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1.
Estuarine habitats provide rearing opportunities for the juvenile life stage of anadromous fishes. Because survival is positively correlated with juvenile performance, these estuarine habitats play an important role in population abundance and productivity. To provide information for the recovery of several depressed stocks of Chinook salmon in the Columbia River Basin, we sought to identify the factors that explain variability in performance. Using otolith‐derived estimates of juvenile somatic growth rate as an index of recent performance, we observed a negative nonlinear relationship between growth rate and day of year, and a decreasing and increasing trend of growth rate over the 8 years of this study and distance from the river mouth respectively. Using a generalised linear modelling approach, we found that variability in juvenile somatic growth rate was best explained by where and when individuals were collected, their body size, contaminant loads, stock of origin, and whether a fish was hatchery produced or unmarked. Lastly, we argue that a considerable improvement to the growth rate of juveniles in estuarine habitats is physiologically possible. The results of this 8‐year study provide a baseline of the performance of juvenile Chinook salmon to evaluate habitat restoration programs and to compare against future anthropogenic conditions.  相似文献   
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Diagnosis of mastitis for therapy decisions.   总被引:2,自引:0,他引:2  
Identifying specific groups of mastitis pathogens by their growth on selective agars can help identify the pathogens that are present in mastitic milk samples. This article addresses issues that are essential in making good use of diagnostic procedures to improve udder health on dairies.  相似文献   
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Using a cross-sectional survey, we determined the prevalence and risk factors associated with bovine brucellosis in herds under extensive production system in southwestern Nigeria. Antibodies to Brucella species in serum samples were tested using the Rose Bengal test (RBT) and competitive enzyme-linked immunosorbent assay (cELISA); for milk, the milk ring test (MRT) and indirect-ELISA (i-ELISA) were used. Questionnaire was administered to cattle herdsmen to determine factors predisposing the animals to bovine brucellosis. Data were analyzed using STATA 12. From 513 serum and 635 milk samples tested among 120 herds, overall animal-level prevalence of 10.1% (95% CI 7.5–12.7%) and 20.2% (95% CI 17.1–23.3%) were recorded by RBT and MRT, respectively; while 9.4% (95% CI 6.9–11.9%) and 17.8% (95% CI 14.8–20.8%) were obtained using cELISA and i-ELISA, respectively. In all, from the 120 herds tested, 29.2% and 43.3% were positive by RBT and MRT, respectively. Multivariable logistic regression revealed that herd location (OR?=?8.12, 95% CI 1.68–38.90) and improper disposal of placenta/fetus (OR?=?17.33, 95% CI 4.81–62.33) were predictors for a seropositive herd using RBT; while herd location (OR?=?5.13, 95% CI 1.27–20.28), large herd size (OR?=?2.62, 95% CI 1.15–5.85), and occurrence of abortion for a year or more (OR?=?4.62, 95% CI 1.53–13.71) were predictors of seropositivity to antibodies to Brucella spp. using MRT. We found high prevalence of brucellosis in cattle herds under extensive management system in southwestern Nigeria. Urgent and coordinated control strategies are required to mitigate this problem.

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Although pork producers typically aim to optimize growth rates, occasionally it is necessary to slow growth, such as when harvest facility capacity is limited. In finishing pigs, numerous dietary strategies can be used to slow growth so pigs are at optimal slaughter body weights when harvest facility capacity and/or access is restored. However, the impact of these diets on pork carcass quality is largely unknown. Thus, this study aimed to evaluate the efficacy of dietary strategies to slow growth in late finishing pigs and evaluate their effects on carcass composition and pork quality. Mixed-sex pigs (n = 897; 125 ± 2 kg BW) were randomly allotted across 48 pens and assigned to 1 of 6 dietary treatments (n = 8 pens/treatment): (1) Control diet representative of a typical finisher diet (CON); (2) diet containing 3% calcium chloride (CaCl2); (3) diet containing 97% corn and no soybean meal (Corn); (4) diet deficient in isoleucine (LowIle); (5) diet containing 15% neutral detergent fiber (NDF) from soybean hulls (15% NDF); and (6) diet containing 20% NDF from soybean hulls (20% NDF). Over 42 d, pen body weights and feed disappearance were collected. Pigs were harvested in 3 groups (14, 28, and 42 d on feed) and carcass data collected. From the harvest group, 1 loin was collected from 120 randomly selected carcasses (20 loins/treatment) to evaluate pork quality traits. Overall, ADG was reduced in CaCl2, Corn, and 20% NDF pigs compared with CON pigs (P < 0.001). However, ADFI was only reduced in CaCl2 and 20% NDF pigs compared with CON (P < 0.001). Feed efficiency was reduced in CaCl2 and Corn pigs compared with CON (P < 0.001). Hot carcass weights were reduced in CaCl2 pigs at all harvest dates (P < 0.001) and were reduced in Corn and 20% NDF pigs at days 28 and 42 compared with CON pigs (P < 0.001). In general, CaCl2 and 20% NDF diets resulted in leaner carcasses, whereas the Corn diet increased backfat by 42 d on test (P < 0.05). Loin pH was reduced and star probe increased in CaCl2 pigs compared with CON pigs (P < 0.05); no treatments differed from CON pigs regarding drip loss, cook loss, color, firmness, or marbling (P ≥ 0.117). Overall, these data indicate that several dietary strategies can slow finishing pig growth without evidence of behavioral vices. However, changes to carcass composition and quality were also observed, indicating quality should be taken into consideration when choosing diets to slow growth.  相似文献   
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European researchers from both the natural and social sciences show growing interest in studying interactions between society and wildlife. A wealth of theoretical frameworks, concepts, and methods are used, but an integration of perspectives is lacking. This research note summarizes results from two workshops that included 63 delegates from 25 European countries, as well as a follow-up survey of 41 respondents. Two main theoretical approaches to the study of human–wildlife interactions were identified. One approach focuses on the collective societal level relying on theories of governance, social representation, deliberative procedures, and commons theory. The other approach targets individuals or groups, and is based on theories such as the cognitive hierarchy, theory of reasoned action, and theory of planned behavior. Interdisciplinary collaboration is needed to identify the best options for wildlife conservation and management in a more politically integrated Europe.  相似文献   
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CASE DESCRIPTION: A 6-month-old male Bactrian camel was examined because of a 3-week history of lameness of the left hind limb. CLINICAL FINDINGS: Lameness was initially detected in the left hind limb but resolved and was detected in the right hind limb during treatment. Lameness increased during periods of rapid growth. Radiography revealed multiple small opacities of the medullary cavity of several long bones throughout treatment. Core bone biopsies of lesions in the tibiae revealed lamellar bone with areas of loose connective tissue, osteoblasts in the medullary cavity, and periosteal new bone formation, all which were consistent with panosteitis. TREATMENT AND OUTCOME: Palliative treatment was attempted with epidural and transdermal administration of analgesics. Flunixin meglumine was administered PO, which coincided with an abrupt increase in serum creatinine concentration. Performance of multiple diagnostic bone biopsies led to remission of clinical signs of pain. CLINICAL RELEVANCE: Panosteitis should be a differential diagnosis for shifting limb lameness in young camels. Bone biopsies can be useful for diagnosis of panosteitis and possible relief of pain associated with the disease. Bactrian camels may be susceptible to the renal toxicity of flunixin meglumine, especially when dehydrated.  相似文献   
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OBJECTIVE: To determine historical, physical, and microbiologic findings in horses with limb cellulitis and identify factors associated with short- and long-term outcome. DESIGN: Retrospective case series. ANIMALS: 44 horses with limb cellulitis. PROCEDURES: Information obtained from medical records included use, history, affected limb, diagnostic procedures, treatment, and short-term outcome. Long-term follow-up information was obtained by means of a telephone survey. RESULTS: Twenty-four horses had primary cellulitis, and 18 of the 24 (75%) had a hind limb affected. Results of microbiologic culture were positive for all 20 horses with primary cellulitis from which specimens were obtained, with coagulase-positive Staphylococcus spp recovered from 12 of the 20. Short-term survival rate was 67% (16/24) for horses with primary cellulitis; 7 of the 9 horses available for long-term follow-up were being used for their intended use, and 4 had had a recurrence. Results of microbiologic culture were positive for 13 of the 16 (81%) horses with secondary cellulitis from which specimens were obtained. Short-term survival rate for horses with secondary cellulitis was 90% (18/20). Eleven of the 17 horses available for long-term follow-up were being used for their intended use; 2 had had a recurrence. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that cellulitis can be a life-threatening condition in horses. Horses that were febrile at admission or that developed laminitis were significantly less likely to survive. The prognosis for return to function was guarded, and recurrence was a potential concern.  相似文献   
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