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101.
Prenatal growth is very complex and a highly integrated process. Both maternal nutrition and the maternal somatotropic axis play a significant role in coordinating nutrient partitioning and utilization between maternal, placental and fetal tissues. Maternal nutrition may alter the nutrient concentrations and in turn the expression of growth regulating factors such as IGFs and IGFBPs in the blood and tissues, while GH acts in parallel via changing IGFs/IGFBPs and nutrient availability. The similarity in the target components implies that maternal nutrition and the somatotropic axis are closely related to each other and may induce similar effects on placental and fetal growth. Severe restriction of nutrients throughout gestation has a permanent negative effect on fetal and postnatal growth, whereas the effects of both temporary restriction and feeding above requirements during gestation seem to be of transitional character. Advantages in fetal growth gained by maternal growth hormone treatment during early to mid-gestation are not maintained to term, whereas treatment during late or greatest part of gestation increases progeny size at birth, which could be of advantage for postnatal growth. This review summarizes the available knowledge on the effects of different maternal feeding strategies and maternal GH administration during pregnancy and their interactions on metabolic and hormonal (especially IGFs/IGFBPs) status in the feto-maternal unit, skeletal muscle development and growth of the offspring in pigs.  相似文献   
102.
Vibrionic hepatitis is a disease of poultry which is characterised by the presence of focal lesions in the liver, usually 1-2mm in size and greyish-white in colour. The cause of the disease remains unclear, as do the reasons for its recent re-emergence. We examined the livers of commercial broiler chickens taken during processing and found Campylobacter spp. in both normal livers and those displaying signs indicative of focal hepatitis. Livers with signs of hepatitis had significantly more Campylobacter spp. present than those without and other bacterial genera were infrequently present. We were unable to replicate the disease in a healthy host following experimental infection with a Campylobacter jejuni strain isolated from a liver showing signs of focal hepatitis. However, a significant T cell response to C. jejuni was seen in the liver of Campylobacter infected birds. We conclude that the presence of Campylobacter spp. in the liver alone is not sufficient to cause vibrionic hepatitis, but that a predisposing factor, possibly within the host is required. We also provide evidence that chickens mount an adaptive T cell response to systemic C. jejuni.  相似文献   
103.
The aim of this study was to investigate the seroprevalences to zoonotic pathogens in hunters, to propose preventive measures and to obtain more information about the occurrence of zoonotic pathogens in local wild animal populations. From 146 male and 3 female hunters originating from the south-eastern Austrian federal states of Styria and Burgenland blood samples were taken and anamnestic data were obtained using a questionnaire. The serological investigations included the following viral, bacterial and parasitic zoonotic agents or zoonoses, respectively (antibody-seroprevalences in brackets): encephalomyocarditis virus (EMCV, 15%), Puumala-Hantavirus (10%), Newcastle Disease virus (NDV, 4%), borreliosis (IgG 42%, IgM 7%), brucellosis (1%), chlamydiosis (3%), ehrlichiosis (IgG 15%, IgM 3%), leptospirosis (10%), tularaemia (3%), Q fever (0%), Echinococcus multilocularis/E. granulosus (5%/11%), toxocariasis (17%). Out of a control group of 50 persons (urban population, no hunters) only one person was found to be seropositive for Toxocara canis and NDV and four for EMCV, all other results were negative in the control group. The high seroprevalences especially to Borrelia burgdorferi s.l., Ehrlichia spp., Leptospira interrogans, E. granulosus, E. multilocularis, encephalomyocarditis virus and Puumala virus demonstrate that hunters are particularly exposed to zoonotic pathogens. It should also be noted that one hunter was seropositive for Brucella abortus and five exhibited antibodies to Francisella tularensis. In these cases, as well as in the cases of the 15 seropositives for Leptospira interrogans, the suspected source of infection may--besides rodents--also include wild boars and brown hares. The infections with NDV and Chlamydophila psittaci may be traced back to contact with certain species of birds (potential risk: aviaries). For Hantaviruses, rodents are considered to be the main source of human infections.  相似文献   
104.
105.
106.

Background

The objective of this study was to investigate the association between average daily gain and the number of Lawsonia intracellularis bacteria in faeces of growing pigs with different levels of diarrhoea.

Methods

A longitudinal field study (n = 150 pigs) was performed in a Danish herd from day 29 to 47 post weaning. Every third day all pigs were weighed, subjected to a clinical examination and faecal samples were obtained. Faecal samples were subjected to dry matter determination and absolute quantification by PCR for L. intracellularis and porcine circovirus type 2 (PCV2). Association between average daily gain, faecal dry matter content, numbers of L. intracellularis bacteria and PCV2 genome copies in faeces was investigated in a multilevel mixed-effects linear model.

Results

Increasing numbers of L. intracellularis log10 bacteria/g faeces were significantly associated with decreasing average daily gain (P < 0.001). The association was decreasing with increasing faecal dry matter content (P < 0.01). The number of PCV2 log10 copies/g faeces was not significantly associated with average daily gain of the pigs (P > 0.5).

Conclusion

The results suggest a potential application of a PCR quantifying L. intracellularis in growing pigs. Faecal dry matter content must be taken into consideration in interpretation of such test results.  相似文献   
107.
The objective of this study was to compare the sedative and peripheral hemodynamic effects of acepromazine (ACP) and promethazine (PTZ) in the standing healthy horse. Nine healthy Warmblood horses randomly received either intravenous ACP at 0.1 mg/kg or PTZ at 0.1, 0.2, and 0.3 mg/kg. A sedation score based on clinical examination was recorded, and systolic arterial blood pressure was noninvasively evaluated using a Doppler flow detector at the tail, just before and every 15 minutes until 60 minutes after drug injection. Hemodynamics of the median artery of the left forelimb was studied using Doppler ultrasonography just before and 45 minutes after injection of the drug, which allowed calculation of surface (SURF), diameter (DIAM), and circumference (CIRC) of the vessel and peak systolic velocity (PSV), end diastolic velocity (EDV), mean velocity (MV), volumetric flow (VF), and resistivity index (RI) of the blood flow. Regardless of the dose used, PTZ had lesser sedative and hypotensive effects than ACP at 0.1 mg/kg and did not induce significant variations in SURF, DIAM, CIRC, PSV, EDV, MV, VF, and RI of the studied standing horses. Conversely, the vasodilatory properties of ACP were illustrated by a significant increase in SURF, DIAM, CIRC, PSV, EDV, MV, and VF and a significant reduction of the RI. Unlike ACP, PTZ did not induce alterations on the morphology of the Doppler waveform. PTZ appears to have less sedative and peripheral vasodilator effects than ACP, thus it could be safer than ACP in patients suffering from hypotension.  相似文献   
108.
Objectives(1) To investigate heart morphology and function using echocardiography and tissue Doppler imaging (TDI), (2) to determine heart disease prevalence and characteristics, and (3) to assess potential genetic features in a population of Sphynx cats presented for cardiovascular screening.AnimalsA total of 147 echocardiographic examinations, including 33 follow-ups, were performed by trained observers on 114 Sphynx cats of different ages (2.62 ± 1.93 years [0.5–10.0]) from 2004 to 2011.MethodsSphynx cats underwent a physical examination, conventional echocardiography, and, if possible, two-dimensional color TDI.ResultsConventional echocardiographic findings included 75/114 normal (65.8%) and 39/114 (34.2%) abnormal examinations with a diagnosis of either congenital heart diseases (n = 16) or hypertrophic cardiomyopathy (HCM, n = 23). In adult healthy cats, a significant body weight effect was observed for several echocardiographic variables, including end-diastolic left ventricular (LV) free wall (P < 0.01), interventricular septum (P < 0.001), and LV diameter (P < 0.001). Mitral valve dysplasia (MVD) was observed as a single or associated defect in 15/16 cats with congenital heart diseases. A significant increase in HCM prevalence (P < 0.001) was observed according to age. The pedigree analysis of a large family (n = 81) suggested an autosomal dominant mode of inheritance with incomplete penetrance for HCM.ConclusionsBody weight should be taken into account when interpreting values of diastolic myocardial wall thicknesses in Sphynx cats. Additionally, HCM and MVD are two relatively common heart diseases in this feline breed. More pedigree data are required to confirm the inheritance pattern of HCM at the breed level.  相似文献   
109.
Hemorrhagic pneumonia is an acute and fatal disease of farmed mink caused by Pseudomonas aeruginosa. The pathogenesis of this disease has not yet been resolved. Mink are the only animals known to be susceptible to acute, contagious, and fatal lung infections caused by P. aeruginosa. The purpose of this study was to investigate the correlation between dose-response and season of infection and to clarify whether Danish mink are carriers of P. aeruginosa on their nasal mucosa during the season for hemorrhagic pneumonia. To elucidate the pathogenesis of the disease, an infectious dose-response trial was carried out on adult mink and mink kits, both in the season for hemorrhagic pneumonia (November) as well as out of season (July). It proved difficult to infect mink via the intra-nasal route. Only 4 out of 60 infected mink developed clinical disease and were euthanized, all of them in November, illustrating that predisposing factors in the mink itself and not infectious dose might be crucial for disease development. We were able to culture P. aeruginosa from the nasal cavity of the clinically healthy experimental mink 8 d after inoculation. This indicated that the mink can carry P. aeruginosa on their nasal mucosa without developing the disease. It was not possible, however, to culture P. aeruginosa from the nasal cavity of clinically healthy mink obtained from farms in November, which indicates that the organism is not a normal part of the nasal mucosal flora of mink.  相似文献   
110.

Objective

To determine the dose of cis-atracurium needed to produce a moderate neuromuscular blockade (NMB) in pigs.

Study design

Prospective experimental study.

Animals

Seven pigs [five females and two males; median (range) body weight: 47 (36–64) kg].

Methods

Pigs were premedicated with intramuscular midazolam (0.3 mg kg?1) and ketamine (7 mg kg?1). Anaesthesia was induced with intravenous (IV) propofol 3 (1–4) mg kg?1 and maintained with isoflurane in oxygen. Based on a preliminary study, the subjects were administered 0.3 mg kg?1 cis-atracurium followed by 0.48 mg kg?1 hour?1 constant rate infusion (CRI) IV. A moderate NMB was defined as a train-of-four (TOF) count of ≤2 by acceleromyography. When the TOF count was >2, 0.1 mg kg?1 cis-atracurium was administered and the CRI was increased. The cis-atracurium CRI was decreased when the TOF count was under 2 for more than 15 minutes. The total dose of cis-atracurium required to maintain a moderate NMB was calculated as the total amount of cis-atracurium used (both CRI and supplementary boluses) divided by the administration time.

Results

The cis-atracurium CRI lasted for 87 (76–151) minutes. To induce and maintain a moderate neuromuscular blockade, the initial dose of cis-atracurium was 0.3 (0.3– 0.5) mg kg?1 and the CRI was 0.71 (0.37–0.98) mg kg?1 hour?1.

Conclusions and clinical relevance

The doses described in our study may help researchers obtain a moderate NMB using cis-atracurium in pigs.  相似文献   
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