (day 0). Progesterone implants were removed the next day. Stimulated donor cows were treated with this protocol at 14‐day intervals. Follicles were visualized with a Dynamic Imaging ultrasound scanner, equipped with a 6.5 MHz sectorial probe. Follicles were punctured with 55 cm long, 18 gauge needles at an aspiration pressure corresponding to a flow rate of 15 ml/min. Cumulus oocyte complexes were recovered and processed in a routine IVF set‐up. Results demonstrate that, expressed per session, FSH stimulation prior to OPU increases production efficiency with significantly more follicles punctured and oocytes retrieved. However, when overall results during comparable 2‐week periods are considered (four non‐stimulated sessions vs one stimulated), more follicles are punctured and more oocytes are retrieved using the non‐stimulated protocol. No significant differences in the number of cultured embryos could be detected, indicating that FSH/LH stimulation prior to OPU might have a positive effect on in vitro oocyte developmental competence as more embryos are cultured with less, presumably better‐quality, oocytes. 相似文献
85.
Alejandra M. Toro Ospina Amanda Marchi Maiorano Rogrio A. Curi Guilherme L. Pereira Maria Eugenia Zerlotti‐Mercadante Joslaine Noely dos Santos Gonalves Cyrillo Rusbel R. Aspilcueta‐Borquis Josineudson A. II de V. Silva 《Reproduction in domestic animals》2019,54(12):1524-1531
Linkage disequilibrium (LD) plays an important role in genomic selection and mapping of quantitative trait loci (QTL). This study investigated the pattern of LD and effective population size (Ne) in Gir cattle selected for yearling weight. For this purpose, 173 animals with imputed genotypes (from 18 animals genotyped with the Illumina BovineHD BeadChip and 155 animals genotyped with the Bovine LDv4 panel) were analysed. The LD was evaluated at distances of 25–50 kb, 50–100 kb, 100–500 kb and 0.5–1 Mb. The Ne was estimated based on 5 past generations. The r2 values (a measure of LD) were, respectively, .35, .29, .18 and .032 for the distances evaluated. The LD estimates decreased with increasing distance of SNP pairs and LD persisted up to a distance of 100 kb (r2 = .29). The Ne was greater in generations 4 and 5 (24 and 30 animals, respectively) and declined drastically after the last generation (12 animals). The results showed high levels of LD and low Ne, which were probably due to the loss of genetic variability as a consequence of the structure of the Gir population studied. 相似文献
86.
87.
Inga Mewis und Ch. Ulrichs 《Anzeiger für Sch?dlingskunde》1999,72(5):113-121
The present study examined the morphological and physiological effects of amorphous diatomaceous earth against the stored
product pestsS. granarius, T. molitor andT. confusum. Diatomaceous earth, namely Fossil Shield? and Dryacide? increased the mortality rate of this insects. After contact with Fossil Shield? the individuals ofS. granarius had significant lost of weight and reduced their water content respectively. This showed that silica dusts break the water
barrier of the cuticle. However, it increases the transpiration rate of water across the cuticle and the insect died past
several times through dehydration. As well, an addition of food affected the effectiveness of dusts against insects. A lot
of stored product beetles will be able to produce metabolic water of feed substrates. This ability protects and weaves contrary
to the loss of water. Diatomaceous earth’s can be effective primarily through the sorptive properties of the hygroscopic particles.
One day after dust treatment a significant weight loss ofT. molitor pupae was recorded. The exposure to the silica dust Fossil Shield? caused partly an incomplete metamorphosis and death of the individuals. Pupae dipped in Fossil Shield? or abrasive aluminium dust and rolled for further five minutes, reduced not significant higher their weight as unrolled exuvial
stages. The morphological analyses of treated insects under the Scanning Electron Microscope showed, that the dust covered
the hole integument. Partly, the silica particles sunk into the cuticle. After application of Fossil Shield? at the cuticle of adults,T. molitor, did not show any wax layer. Also it could not be found once blocked by stigma of the mealworm. The dust particles accumulated
around the respiration openings and they partly overgrew.
相似文献
88.
Elva Mayra Toledo‐Cuevas Francisco J Moyano López Dariel Tovar Ramírez Carlos A Strüssmann Carlos Alfonso Álvarez‐González Carlos Cristian Martínez‐Chávez Carlos A Martínez‐Palacios 《Aquaculture Research》2011,42(6):776-786
The early development of the digestive biochemistry of three cultured Atherinopsids (two Odontesthes species and Chirostoma estor) was investigated. Relatively high lipolytic and high alkaline proteolytic activities were found in all species. In addition, gene expression of lipase and trypsin during the early development of C. estor not only indicates an early onset of the lipase activity but also demonstrates a major importance of protein digestion in this species. However, despite all of them share similar habitats, differences in their digestive activities were evident. The rise in the activities of brush border membrane enzymes correlated with the decrease in cytosolic activities, used as indicator of maturation of the digestive tract, was detected in both species of Odontesthes at 9 weeks after hatching. In contrast, no similar signs were measured in C. estor, this being in agreement to the long weaning period (nearly 5 months) reported for this species. 相似文献
89.
Is it possible to differentiate between environmental and fishery effects on abundance‐biomass variation? A case study of blackspot seabream (Pagellus bogaraveo) in the Strait of Gibraltar
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Juan Carlos Gutiérrez‐Estrada Juan Gil‐Herrera Inmaculada Pulido‐Calvo Ivone Alejandra Czerwinski 《Fisheries Oceanography》2017,26(4):455-475
We assessed the potential for simulation and modelling of the blackspot seabream (Pagellus bogaraveo) population in the Strait of Gibraltar to discriminate the environmental effects of fishery impacts. A discrete biomass–abundance dynamic model was implemented to obtain a simulated monthly time series of blackspot seabream biomass. On this simulated time series, autoregressive integrated moving average (ARIMA) models were fitted. The best ARIMA fit provided a significant correlation of 0.76 and persistence index higher than 0.85. The proportion of variance non‐explained by the ARIMA models was correlated with a time series of sea surface temperature (SST) and North Atlantic Oscillation (NAO). The analysis of global, annual and winter correlation between the proportion of variance not explained by the ARIMA models and environmental variables showed that significant associations were not detected over the full time series. Our analysis therefore suggests that overexploitation is the main factor responsible for the commercial depletion of blackspot seabream in the Strait of Gibraltar. 相似文献
90.
Juveniles of the Caribbean scallops Argopecten nucleus and Nodipecten nodosus were suspended in pearl nets at densities of 25%, 30% and 50% coverage of the bottom of the net (BC) during days. Additionally, adults of A. nucleus (>35 mm) were placed in lantern nets at densities of 40%, 50% and 65% BC during days. Stocking density affected the growth of animals, with higher growth rates obtained at the lower densities. Although the survival of the two scallops was not influenced at the densities studied, the 15-day net changes, and culture in water of <28 °C produced better survival of A. nucleus and N. nodosus respectively. Predators of the families Cymatiidae, Grapsidae, Portunidae, Majidae and Xanthidae were found in the culture nets of juvenile A. nucleus , but during the adult phase they were absent. Predators exhibited a dense-independent behaviour in relation to scallops. There was not any association between predator frequency and survival of A. nucleus . 相似文献