Contents of Volume 8

Volume Contents

Contents of Volume 8     

Handling time and predation behaviour by the crab, Cancer pagurus, preying on cultured scallop, Pecten maximus

We investigated handling time, persistence time and shell‐breaking techniques by crab, Cancer pagurus (L.) (13–15 cm carapace width), offered cultured scallops, Pecten maximus(L.), within the recommended release size for bottom culture. Three shell height groups were used: 50–55, 60–65 and 70–75 mm. The results showed that the crabs managed to open scallops from all the three size groups. The median handling time in the 50–55 mm group (788 s) was significantly different from the median handling time of the 60–65 mm (2482 s) and 70–75 mm (2980 s) groups. The median persistence time increased significantly with each scallop size, from 89 s in the 50–55 mm group to 97 s in the 60–65 mm and 125 s in the 70–75 mm group. We observed a change in the shell‐breaking techniques from a dominance of smashed scallops in the 50–55 mm group to more punched and chipped scallops in the 60–65 and 70–75 mm groups. The shift in predation behaviour when crabs were offered 50–55 mm scallops compared with the larger groups is discussed in relation to strategies in the release of scallops to seabed cultures.     

Osseous lesions resembling vaccine-site sar comas in two cats

Extract

Lytic lesions with microscopic features similar to those of vaccine-site sarcomas were diagnosed in the distal femur of two young neutered male cats, one a 20-month-old Birman and the other an 18-month-old domestic short-hair (DSH). Radiographically, there was extensive destruction of trabecular and cortical bone in the metaphysis and/or epiphysis of the distal femur. The DSH cat also had angular deformity of the distal femur due to asymmetrical involvement of the physis. Histologically, the lesions in both cats consisted of dense, interwoven bundles of fibrous connective tissue, amongst which there were variable numbers of plump malignant mesenchymal cells, often with very large, hyperchromatic nuclei and irregularly shaped nucleoli. Several focal aggregates of small lymphocytes were present in both tumours. Although neither cat had apparently been vaccinated in the hindlimb it is possible that the tumours had been triggered by injection of some other irritant material.     

Bull Selection across Age Classes and Variable Female Reproductive Rates in an Open Nucleus Breeding Scheme for Dairy Cattle

Different bull selection strategies and female reproductive rates were simulated under various selection intensities and mating strategies in a nucleus with testing capacity of 80 cows. In all schemes, donor cows were selected after first lactation and bulls were progeny tested. In some schemes, non-progeny tested nucleus bulls could be selected. The nucleus was open on the male side but closed on the female side after nucleus born cows were available. Pedigrees of animals born outside the nucleus were sampled from the Finnish Ayrshire population. Female reproduction rate was either constant or variable. Schemes were compared according to genetic response, and risks measured by rate of inbreeding and coefficient of variation in genetic response between simulation years 5 and 20. Inclusion of one- or three-year-old bulls increased genetic response by 9% and rate of inbreeding up to 81%. Variation in female reproductive rate reduced genetic response by at most 8%. Increase in risks was averted by limiting the number of female full-sibs. Schemes with low selection intensity and factorial mating provided the best results.     

Learning from the past to predict the future: using archaeological findings and GPS data to quantify reindeer sensitivity to anthropogenic disturbance in Norway

Norwegian wild reindeer Rangifer tarandus tarandus are divided into 23 virtually isolated populations, primarily due to the abandonment of traditional migration and movement corridors caused by the development of infrastructures. By conducting a nation-wide, interdisciplinary pre-post study on a temporal scale spanning centuries, we modelled current reindeer movements with respect to archaeological findings to quantify long-term changes in area use related to anthropogenic disturbance. The location of 3,113 pitfall traps and hunting blinds, built 600–2000 years ago and used until 350–400 years ago, testified the location of traditional movement corridors. Current movement routes were delineated using Brownian Bridge Movement Models based on 147 reindeer GPS-monitored during 10 years. Using Path Analysis we quantified direct, indirect and total effects of different infrastructures within multiple scales (1, 5, and 10 km-radius buffers) on the current probability of use of ancient movement corridors. Tourist cabins and roads had the strongest long-term direct effects at most scales: 1 tourist cabin and 1 km road within a 1 km-radius buffer would lead, respectively, to complete area abandonment, and to a 46 % decrease in the probability of use. Power lines and private cabins had significant indirect effects on area use through their effect on roads, while hiking trails and, in particular, hydroelectric dams had highly variable effects, not significant at a nation-wide scale. Finally, we provide a flexible tool to estimate the potential long-term direct and cumulative effects of different types of infrastructures at the desired spatial scale to be used for the development of future sustainable land management plans.     

Expression of Genes in the Canine Pre‐implantation Uterus and Embryo: Implications for an Active Role of the Embryo Before and During Invasion

The aim of the present study was to assess genes expressed in maternal uterine tissue and pre‐implantation embryos which are presumably involved in maternal recognition and establishment of canine pregnancy. For this purpose, 10 pregnant bitches were ovariohysterectomized between days 10 and 12 after mating. Four non‐pregnant bitches served as controls. Early pregnancy was verified by flushing the uterine horns with PBS solution. The collected embryos (n = 60) were stored deep‐frozen (?80°C). Uterine tissue was excised, snaps frozen in liquid nitrogen and homogenized using TRI Reagent. All embryos from one litter were thawed together and also homogenized in TRI Reagent. RT‐PCR was performed to prove mRNA expression of progesterone receptor, key enzymes of the prostaglandin synthesis pathway, selected growth factors, cytokines, immune cell receptors, major histocompatibility complex (MHC) and matrix‐metalloproteinases (MMP). Only pregnant uteri revealed the presence of mRNA for interferon (IFN)‐γ, IL‐4 and CD‐8, which resembles the milieu in humans and other mammalians. Similarly, in day 10 embryos, mRNA for transforming growth factor‐β, insulin‐like growth factor‐1,‐2, hepatocyte growth factor, leukaemia inhibitor factor, tumour necrosis factor‐α, interleukin‐1β,‐6,‐8, cyclooxygenase‐2, CD4⁺ cells, and MMP‐2 and ‐9 were detected, but not MHC‐I or ‐II. We therefore suppose that the canine embryo, like its human counterpart, actively initiates measures to prevent attacks from the maternal immune system to prepare its own adhesion, nidation, growth and further development.     

Wintersweet (Chimonanthus praecox) toxicity in four goats

CASE HISTORY: A one-year-old female goat presented with acute onset of recumbency, seizures and vocalisation approximately 5 hours after being given access to branch trimmings from a neighbour's garden. The plant from which the pruned branches came was subsequently identified as wintersweet (Chimonanthus praecox). Three other goats kept in the same paddock displayed similar clinical signs over a period of 4 hours following the initial presentation.

CLINICAL FINDINGS: All four goats were ataxic, displayed tetanic seizures and were in lateral recumbency; they had dilated pupils and were hyperaesthetic, with elevated heart and respiratory rates. After symptomatic treatment, including sedation with diazepam, one of the three goats continued to deteriorate and was subjected to euthanasia. The remaining three goats recovered over 1–14 days with nursing care and physiotherapy.

DIAGNOSIS: Toxicity due to ingestion of wintersweet, which contains the alkaloid calycanthine.

CLINICAL RELEVANCE: Calycanthine is a central nervous system toxin, causing convulsions. Wintersweet shrubs are present in many New Zealand gardens. Practitioners should be aware that the seeds and flowers, and possibly the leaves, of this plant are highly toxic with signs of toxicity including ataxia, hyperaesthesia and seizures.     

Efficiency of uterine fluid cytology in the diagnosis of subclinical endometritis in the water buffalo (Bubalus bubalis)

This study compared endometrial cytology vis‐a‐vis uterine fluid cytology for assessment of uterine health in clinically normal and subclinical endometritis (SE)‐affected buffaloes. Uterine fluid samples and endometrial samples were collected from the buffaloes (n = 38) at oestrus using blue sheath and cytobrush, respectively. The smears were stained with Field stain for 3 minutes, and a minimum of 400 cells were counted in each smear for determination of the percentage of polymorphonuclear (PMN) leucocyte. The incidence of subclinical endometritis, based on the cytobrush cytology, was 23.08%. The correlation between cytobrush cytology with uterine fluid cytology was positive and significant (r = .37; p = .02). The ratio of PMN leucocyte in cytobrush cytology to uterine fluid cytology was 1:2.4. ROC analysis revealed that the threshold value of 6.16% PMN leucocyte in uterine fluid cytology showed a diagnostic sensitivity and specificity of 100% in differentiating normal from SE‐affected buffaloes. In conclusion, collection of uterine fluid was easier compared to collection of endometrial samples using cytobrush and the percentage of PMN leucocyte in uterine fluid cytology can be used as a tool for diagnosis of subclinical endometritis in buffaloes.     

Forecasting the genetic influences of red drum stock enhancement in South Carolina

The South Carolina Department of Natural Resources (SCDNR) began stocking red drum, Sciaenops ocellatus (Linnaeus), in 1989 to augment the abundance of juveniles available for recreational harvest in South Carolina estuaries. While stock enhancement can help supplement wild populations under high fishing pressure, releasing hatchery‐raised fish into the wild also presents the risk of decreased genetic diversity. An individual‐based model (IBM) was developed to forecast the genetic influences of stocking on the wild spawning population to inform responsible stocking strategies. Model results indicated the SCDNR red drum stock enhancement programme should maintain mean contributions of stocked fish no greater than 30% per year class over a 45‐year stocking period, coupled with at least 10 effective breeders in the hatchery replaced annually, to maintain current levels of genetic diversity estimated in the wild population. The IBM is a useful tool for hatchery managers to guide responsible stock enhancement.