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1.
A supplementary feed containing 30% coffee pulp was evaluated for use in the culture of Tilapia aurea in El Salvador, Central America. A comparison of the coffee pulp feed with a feed containing all of the same ingredients except coffee pulp was made with T. aurea raised in 1.0-m3 cages suspended in a fertilized earthen pond. Survival was high in all treatments and there was no significant difference in average weight gain between groups of fish receiving the two experimental feeds. Production trials were conducted in 100-m2 fish pens and in 0.05-ha earthen ponds. Pen-raised fish receiving coffee pulp feed grew faster throughout the experiment, and total production was approximately twice that in control treatments. Highest production in pens was 1.25 kg/m2 per year. Results of production pond trials using T. aurea at 9 000/ha and stocked with the piscivorous Cichlasoma managuense yielded an estimated 3 392 kg/ha per year in fed treatments and 2 049 kg/ha per year in controls. Low feed conversion (1.92) and low feed cost resulted in an increase in net annual earnings of $251.00/ha.  相似文献   
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Three types of raised perforated floor were compared with floor-level concrete which had perforated flooring at the rear. Piglets on raised perforated floors grew faster (P less than 0.05) to 21 days than pigs on mainly solid floors (205 g/day and 198 g/day, respectively). The mortality in the first 21 days of all pigs born did not differ between raised (18.4 per cent) and mainly solid floors (18.7 per cent) and there were no effects of individual floor types on overall survival or on deaths due to crushing. The incidence of diarrhoea was not significantly less on raised than on solid floors (27 per cent and 34 per cent of litters, respectively) but antibiotic treatment time was shortened (0.9 days and 1.2 days, P less than 0.05). The incidence of splayleg was highest on fibreglass slats. Concrete floors caused most knee abrasions but the incidence of arthritis was unaffected. Approximately twice as many sows on mainly solid floors went off their feed or had a high rectal temperature compared with sows on raised perforated floors. No differences were observed between narrow or A-frame farrowing crates.  相似文献   
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The objectives of this work were to determine the site of persistence of lumpy skin disease virus (LSDV) in bulls shedding the virus in semen for a period longer than 28 days, to determine if the virus is present in all fractions of semen and to study lesions that developed in the genital tract. Six serologically negative postpubertal bulls were experimentally infected with a virulent field isolate of LSDV. The polymerase chain reaction (PCR) was performed on sheath washes, vesicular fluid, supernatant and cell‐rich fractions of semen from day 10 to day 26 postinfection (p.i.). Bulls that were positive by PCR on the whole semen sample collected on day 28 p.i. were slaughtered and tissue samples from their genital tracts submitted for histopathological evaluation, immunoperoxidase staining, virus isolation and PCR. Two of the bulls developed severe lumpy skin disease (LSD) and were found to be shedding viral DNA in their semen on day 28 p.i. Viral DNA was identified in all semen fractions from all bulls, but mostly from the cell‐rich fraction and from the severely affected bulls. The PCR assay was positive on postmortem samples of testes and epididymides from the two severely affected bulls. Virus could be recovered from the testes of these two bulls and from the epididymis of one of them. Immunoperoxidase staining was positive for LSDV staining in sections of testes and epididymides exhibiting necrosis. This study suggests that the testis and epididymis are sites of persistence of LSDV in bulls shedding virus in semen for prolonged periods and revealed that viral DNA is present in all fractions of the ejaculate.  相似文献   
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The aim of this study was to determine the changes in diameter of corpus luteum (CL), maternal progesterone (P) concentration, lipid peroxidation and non‐enzymatic antioxidant levels along with enzymatic antioxidant activities in pregnant ewes bearing single and twin foetuses. The ewes were selected from healthy animals that were brought to the abattoir for slaughtering. The ewes were divided into three groups: Group 1 (non‐pregnant, non‐oestrous, n = 30), Group 2 (pregnant bearing a single foetus, n = 30) and Group 3 (pregnant bearing twin foetuses, n = 12) after they were slaughtered. Pregnant ewes were in the first half of the pregnancy. The diameter of CL and P concentration of pregnant ewes bearing a single foetus or twin foetuses were found higher than that found in non‐pregnant ewes. Similarly, the P concentration of pregnant ewes bearing twin foetuses was higher than that found in pregnant ewes bearing a single foetus. Malondialdehyde (MDA) level in pregnant ewes bearing twin foetuses was higher than that found in both non‐pregnant and pregnant ewes bearing a single foetus. The serum glutathione (GSH) level and glutathione‐peroxidase (GSH‐Px) activity of pregnant ewes bearing twin foetuses were found lower than that found in non‐pregnant ewes. Additionally, the GSH‐Px activity of pregnant ewes bearing twin foetuses was found lower than that found in pregnant ewes bearing a single foetus. No significant difference was found between pregnant ewes bearing female and male foetus with respect to diameter of CL, P concentration and oxidative stress parameters. There were significant positive correlations between foetal number (0, 1, 2) and diameter of CL, P concentration, MDA level, and between P concentration and diameter of CL, MDA level. However, significant negative correlations were found between foetal number (0, 1, 2) and GSH level, GSH‐Px activity, and between P concentration and GSH‐Px activity. In conclusion, the diameter of CL enlarges, P production increases and oxidant/antioxidant balance impairs because of the gestation stress in ewes during pregnancy.  相似文献   
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Since the teleost pronephros is an important source of diverse immunocytes, suspensions of pronephric cells from young adult carp have been characterized. In freshly prepared suspensions, adherent, spreading cells (macrophages?) constituted less than 3% of the total population. Granulocytes and lymphocytes were co-dominant (less than 80%) leucocyte types. Continuous Percoll density gradient centrifugation yielded discrete subpopulations with these rho values and cytological characteristics: Fraction I & II rho = 1.055-1.070 thrombocytes, monocytes, macrophages, and lymphocytes. Fraction III rho = 1.080-1.090 granulocytes, type 1. Fraction IV rho = 1.105-1.110 erythrocytes and granulocytes, type 2. Fraction V rho = 1.118-1.125 granulocytes, type 3. Fraction VI rho = 1.140-1.150 granulocytes, type 4. Granulocyte motility increased markedly over the first 24 hr in vitro, and was enhanced by components washed from intact yeast. The subtypes of granulocytes were distinguishable by not only the rho values, but also on the basis of cell size, ultra-structure of the granules, and their histochemical and phagocytic characteristics. After simultaneous in vivo injection of Bacillus megaterium (Gram + ve), Aeromonas hydrophila (Gram - ve) and Saccharomyces cerevisiae (yeast), individual pronephric leucocytes were found capable of phagocytosing all three types of particle. Granulocytes which had phagocytosed B. megaterium were slower than macrophages in their ability to kill the bacteria. Encounter with B. megaterium or S. cerevisiae in vitro elicited a clumping reaction which involved mostly the larger leucocytes [granulocytes]. Both adherent cells and non-adherent cells were phagocytic in vitro.  相似文献   
7.

Context

Spatial scale is an important consideration for understanding how animals select habitat, and multi-scalar designs in resource selection studies have become increasingly common. Despite this, examination of functional responses in habitat selection at multiple scales is rare. The perceptual range of an animal changes as a function of vegetation association, suggesting that use, selection and functional responses may all be habitat- and scale-dependent.

Objectives

Our objective was to determine how varying grain size affects our interpretation of functional response in habitat selection and to elucidate scalar and landscape effects on habitat selection.

Methods

We quantified the functional response of GPS-collared, female white-tailed deer (Odocoileus virginianus, n = 18) in Riding Mountain National Park, Canada, to different habitat types. Functional responses were quantified at multiple spatial scales by regressing proportion of habitat used against proportion of habitat available at different buffer radii (ranging from 75–1000 m radius) surrounding used (telemetry) locations and available points within the individual’s seasonal home range. We examined how functional responses changed as a function of grain by plotting grain size against the slope of the functional response.

Results

We detected functional responses in most habitat types. As expected, functional responses tended to converge towards 1 (use proportional to availability) at large buffer sizes; however, the relationship between scale and functional response was typically non-linear and depended on habitat type.

Conclusions

We conclude that a multi-scalar approach to modelling animal functional responses in habitat selection is important for understanding patterns in animal behaviour and resource use.
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A 2-year-old intact male alpaca was presented for a post-breeding preputial prolapse of 5 days duration. The internal lamina of the prepuce was prolapsed approximately 6 cm and the exposed preputial epithelium was edematous and necrotic. Following 7 days of medical treatment, resolution of the preputial prolapse was achieved.  相似文献   
10.
Knight  Elly  Sólymos  Péter  Brigham  Mark  Bayne  Erin 《Landscape Ecology》2022,37(6):1509-1525
Landscape Ecology - Movement is one of the proposed explanations for the scale at which a species responds most strongly to its environment, or the “scale of effect”. Scarcity of...  相似文献   
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