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81.
A study with finishing lambs assessed the effect of dietary inclusion of Prosopis laevigata pods (PLPs) on performance, carcass characteristics, meat traits and fatty acid profile of subcutaneous fat. Twenty‐one Rambouillet lambs (27.0 ± 3.0 kg BW) were assigned to one of three experimental diets with 0, 150 and 300 g PLP/kg DM. Evaluation of growth performance lasted 49 days. The experimental design was completely randomized and analysed with a mixed model. Lambs fed diets with 0, 150 and 300 g PLP had similar growth performance. Lambs fed diets with 300 g PLP/kg DM had better (p < 0.05) carcass yield and classification, less (p < 0.05) fat deposition and lower lightness (L*) value (p < 0.05) in meat than lambs fed diets with 0 and 150 g PLP/kg DM. Saturated fatty acids (palmitic and stearic) decreased (p < 0.05) and unsaturated fatty acids (oleic and linoleic) increased (p < 0.05) in subcutaneous fat of lambs fed diets with 150 and 300 g pods as compared with lambs not fed PLP. Prosopis laevigata pods are a safe feedstuff that can replace a third of conventional ingredients and reduce feed costs in growing lambs. Addition of PLP reduced (p < 0.05) total feed cost by 21%.  相似文献   
82.
The distribution of T lymphocytes (CD3+), B lymphocytes (CD79+), immunoglobulin-containing plasma cells (IgG, IgM and IgA), macrophages (Mac387+) and MHC Class II antigen was analysed in the inflammatory infiltrate associated with cutaneous squamous cell carcinomas (SCC) from 23 cats. Peri-tumoural skin (12 cases) and precancerous lesions of actinic keratosis (nine cases) were also evaluated for the expression of MHC Class II. The results revealed that an abundant inflammatory infiltrate was associated with the majority of SCC. This infiltrate was composed mainly of CD3+ T lymphocytes, B cells (CD79+) and IgG-bearing plasma cells, and the intensity of infiltration increased with the degree of invasiveness of the tumour. The number of CD3+ T cells and CD79+ cells was significantly increased in well-differentiated SCC compared with moderately differentiated tumours, whereas the number of IgM+, IgA+ plasma cells and Mac387+ macrophages was low or moderate and did not change significantly with histologic grade or invasiveness. MHC Class II antigen was expressed by infiltrating lymphocytes and macrophages, and by fibroblasts. A variable number of neoplastic cells (10% to 80%) in 10 SCC, and keratinocytes of basal layers in seven of nine cases of actinic keratosis also expressed MHC Class II, whereas keratinocytes of normal skin were always negative for this antigen. These results suggest that CD3+ T lymphocytes, CD79+ B cells and IgG-bearing plasma cells may participate in down-regulation of tumour growth, since these cell types were particularly numerous in well-differentiated and mildly invasive SCC, as well as in actinic keratosis. The expression of MHC Class II by neoplastic cells could enhance this local anti-tumour immune response.  相似文献   
83.
The aim of the present study was to explore the usefulness of serological methods in the diagnosis of postweaning multisystemic wasting syndrome (PMWS). The study was carried out in 4 PMWS-affected and 6 control farms. Based on the serological profiles, infection with porcine circovirus type 2 (PCV2) was determined to take place at 3-7 weeks of age in the PMWS-affected and at 3-11 weeks of age in the control farms. To compare the dynamics of seroconversion to PCV2 among farms, cross-sectional serological profiles were normalised in relation to the inferred age of infection. The results indicated that the proportion of seropositive pigs increased significantly slower in the affected herds. The most pronounced difference was observed about 4 weeks after infection, when the proportion of seropositive pigs ranged from 0 to 53.3% and from 70 to 100% in PMWS-affected and control herds, respectively. Mean antibody titres at that age were also significantly lower in the affected farms. These observations suggest a delay in the production of PCV2-specific antibodies and indicate that serological methods may be helpful in identifying herds with a high risk of PMWS.  相似文献   
84.
85.
A total of 50 Escherichia coli strains isolated in a Libyan hospital (20 from children with diarrhoea and 30 from healthy children) were investigated for their pathotypes and virulence traits. Altogether nine eae-positive (enteropathogenic E. coli, EPEC) and nine aggR-positive (entero-aggregative E. coli, EAEC) strains were identified. Significantly (P=0.001) more EPEC strains were identified from diarrhoeal patients (n=8) than from healthy controls (n=1), while six EAEC strains were identified from diarrhoeal and three from healthy children. Typical (eae(+), EAF(+), bfp(+)) EPEC strains (n=6) belonged to classical EPEC serogroups O55, O114, O127 and showed localized adherence on Hela cells. EAEC strains revealed genetic heterogeneity but uniformly adhered to HeLa cultures in an entero-aggregative adherence pattern. Antibiotic resistance frequently, characterized the strains. Sixty-eight percentage of the strains were resistant against at least one antibiotic and 30% harbored a class 1 integron independently of their clinical background. This is the first report from North Africa demonstrating the significance of EPEC and EAEC.  相似文献   
86.
The control of sheep nematode parasites in extensive mountain/transhumant management systems using the nematophagous fungus Duddingtonia flagrans was assessed in this study. Two groups of Churra Tensina ewes were allowed to graze for 8 weeks in autumn on two separate paddocks of infected pasture near their winter sheds in the valley. At lambing, ewes and their twin lambs were turned out into the same paddocks for the following 12 weeks. One group of ewes received a daily dose of 5 x 10(5) chlamydospores of Duddingtonia flagrans/kg live weight per day both in autumn and in spring, while the other group was used as a non-treated control. Daily dosing of grazing ewes with the fungus D. flagrans had a clear effect on reducing autumn pasture contamination. This had a subsequent effect on the over-wintering larvae population that was confirmed by a 20% lower worm burden of tracer lambs kept in early spring on the paddock previously grazed by fungus treated ewes. In spring, pasture contamination was also significantly reduced in the paddock grazed by fungi-treated ewes and their lambs showed a 61% lower worm burden and a better performance than the control lambs. Results herein show that fungal spores fed to sheep at critical times with regard to the epidemiology of parasite infection, can have a significant effect on the infective larvae present on pasture, which could further improve lambs performance. This novel approach to parasite control would be of interest amongst both organic and conventional sheep farmers operating in mountain regions.  相似文献   
87.
REASONS FOR PERFORMING STUDY: Danofloxacin is a fluoroquinolone developed for veterinary medicine showing an excellent activity. However, danofloxacin pharmacokinetics profile have not been studied in horses previously. OBJECTIVE: To study the pharmacokinetics following i.v., i.m. and intragastric (i.g.) administration of 1.25 mg/kg bwt danofloxacin to 6 healthy horses. METHODS: A cross-over design was used in 3 phases (2 x 2 x 2), with 2 washout periods of 15 days (n = 6). Danofloxacin (18%) was administered by i.v. and i.m. routes at single doses of 1.25 mg/kg bwt. For i.g. administration an oral solution was prepared and administered via nasogastric tube. Danofloxacin concentrations were determined by HPLC assay with fluorescence detection. Tolerability at the the site of i.m. injection was monitored by creatine kinase (CK) activity. RESULTS: Danofloxacin plasma concentration vs. time data after i.v. and i.g. administration could best be described by a 2-compartment open model. The disposition of i.m. administered danofloxacin was best described by a one-compartment model. The terminal half-lives for i.v., i.m. and i.g. routes were 6.31, 5.36 and 4.74 h, respectively. Clearance value after i.v. dosing was 0.34 l/kg bwt/h. After i.m. administration, absolute bioavailability was mean +/- s.d. 88.48 +/- 11.10% and Cmax was 0.35 +/- 0.05 mg/l. After i.g. administration, absolute bioavailability was 22.36 +/- 6.84% and Cmax 0.21 +/- 0.07 mg/l. CK activity following i.m. dosing increased 3-fold over pre-injection levels 12 h after dosing and subsequently approached (but did not reach) normal values at 72 h post dose. CONCLUSIONS: Systemic danofloxacin exposure achieved in horses following i.m. administration was consistent with the predicted blood levels needed for a positive therapeutic outcome for many equine infections. Conversely, danofloxacin utility by the i.g. route was limited by low bioavailability. Tolerability associated with i.m. administration was high. POTENTIAL RELEVANCE: Pharmacokinetics, blood levels and good tolerability of i.v. and i.m. administration of danofloxacin in horses indicates that it is likely to be effective for treating sensitive bacterial infections.  相似文献   
88.
This study describes the distribution of galanin (Gal) and galanin receptor 2 (GalR2) in the pre‐optic area (POA) of the female guinea pig. Frozen sections were undergone for a routine immunofluorescence labelling. Gal and GalR2 display immunoreactivity in all parts of the pre‐optic area. Gal shows reactivity both in perikarya and fibres, whereas GalR2 was observed only in perikarya. Gal‐ and GalR2‐immunoreactive (‐ir) perikarya were the most numerous in the medial pre‐optic area (MPA) with the highest reactivity in its dorsal part. In the median pre‐optic nucleus (MPN) and periventricular pre‐optic nucleus (PPN), only single Gal‐ and GalR2‐ir neurons were observed. The highest density of Gal‐ir fibres was revealed in the PPN and the lowest in the lateral pre‐optic area (LPA). The results of this study indicate that the distribution pattern of Gal containing neurons overlaps well with the distribution pattern of GalR2‐positive neurons, especially in the MPA. This may suggest GalR2‐dependent activity in this brain region.  相似文献   
89.
The aim of this study was to characterize the vocalizations produced during electroejaculation under general anaesthesia in pampas deer males and to determine whether the characteristics of those vocalizations differ in adult and young pampas deer males. Electroejaculation was applied to 13 adults (AM) and 13 young (YM) males under general anaesthesia. Vocalizations were digitally recorded, and the number and duration of vocalizations, the latency in relation to each voltage, the total time vocalizing, and the structure of the fundamental frequency (F0) [initial frequency (Fstart), maximal frequency (Fmax), minimal frequency (Fmin) and final frequency (Fend)] were analysed. No male vocalized with 0 V; the number of animals that vocalized increased at 2 and 3 V and increased again at 4, 5 and 6 V (p < 0.05). The latency time from the beginning of each series (each voltage) decreased until 4 V (p < 0.01). The number of vocalizations/voltage increased from 4 V (p < 0.05). The length of each vocalization and the total time during which animals vocalized were greater in YM than AM (p = 0.02 and p = 0.01, respectively). Similarly, the fundamental frequencies were higher in YM than AM (p ≤ 0.05). Overall, we concluded that the vocalizations emitted during electroejaculation in pampas deer under general anaesthesia are related to the voltage applied during the process. Young males vocalize more time, probably due to a greater sensibility to the electric stimulation. The differences in the characteristics of the vocalizations between adult and young males may be related to the anatomic differences in the neck of adult or young males.  相似文献   
90.
Objectives were to determine associations between percentage pregnancy loss (PPL) in dairy cattle and: (i) pregnancy diagnosis by ultrasonography; (ii) pregnancy diagnosis by serum pregnancy‐specific protein B (PSPB) concentrations, with or without serum progesterone concentrations; and (iii) production and environmental factors. This study included 149 822 pregnancy diagnoses conducted over 13 years in Holstein‐Friesian cows in Hungarian dairy herds. The following were determined: PPL in cows diagnosed pregnant by transrectal ultrasonography 29–42 days after artificial insemination (AI; n = 11 457); PPL in cows diagnosed pregnant by serum PSPB 29–35 days after AI (n = 138 365); and PPL and its association with serum progesterone concentrations, PSPB and production/environmental variables. The definition of PPL was percentage of cows initially diagnosed pregnant based on ultrasonography or PSPB, but not pregnant when examined by transrectal palpation 60 –70 days after AI. The PPL was lower (p < 0.001) in cows following ultrasonographic vs PSPB diagnosis of pregnancy at 29–35 days (8.1 vs 19.3%, respectively), but was higher in cows following ultrasonographic pregnancy diagnosis on 29–35 vs 36–42 days (8.1 vs 7.1%, respectively, P < 0.05). Furthermore, 72.9% of pregnancies with ultrasound‐detected morphological abnormalities resulted in pregnancy loss. As a subset of PSPB data, a fully quantitative PSPB assay was used for 20 430 samples; PPL in cows with a high PSPB concentration (>1.1 ng/ml) was lowest (15.0%), whereas cows with low concentrations of both PSPB and progesterone (0.6–1.1 and <2 ng/ml, respectively) had the highest PPL (76.3%; p < 0.0001). Furthermore, PPL was higher in cows with advanced parity and with high milk production, when ambient temperatures were high, although body condition score (BCS) had no effect on PPL. Finally, there were no significant associations between serum PSPB and environmental temperatures or number of post‐partum uterine treatments.  相似文献   
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