MENSURATION OF THE NORMAL PITUITARY GLAND FROM MAGNETIC RESONANCE IMAGES IN 96 DOGS

The pituitary gland was measured from transverse magnetic resonance T1-weighted images after Gadolinium administration in 96 dogs weighing from 13 to 45 kg. The measurements were done by hand with calipers. The mean (+/- standard deviation) pituitary gland height was 5.1 mm (+/-0.9 mm). The mean width was 6.4 mm (+/- 1.1 mm). The correlation coefficient between pituitary and brain measurements, between pituitary measurement and body weight, and brain measurements and body weight was 0.0 to 0.3. A hyperintense region was present on T1-weighted images in the center of the pituitary gland in 64% of the dogs. At necropsy the pituitary glands were grossly and histologically normal. No pituitary gland measurements were performed at necropsy.     

蛋雏鸡传染性喉气管炎的诊治

鸡传染性喉气管炎(ILT)是由鸡传染性喉气管炎病毒引起的以剧烈咳嗽、气喘、高度呼吸困难和气管内有血样渗出物等为特征的一种急性呼吸道传染病.育成蛋鸡感染该病多有报道,而蛋雏鸡感染发病比较少见.本文以一起48日龄海兰褐蛋雏鸡传染性喉气管炎病例为题材,从发病情况、临床症状、病理剖检变化、诊断、防治等几个方面对该病做了详尽阐述.     

猪败血性链球菌与附红细胞体混合感染病例

猪败血性链球菌病是猪链球菌感染引起的一种急性败血性传染病,猪附红细胞体病是由猪附红细胞体寄生于猪红细胞而引起的一种散在的热性、溶血性传染病.本文以某猪场这2种病混合感染病例为题材,从发病基本情况、临床症状、剖检变化、实验室检验、防治措施等6个方面对该混合感染病例做了详尽的阐述.     

Incidence of reinfections with Mycoplasma hyopneumoniae and Actinobacillus pleuropneumoniae in pig farms located in respiratory-disease-free regions of Switzerland--identification and quantification of risk factors

The objective of the study was to identify risk factors for reintroduction of Actinobacillus pleuopneumoniae and Mycoplasma hyopneumoniae (enzootic pneumonia) onto pig farms in areas in Switzerland that were involved in an eradication programme from 1996 to 1999 and to assess the role of dealers in relation to these reinfections. The study was based on the comparison of pig farms that were reinfected in the year 2000 (cases) and pig farms that remained uninfected in the same area (controls). Additionally, data were collected from Swiss pig dealers and transport companies. Out of a total of 3983 farms, 107 farms were reinfected in the year 2000. The incidences were 0.1% for Actinobacillus pleuopneumoniae and 2.6% for Mycoplasma hyopneumoniae (enzootic pneumonia). Compared to reinfection rates prior to the eradication programme, this is a considerable reduction. Statistically significant risk factors for the reinfection were 'finishing farm', 'large mixed breeding-finishing farm', 'reinfected neighbour' and 'parking site for pig transport vehicles close to the farm'. Pig farmers that purchased pigs from only one supplier per batch had a lower risk of reintroducing infection (protective factor). As long as infected and uninfected regions co-exist in Switzerland, direct and indirect contact between farms, pig herds and slaughter sites via transport vehicles are a major pathway of disease spread. Risk management measures linked to these contacts are therefore of key importance. The survey of dealers indicated various areas for improvement such as strategic planning of pick-up routes or cleaning and disinfecting of trucks.     

Lysosomal Fragility in Earthworms (Eisenia Veneta) Exposed to Heavy Metal Contaminated Soils from Two Abandoned Pyrite Ore Mines in Southern Norway

In this study we have investigated the toxicity of soils from thetwo abandoned pyrite mines Ertelien and Konnerud in the southernpart of Norway. Soil samples were collected close to the pitheadof the mines, and earthworms were exposed to different concentrations of the contaminated mine soil mixed with commercial plant soil for a period of 14 days. Life-cycle responses such as growth and survival, as well as the biomarkerresponse lysosomal fragility were measured. The body burdens ofthe four heavy metals Cu, Cd, Zn and Pb were detected in the worms, and the body concentration of the metals generally increased with increasing heavy metal concentration in the soil.The growth and mortality of the earthworms were not influenced when exposed to any of the mine soil concentrations used. The lysosomal fragility of the earthworm coelomocytes measured by the neutral red retention time (NRR-time) was found to be markedly reduced in all the exposed earthworms. This assay seemsto be a sensitive and dose dependent endpoint for the toxicity assessment of heavy metal mixtures in pyrite mine soils.     

Gonadotropin‐Releasing Hormone Administration to Dairy Cows without a Corpus Luteum 4 Weeks after Calving Increases Reproductive Performance

This field study investigated whether the administration of a single dose of gonadotropin‐releasing hormone (GnRH) to dairy cows without a corpus luteum (CL) 4 weeks after calving can improve reproductive performance. Holstein dairy cows underwent ultrasonography to assess the presence of ovarian structures at 29.2 ± 5.2 days post‐partum, and cows were divided into two main groups based on the presence (CL group, n = 230) or absence (non‐CL group, n = 460) of a CL. The non‐CL group was further randomly divided into two subgroups based on the administration of GnRH (non‐CL GnRH group, n = 230) or no GnRH (non‐CL control group, n = 230). Subsets of cows from non‐CL control (n = 166) and non‐CL GnRH (n = 175) groups received a second ultrasonography at 44.5 ± 5.4 days post‐partum to assess CL formation. The percentage of cows with CL at the second ultrasonography was greater in the non‐CL GnRH group (70.9%) than in the non‐CL control group (53.0%, p = 0.0006). The hazard of the first post‐partum insemination by 150 days in milk (DIM) was higher in the CL group than in the non‐CL control group (hazard ratio [HR]: 1.36, p = 0.001). The probability of a pregnancy to the first insemination was higher in non‐CL GnRH (odds ratio [OR]: 1.50, p = 0.04) and CL groups (OR: 1.55, p = 0.03) compared to the non‐CL control group. Furthermore, the hazard of pregnancy by 210 DIM was higher in non‐CL GnRH (HR: 1.30, p = 0.01) and CL (HR: 1.51, p = 0.0001) groups than in the non‐CL control group. In conclusion, administration of GnRH to dairy cows without a CL 4 weeks after calving was associated with an increase in ovulation and improved reproductive performance.     

Hematologic values in calves during the first 6 months of life

BACKGROUND: Age-related changes in hematologic values are known to occur in many species. Few published studies include repeated measurements of hematologic parameters in calves during the first months of life. OBJECTIVE: The aim of the present study was to monitor hematologic values by sequential measurements from birth to 6 months of age in 15 healthy calves of the Norwegian Red breed, and compare the results to reference intervals for adult, lactating dairy cows. METHODS: Fifteen clinically healthy calves were sampled every week during the first 5 weeks of life and every month thereafter until 6 months of age. Hematologic values were measured using the ADVIA 120 hematology system. Reference intervals were determined for 75 healthy adult cows of the same breed. RESULTS: Compared with adult reference intervals, the MCV was lower and the RBC count was higher in calves throughout the investigation period. Hemoglobin concentration stayed largely within the adult reference interval. Mean MCHC was lower than adult values for 5 weeks, then increased and reached adult values by weeks 10-12. The mean lymphocyte count for calves reached adult reference values at weeks 6-8, and the mean monocyte count increased steadily until weeks 14-16. For most leukocytes, interindividual variation was larger during the first 5-8 weeks of life. The mean platelet count for calves was higher than the adult reference interval until weeks 19-21 of age. CONCLUSIONS: Age-specific reference intervals for calves from birth to 6 month of age are needed for RBC count, MCV, MCHC, red cell distribution width, and platelet and lymphocyte counts.     

A prospective study on canine hip dysplasia and growth in a cohort of four large breeds in Norway (1998-2001)

The study-objective was to measure the effect of weight and growth related parameters on the risk of development of Canine Hip Dysplasia (CHD). The hypothesis was that heavy and fast growing dogs of large sized breeds were at increased risk of development of CHD compared to lighter and slower growing dogs. A prospective cohort study was conducted among dogs of four large breeds: Newfoundland (NF), Leonberger (LEO), Labrador retriever (LR), and Irish wolfhound (IW). The dogs were privately owned with individualized nutrition and environment, and they were followed from birth and throughout the growth period until the official screening for CHD was performed. The study sample consisted of 501 dogs from 103 litters, with the breed distribution 125 NF, 180 LEO, 133 LR, and 63 IW. Because the dogs were clustered in litters a multivariable random effects logistic regression model was used to assess statistically significant growth-related risk factors for CHD. The estimated incidence risk of CHD was 36% in NF, 25% in LEO, 20% in LR, and 10% in IW. Based upon the final multilevel model it appears that the odds of CHD among both LR and IW (odds ratio (OR) 0.22) are about one-fifth of the odds for NF. The odds for LEO (OR 0.60) are not significantly different from NF. There appeared to be an inverse relationship between body weight at 3 months of age and odds of CHD, with an OR of 0.89 (P=0.044). The degree of clustering at the litter-level was high (22.6%) and highly significant (P<0.001). Findings failed to support the hypothesis that heavy and fast growing dogs from four large sized breeds were at increased risk for development of CHD. There might be other unmeasured environmental risk factors for CHD in this cohort of dogs, although the contribution of the genetic variance to the litter-level clustering also needs further investigation.     

Erträge und N‐verbleib im internationalen organischen stickstoffdauerdüngungsversuch (IOSDV) puch

Im Internationalen Organischen Stickstoffdauerdüngungsversuch (IOSDV) Puch wurde 1998, nach 15 Versuchsjahren, die 5. Rotation abgeschlossen. Der Versuch umfaßt 10 Düngungsvarianten mit organischen Stoffen, die den Bewirtschaftungsformen mit und ohne Vieh entsprechen. Zusätzlich wurden im Mittel über die Fruchtfolge 0, 40, 80, 120 und 160 kg/ha mineralischer Stickstoff verabreicht. Angebaut wurde eine 3‐jährige Fruchtfolge mit Silomais oder Zuckerrüben, gefolgt von Winterweizen und Wintergerste. Bei der Auswertung des Versuches wurde die erste Rotation, die Anlaufphase, nicht berücksichtigt.

Von den organischen Düngern brachte Gülle, allein oder zusammen mit Stroh bzw. mit Stroh und Zwischenfrucht (Senf) die höchsten Mehrerträge (im Mittel 14%), es folgen Stallmist (6%), Rübenblatt (5%) und Leguminosen‐Zwischenfrucht (4–5%). Stroh allein führte zu Mindererträgen.

Die organischen Dünger führen auch zu Humusneubildung, in dem ein Teil des ausgebrachten Stickstoffes gespeichert wird. Dies muß in den N‐Salden berücksichtigt werden.

Bei alleiniger Strohdüngung wird mehr Stickstoff im neugebildeten Humus gespeichert als mit dem Stroh zugeführt wird, daher auch die niedrigeren Erträge dieser Variante. Bei den Düngungsvarianten Gülle + Stroh, Rübenblatt + Stroh und Leguminosen ‐Zwischenfrucht + Stroh führt Stroh zur Reduzierung von N‐Verlusten.

Die höchsten Humusmengen wurden nach Düngung mit Gülle + Stroh + Zwischenfrucht und Stroh + Zwischenfrucht + Rübenblatt gebildet.