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51.
A parallel investigation to characterize host reactions involved in wound repair following abiotic injury and challenge with Armillaria ostoyae in three conifer species (Douglas‐fir, western hemlock and western redcedar) was conducted in the southern Interior of British Columbia. In this study, we characterize wound healing in roots following freezing injuries to the bark. Five weeks following wounding, all conifers developed lignified impervious tissue (IT) around killed tissue, and a necrophylactic periderm (NP) formed internally abutting IT, although IT was difficult to discern in western redcedar. Phellogen restoration in the secondary phloem of some western hemlock roots was retarded around large clusters of sclereids. Displacement of phloem fibre cells occurred in western redcedar but did not appear to delay NP formation. In roots exhibiting expansion of necrosis to the vascular cambium, callus tissue was evident at the margin of the wound. Novel host reactions in western redcedar involving induced rhytidome formation and the formation of traumatic phloem resin ducts are described.  相似文献   
52.
The incidence of low day 5 milk progesterone in dairy cows has been investigated and the efficacy of treating the problem assessed. The incidence of inadequate milk progesterone (empirically defined as <3ng/mL) in repeat breeder cows was 34% compared with 11.4% in first insemination cows. Treatment with an intravaginal progesterone device for 7 days starting from day 5 or 6 did not improve pregnancy rate. Treatment with 1500 iu human chorionic gonadotrophin (hCG) on day 5 gave an increase in pregnancy rate that was dependent on initial progesterone concentration and significant (P<0.05) in multiparous but not primiparous cows. While the incidence of inadequate day 5 progesterone was high in repeat breeder cows, it was responsive to hCG treatment, although only in multiparous and not primiparous animals.  相似文献   
53.
The circadian body (vaginal) temperature rhythm was measured in 36 dairy cows: Holstein–Friesian (HF, n = 12), Jersey (J, n = 12) and their crossbreed, Holstein–Friesian × Jersey (HF × J, n = 12) at six different periods (5-7 days in duration) during the year that could potentially be a seasonal and physiological stressor. These were a) early winter (late pregnancy), (b) early spring (early lactation), (c) late spring (before mating at mid-lactation), (d) early summer (after mating at mid-lactation), (e) late summer (late lactation, early pregnancy) and, (f) early autumn (drying-off at the end of lactation, mid-pregnancy). Live weight and body condition score was recorded on the first day of each measurement period. Live weight differed (P < 0.001) with breed with HF cows heaviest and J cows lightest (HF: 525 ± 51, HF × J: 456 ± 56, J: 401 ± 30 kg). HF cows tended (P = 0.099) to have a higher body condition than either J or HF × J cows although the overall change in body condition during the experiment was similar (P = 0.961) amongst breeds. The circadian body temperature rhythm differed markedly between each measurement period, being flatter and having a less prominent morning nadir and afternoon peak during early winter compared to spring and summer. The timing of peak body temperature was 4-5 h earlier in early autumn in HF and HF × J cows relative to J cows. There was no breed difference (P ≥ 0.162) in daily mean body temperature except for a tendency (P = 0.075) for mean body temperature to be moderately higher in J cows (38.5 °C) during late summer compared to HF and HF × J cows (38.4 °C), primarily due to an increase (P = 0.001) in daily minimum body temperature (38.0 vs. 37.8 °C). The daily range of oscillation (maximum–minimum) in the body temperature rhythm was highest during late summer, particularly in HF and HF × J cows. Minimum body temperature was also higher (P = 0.033) for J cows than HF and HF × J cows during early autumn (37.9 vs. 37.8 °C). In conclusion, season and physiological status of cattle had a profound effect on the circadian body temperature rhythm but there was little difference between the breeds of dairy cows studied.  相似文献   
54.
OBJECTIVE: To better characterise the bone and joint problems which can develop in Scottish Fold cats. DESIGN: Retrospective study of cases seen in five veterinary clinics and radiographic survey of cats in a cattery. RESULTS: Six Scottish Fold cats (four castrated males, two spayed females) aged between 5 months and 6 years were presented for signs of skeletal disease including lameness, reluctance to jump, a stiff stilted gait, short misshapen distal limbs, swelling of plantar tarsometatarsal regions and short thick inflexible tails. A further four cases (one male, three females, 15 months to 11 years) were identified by radiographic screening of a cattery. A diagnosis of osteochondrodysplasia was based on characteristic radiological findings including irregularity in the size and shape of tarsal, carpal, metatarsal and metacarpal bones, phalanges and caudal vertebrae, narrowed joint spaces, and progressive new bone formation around joints of distal limbs with diffuse osteopenia of adjacent bone. A plantar exostosis caudal to the calcaneus was present in advanced cases. In all nine cases where pedigree information was available, affected cats allegedly originated from the mating of a Scottish Fold to a cat with normal ears. The severity and time of onset of physical signs, and rate of progression and extent of radiographic abnormalities, varied from case to case. Limited histological observations suggested the underlying problem may be an osteochondrodysplasia, related to inadequate cartilage maturation. Clinical signs were ameliorated by administration of pentosan subcutaneously in two of three cats in which it was trailed, and one of these also benefited from an oral glycosaminoglycan preparation. CONCLUSIONS: Clinical and radiological findings were ascribed to defective maturation and function of cartilage, particularly in the distal limbs, ears and tail. As all Scottish Fold cats suffered from osteochondrodysplasia of some degree, the best solution would be to avoid using fold-eared cats for breeding and instead use Scottish shorthairs.  相似文献   
55.
56.
A 12.5-year-old dog was presented for severe periodontal disease and bilateral maxillary enlargement. Radiographs of the maxilla showedgeneralized root resorption, ankylosis, and rarefaction of bone with focal radiodense areas. Surgical tooth extraction of multiple maxillary teeth and bilateral incisional biopsies of the periodontal tissue and maxilla in the region of the maxillary fourth premolars were performed. Histopathologic examination showed features typical of fully differentiated periodontal ligament with abundant cementum/alveolar lining bone and sparce odontogenic epithelial cell rests. Histopathology in conjunction with radiographic and clinical signs suggested a diagnosis of bilateral periodontal ligament hamartoma. Examination 3-months postoperatively indicated uncomplicated healing of the extraction and biopsy sites with no resolution of the maxillary enlargement.  相似文献   
57.
The pelagic larval duration (PLD) period of fish can influence dispersal, recruitment, and population connectivity, thereby potentially informing best strategies for fisheries management. Computer models were used to simulate the dispersal of larvae of three species, representing a range of PLDs, from the Pacific island of Guam and neighboring islands for a 9‐year period (2004–2012) to gain insight into the best management strategies for these species. The species included two springtime spawners with shorter and longer PLDs, scribbled rabbitfish (Siganus spinus; 33 days) and yellowfin goatfish (Mulloidichthys flavolineatus; ~90 days maximum), and a fall spawner with a similarly long PLD, bluespine unicornfish (Naso unicornis; ~94 days maximum). An ocean circulation model coupled with a particle dispersal model provided simulated numbers of larvae settling at each island in relation to the island where they were spawned. Graph analysis was used to examine generational connections between islands. For S. spinus, self‐seeding was the dominant means of replenishment at Guam. Local management actions to maintain adequate spawning stock may be a primary control on long‐term sustainability for that fishery. In contrast, N. unicornis and M. flavolineatus populations at Guam were reliant on outside sources for 92%–98% of larval supply. For them, identifying and negotiating the preservation of upstream spawning potential in the Marshall Islands and Federated States of Micronesia will be needed. Guam played a relatively minor role in generational connectivity across the region. Shortest paths spanning the region often did not pass through Guam, or there were equally short paths through other islands.  相似文献   
58.
Pacific salmon and trout (Oncorhynchus spp., Salmonidae) of the Puget Sound region of Washington State, USA, have experienced recent and longer‐term (multidecadal) variability in abundance while supporting robust fisheries. As part of the post‐season salmon management process, population‐specific estimates of total adult abundance to Puget Sound (Strait of Juan de Fuca) for pink (O. gorbuscha), chum (O. keta), coho (O. kisutch), sockeye (O. nerka), and Chinook (O. tshawytscha) salmon and steelhead trout (O. mykiss) are calculated annually. We compiled annual estimates of body mass, abundance and survival of hatchery‐ and naturally produced salmon from 1970 to 2015 to compare spatial and temporal patterns across species. Average weights of adult salmon and steelhead returning to Puget Sound, with the exception of coho salmon, have decreased since the 1970s. Temporal trends in abundance, survival and productivity varied by species and origin (hatchery vs. naturally produced). Generally, abundance and survival rates of natural‐origin species decreased whereas those of hatchery‐produced species did not, which is in contrast with other studies' general conclusions of decreasing survival among Puget Sound salmonids. Species diversity has decreased in recent years, with salmonids that rely on a short freshwater rearing phase in the natural environment (hatchery‐produced fish and naturally produced pink and chum) representing >90% of total returns in most years. This new information reveals patterns of body size, abundance, survival and productivity across species, life history and rearing type over the past 45 years and, in doing so, demonstrates the strength in multidecadal, multifactor time series to critically evaluate salmonid species.  相似文献   
59.
Six ruminally cannulated steers (average BW = 791 ± 71 kg) were used in a replicated 3 × 3 Latin square experiment to determine the effects of roughage type on rumination, fiber mat characteristics, and rumen fermentation variables. Three roughages were included at 7% (DM basis) in a steam flaked corn-based diet: cotton burrs (CB), wheat silage (WS), or corn stalks (CS). Steers were fitted with a sensory collar to record rumination behaviors in 2-h intervals at the beginning of the experiment. Each 30-d period consisted of 7 d of recovery, 14 d of diet adaptation, 7 d of rumination data collection (daily and bi-hourly average rumination), 1 d of rumen fluid collection, and 1 d of rumen evacuations. In situ degradation of individual roughages was determined for 4 d after period 3 evacuations. During rumen evacuations, ruminal contents were removed; the rumen fiber mat (RF) was separated from the liquid portion with a 2-mm sieve, weighed, and a subsample was dried. Data were analyzed using the MIXED procedure of SAS with steer as the experimental unit and roughage (CB, WS, and CS) as the main effect. Dry matter intake (DMI) was not different for CB and WS (P = 0.25) and greatest for steers consuming CS diet (P ≤ 0.01). Roughage type did not influence the weight of the RF dry matter (%; DM; P = 0.92), RF weight (P = 0.69), or RF:DMI ratio (P = 0.29). Daily rumination (min/d) did not differ among roughages (P = 0.40), but min of rumination/kg of DMI was greatest for CS (18.0 min), min/kg of NDF was greatest for WS (89.8 min; P = 0.02), and min/kg of peNDF was greatest for CS (132.4 min; P ≤ 0.01). Wheat silage had the greatest percentage of soluble and degradable DM. Rumen fiber mat did not differ for roughages, although rumination min/kg of DMI and peNDF was greatest for steers consuming CS and WS. In situ degradation determined that CB-R and CS-R had the greatest percentage of ruminal undegraded DM. Based on the objective of the experiment, roughage type did not influence daily rumination or fiber mat characteristics.  相似文献   
60.
Summary This records some gut and blood parasites of sheep, cattle, buffaloes and camels in the Aswan Governorate of Egypt.  相似文献   
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