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21.
Examination of two collections of Donax serra from a South African west coast beach revealed the presence of Ciliophora, Trematoda, Nematoda and a parasitic pycnogonid. This is the first record of a pycnogonid from the genus Donax and the first published report of such a parasite from any southern African bivalve mollusc. One of the two trematode species found is described as new and its epidemiology is discussed briefly. No epibiota were found on the bivalve shell. 相似文献
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A pregnant quarterhorse mare became acutely lame as a result of severe swelling of its right hind leg, thought to have been caused by a fracture or a muscle tear. Diagnostic procedures ruled out a traumatic musculoskeletal cause and a physical examination revealed chronic pastern dermatitis ('scratches'/'grease heel'). Histopathological evaluation of biopsy samples from the right hind leg was consistent with a leucocytoclastic vasculitis, and culture yielded Staphylococcus intermedius. The treatment and infectious causes of pastern dermatitis are discussed. 相似文献
24.
An Economic Opportunity Survey was conducted on dairy farms in the North West Province of Cameroon. Results showed that median
(range) number of cows in milk per farm was zero point six (0–4) and six (3–12) in the zero grazing and transhumance systems,
respectively. Medians (range) of three (0–24) and four (3–10) litres of milk were sold per farm per day, corresponding to
30% and 60% of milk produced. 24% and 13% of total cattle per herd were milking cows in the zero grazing and transhumance
systems respectively. Median milk production per cow on one day was two (0–25) and two (1–3) litres. Median calf production
interval was 14.5 (12–25) and. 21.5 (14–29) months. More milk produced per day represented the best economic opportunity in
both systems while reduced age at first calving and longer lactation length were the next in both. Wastage of milk through
spoilage from poor hygiene and lack of cooling was a major problem. Holstein cows, which were in the zero grazing system,
had unexpectedly short lactations. Constraints identified led to the setting up of interventions of training and advice for
farmers and of better nutrition. 相似文献
25.
Groups of chicks were given diets containing cholecalciferol or ergocalciferol supplemented with 0, 0-1, 1 or 10 g ergosterol/kg. 2. Ergosterol had no significant effect on growth, on the plasma concentration of calcium or on the content of bone-ash, indicating that it did not impair the absorption of either form of vitamin D. 3. An explanation is given for the apparent disagreement in the published findings on the relative anti-rachitic potencies of ergocalciferol and cholecalciferol in the chick. 相似文献
26.
Santiago Peralta Suzin M. Webb William P. Katt Jennifer K. Grenier Gerald E. Duhamel 《Veterinary and comparative oncology》2023,21(1):138-144
Oral squamous cell carcinoma (OSCC) is the most common oral epithelial malignancy in dogs. It exhibits locally aggressive biological behaviour with the potential to metastasize, and a reported 1-year survival rate of 0% when left untreated. Expression studies suggest that aberrant MAPK signalling plays a key role in canine OSCC tumorigenesis, which is consistent with BRAF and HRAS MAPK-activating mutations reported in some tumours. Several morphological subtypes of canine OSCC have been described, with papillary, conventional, and basaloid as the most common patterns. We hypothesized that mutational differences may underlie these phenotypic variations. In this study, targeted Sanger sequencing and restriction fragment length polymorphism assays demonstrate that up to 85.7% of canine papillary OSCC (n = 14) harbour a BRAF p.V595E mutation. Assessment of neoplastic epithelial cell proliferation using Ki67 immunolabelling (n = 10) confirmed a relatively high proliferation activity, consistent with their known aggressive clinical behaviour. These findings underscore a consistent genetic feature of canine papillary OSCC and provide a basis for the development of novel diagnostic and targeted therapeutic approaches that can improve the quality of veterinary care. 相似文献
27.
S R Arthur E T Kornegay H R Thomas H P Veit D R Notter K E Webb J L Baker 《Journal of animal science》1983,57(5):1200-1214
The effect of early nutrition on subsequent bone development was studied using gilts that had previously been fed ad libitum or 75% ad libitum intake and 100 or 150% National Research Council-recommended daily Ca and P from weaning to 100 kg. During the three-parity reproductive study, sows were fed a 14% protein diet. Metacarpals and metatarsals were taken from sows culled due to lameness or failure to breed and from sows after completing three parities. Femur and humerus articular cartilage and turbinates were described at necropsy. Metacarpals and metatarsals were heavier and tended to have thicker walls when sows were previously fed ad libitum or fed 150% Ca and P. Energy intake produced the greater response. Metacarpal breaking strength was greatest for sows previously fed ad libitum. Metatarsals were not affected by energy intake. Stiffness, Young's modulus of elasticity (YME) and flexural modulus for metacarpals and metatarsals were not affected by energy intake. Previously fed Ca and P intakes did not affect any of the mechanical bone characteristics. Metacarpals were heavier, had a greater breaking strength, were more elastic and exhibited slightly less resistance to bending than the metatarsals. The ether extract, ash, Ca and P content and the Ca:P ratio of metacarpals and metatarsals were not affected by previously fed energy or Ca and P intakes. The ether extract content tended to decrease and the ash, Ca and P content tended to increase with age. Articular cartilage and turbinate scores were not influenced by previously fed energy or Ca and P intakes. The YME and flexural modulus were the only bone characteristics that were even poorly correlated (average r = .25) with soundness scores, suggesting that high values result in poorer soundness scores. Energy and Ca and P intakes during growth and development had only minimal effects on bone characteristics and no apparent effect on structural soundness and longevity of sows kept for three parities. 相似文献
28.
Effect of dietary potassium on absorption of magnesium and other macroelements in sheep fed different levels of magnesium 总被引:1,自引:0,他引:1
Two metabolism trials were conducted with 24 crossbred wether lambs. Two levels of Mg (.1 and .2%) and four levels of K (.6, 1.2, 2.4 and 4.8%) were fed in a 2 x 4 factorial arrangement of treatments. Each trial consisted of a 10-d preliminary period followed by a 10-d collection of feed, feces and urine. Increasing levels of dietary K resulted in a linear increase in fecal Mg excretion and a linear decrease in Mg absorption. A large depression in Mg absorption occurred when K was increased from 1.2 to 2.4% with a further decrease when K was increased to 4.8%. Lambs fed the high level of Mg (.2%) absorbed and retained more (P less than .05) total Mg (g/d, but not percentage of intake) compared with the low magnesium level (.1%). Dietary Mg did not affect the amount of K excreted, absorbed or retained. Increasing the level of dietary K resulted in a linear increase in urinary, fecal and total K excreted, absorbed and retained (P less than .05). 相似文献
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