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531.

Background

Lameness in piglets is a major animal welfare issue. Floor abrasiveness is a common cause of superficial injury in piglets in farrowing pens. The abrasion achieved may act as a gate for infections, which in turn may induce development of infectious arthritis. In this study, the influence of improvements of the floor quality and of increased ratios of straw in identical farrowing pens was measured.

Methods

The study was carried out at a herd with four identical farrowing units with solid concrete floor bedded with 1 kg chopped straw per sow and 1 hg per piglet and day. Nothing was changed in the management of the four identical farrowing units, but four experimental groups were created: Group I – control, Group II – the amount of bedding was doubled. The surface of the floor was repaired in two units, Group III – Piglet Floor®, Flowcrete Sweden AB, Perstorp, Sweden and Group IV – Thorocrete SL®, Växa Halland, Sweden. Three farrowing batches were studies in each unit. In total, 93 litters (1,073 piglets) were examined for foot and skin lesions until the age of 3 weeks. The occurrence of lameness was registered until weaning at an average age of 4.5 weeks. Twenty seven lame piglets were culled instead of medicinally treated and subjected to necropsy including histopathological and microbiological examinations. Isolates of streptococci, staphylococci and E. coli were tested with respect to antimicrobial resistance.

Results

Piglet born on the repaired floors had the lowest prevalences of abrasions at carpus. Also the doubled straw ration decreased the abrasions. Skin lesions at carpus decreased significantly in magnitude in all four systems from day 10. At day 3, the sole bruising scores of the control unit were greater than the other three units (p < 0.001). At day 10 and 17, sole bruising was less common in the units with repaired floors than in the control group and the group with doubled straw ration. In total 41 piglets were diagnosed as lame, corresponding to 3.8% of all live-born piglets (n = 1,073). Around 85% of these diagnoses took place during the first 3 weeks of life and the risk incidence of lameness decreased from 1.5% during the first week of life to 0.5% during the fourth week. The incidence of lameness was highest in the control unit and lowest in the units with repaired floors. Twenty lame piglets were confirmed to have bacterial growth in the joint. The causative agents were Streptococcus dysgalactiae subsp. equisimilis (60%), Staphylococcus hyicus subsp. hyicus (35%) and Escherichia coli (5%). These isolates were sensitive to all antibiotics included in the antimicrobial panels.

Conclusion

The results suggest that proper maintenance of the floor can prevent the degree of roughness and abrasiveness of the floors, which in turn can contribute significantly to prevention of abrasions, sole bruising and lameness in piglets. Maintaining the surface of concrete floors with two different commercially available solutions both decreased the incidence of abrasions and sole bruisings and thereby also of arthritis significantly. Also doubling the amount of chopped straw turned out to prevent development of skin lesions and sole bruisings to some extent, and subsequently also the incidence of arthritis.  相似文献   
532.

Background

Systematic pathological investigations to assess the health status of seabirds and coastal birds in Germany were performed. The investigation was conducted to obtain data on possible causes of decline in seabird and coastal bird populations.

Methods

48 individuals of 11 different species of seabirds and coastal birds were collected by the stranding network along the entire German North Sea coast from 1997 to 2008, including mainly waders such as Eurasian oystercatchers (Haematopus ostralegus) and red knots (Calidris canutus) as well as seabirds such as northern fulmars (Fulmaris glacialis) and common scoters (Melanitta nigra).For most birds (n = 31) found dead along the shore no obvious cause of death was evident, while 17 individuals were killed by collisions with lighthouses.

Results

Overall, the nutritional status of the investigated birds was very poor, and the body mass in most cases was significantly lower compared to masses of living birds caught during the same periods of the year. This is partly linked to chronic parasitic or bacterial infections in different organs or to septicaemia. In some cases infections with zoonotic tuberculosis caused by Mycobacterium spp. were found. Avian influenza was not found in any of the collected birds.

Conclusion

The presented data contribute to the evaluation of the health status of birds in the German North Sea. Moreover, they present an important tool for the assessment of potential pathogens with an impact on the health status of seabirds and coastal birds.  相似文献   
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535.
Effect of nutrient intake on mammary gland growth in lactating sows   总被引:2,自引:0,他引:2  
Sixty-one primiparous sows were used to determine the response of mammary gland growth to different energy and protein intakes during lactation. After birth, litter size was set to 9 or 10 pigs. Sows were slaughtered at selected times up to 30 d of lactation. Individual sows were fed one of four diets that were combinations of different amounts of energy and protein (3.0 Mcal ME and 8.0 g lysine/kg diet; 3.0 Mcal ME and 16.2 g lysine/kg diet; 3.5 Mcal ME and 6.4 g lysine/kg diet; or 3.5 Mcal ME and 13.0 g lysine/kg diet). Mammary glands were collected at slaughter and trimmed of skin and the extraneous fat pad. Each gland was weighed, cut in half to measure cross-sectional area, ground, and stored at -20 degrees C for chemical analysis. Frozen, ground tissue was used to determine dry matter, dry fat-free tissue (DFFT), total tissue protein, ash, and DNA content. Only glands known to have been suckled were included in this data set. Response surface regression was used for statistical analysis. The percentage of protein, fat, ash, and DNA in each suckled mammary gland was affected only by total energy intake (P<.05). The percentage of dry tissue and fat decreased as the total energy consumed during lactation increased, whereas the percentage of protein and DFFT increased as total energy intake increased. There were quadratic effects (P<.05) of both total energy and protein intake on wet weight, dry weight, protein amount, DFFT amount, and DNA amount of each suckled mammary gland during lactation. This study shows that mammary gland growth is affected by nutrient intake during lactation. The weight of suckled mammary glands and the amount of mammary tissue protein, DFFT, and total DNA were maximal on d 27.5 of lactation when sows had consumed an average of 16.9 Mcal of ME and 55 g of lysine per day during lactation. Provision of adequate amounts of nutrients to sows during lactation is important for achieving maximal growth of mammary glands and maximal milk production.  相似文献   
536.
Epidural spinal myelolipoma was diagnosed in an 11.5-year-old castrated male Husky-cross that was evaluated at the veterinary teaching hospital due to progressive thoracolumbar spinal hyperaesthesia and mild proprioceptive pelvic limb ataxia. A focal, ill-defined mildly inhomogenous extradural mass lesion was detected by MRI. The dog was euthanized. At necropsy an extradurally located reddish mass of about 2.5 cm in diameter was present in the vertebral canal. The mass was identified histopathologically as an epidural myelolipoma.  相似文献   
537.
An experiment was conducted with the objective of measuring the concentrations of total milk solids (TMS), CP, and 5'monophosphate nucleotides in sow colostrum and milk. Twelve multiparous sows (Landrace x Yorkshire x Duroc) were used. Litter size was standardized at 11 piglets for all sows at farrowing. Sows were fed an 18.45% CP corn-soybean meal-based diet throughout lactation. The experimental period was the initial 28 d of lactation, with colostrum collected within 12 h of farrowing and milk collected on d 3, 7, 14, 21, and 28. Colostrum and milk samples were analyzed for TMS, CP, adenosine 5'monophosphate (5'AMP), cytidine 5'monophosphate (5'CMP), guanosine 5'monophosphate (5'GMP), inosine 5'monophosphate (5'IMP), and uridine 5'monophosphate (5'UMP). Total milk solids decreased (P < 0.05) from 26.7% on d 0 to 23.1% on d 3. The TMS further decreased (P < 0.05) to 19.3% on d 7, but remained relatively constant thereafter at 18.2, 18.8, and 19.2% on d 14, 21, and 28, respectively. The concentration of CP decreased from 16.6% in colostrum to 7.7, 6.2, 5.5, 5.7, and 6.3% in milk collected on d 3, 7, 14, 21, and 28, respectively (linear and quadratic effect; P < 0.05). Concentrations of 5'AMP, 5'CMP, 5'GMP, and 5'IMP increased from d 0 to d 3 and d 7, and then decreased during the remaining lactation period (quadratic effect; P < 0.05). The concentration of 5'UMP decreased from d 0 to 28 of lactation (linear and quadratic effects; P < 0.05). In colostrum, 5'UMP represented 98% of all 5'monophosphate nucleotides, and in milk, 5'UMP accounted for 86 to 90% of all nucleotides, regardless of day of lactation. The results of this experiment suggest that the concentrations of TMS and CP in sow mammary secretions changed during the first week of lactation, but were constant thereafter. Likewise, the concentrations of 5'monophosphate nucleotides changed during the initial week postpartum, but during the last 2 wk of a 4-wk lactation period, the concentrations were constant.  相似文献   
538.
Administration of triiodothyronine (liothyronine, 15 micrograms, q 8 h, for 6 treatments) caused marked decrease in serum concentration of thyroxine (T4) and estimates of free T4 (fT4) concentration in clinically normal cats. A prospective clinical study was done to evaluate the use of this suppression test for diagnosis of hyperthyroidism in cats with clinical signs suggestive of the disease, but lacking high serum concentration of iodothyronines. Twenty-three cats were confirmed as hyperthyroid on the basis of histologic changes in the thyroid gland or clinical improvement in response to administration of methimazole. Mean +/- SD serum concentration of T4 (34.3 +/- 12.7 to 31.3 +/- 11.5 nmol/L) and estimate of fT4 concentration (26.6 +/- 6.4 to 25.6 +/- 6.9 pmol/L) did not change after administration of liothyronine to these cats. Twenty-three cats were classified as nonhyperthyroid by histologic confirmation of other disease, abnormal results of other diagnostic tests that strongly supported primary disease other than hyperthyroidism, or spontaneous remission of weight loss without treatment. Mean +/- SD serum concentration of T4 (27.9 +/- 10.3 to 11.7 +/- 6.4 nmol/L) and estimate of fT4 concentration (21.7 +/- 5.4 to 10.4 +/- 4.4 pmol/L) decreased significantly (P less than 0.001) in response to administration of liothyronine. Discriminant analysis was used to identify variables from iodothyronine assays (eg, absolute concentration of T4 or absolute estimate of fT4 concentration, or changes of T4 or fT4 concentration) that provided the best diagnostic sensitivity and specificity.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
539.
540.
Extracts of the blue-green alga Oscillatoria agardhii were tested for acute toxicity on laboratory mice and rats. Material originating from lake Gjersjøen proved to be toxic to the animals, samples from the nearby lake Årungen did not. Clinical symptoms culminated in the development of a fatal shock due to decrease in circulating blood volume. Pathological examination revealed heavy pooling of blood in the liver and severe damage to the organ. Blood analyses also indicated liver damage. Effects were the same with extracts from a laboratory clone culture as from a natural water bloom, but the toxin content was higher in the bloom material. Toxicity was not affected by heat, acid or alkali treatment.  相似文献   
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