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21.
A total of 36 goats of the breeds Gemsfarbige Gebirgsziege (G), Saanen (S) and Toggenburger (T) were exposed for periods of 4 hours to the following climatic conditions: normal (20°C, 50% RH); cold (?5°C); heat (40°C, 30% RH) and high altitude (4000 m, 20°C, 50% RH).In the cold the animals were just able to maintain normal core temperature. Skin temperatures on the flank decreased by 3–5°C, those on the ear and the shank by 20–21°C. Respiratory rate and blood-pH decreased. The elevation in heart rate (18 beats/min) and cold shivering were indicative of a rise in heat production.In the heat, rectal temperature increased but attained a plateau at 40.7°C. Respiratory rate rose from 26 to 261 breaths/min, producing a slight respiratory alcolosis with a rise in blood-pH of 0.036 units. Heart rate augmented by 15 beats/min.At high altitude rectal temperature declined by 0.2°C, which was attributed to the quiet behaviour of the goats. There were increases in haemoglobin (+0.83 g/100 ml), haematocrit (+2.5 vol.%), erythrocyte number (+0.78 mill./mm3) and specific gravity of the blood (+0.002). The increases were considered to reflect discharge of blood from reservoirs, since they occurred within 4 hours. A rise in pH, unaccompanied by a rise in respiratory rate, pointed to an increase in tidal volume.There were suggestions of breed differences. The T-breed appeared to be relatively cold tolerant owing to the high thermal insulation of their hair coat, and also relatively heat tolerant, possibly due to their low heat production, as evidenced indirectly by their low normal heart rate (87 compared with 95 beats/min in the other two breeds). 相似文献
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Khalid A. ABDOUN Emad M. SAMARA Aly B. OKAB Ahmed A. AL‐HAIDARY 《Animal Science Journal》2012,83(7):556-561
It was the aim of this study to investigate the regional variations in surface temperature and sweating rate and to visualize body thermal windows responsible for the dissipation of excess body heat in dromedary camels. This study was conducted on five dromedary camels with mean body weight of 450 ± 20.5 kg and 2 years of age. Sweating rate, skin and body surface temperature showed significant (P < 0.001) circadian variation together with the variation in ambient temperature. However, daily mean values of sweating rate, skin and body surface temperature measured on seven regions of the camel body did not significantly differ. The variation in body surface temperature compared to the variation in skin temperature was higher in the hump compared to the axillary and flank regions, indicating the significance of camel's fur in protecting the skin from daily variation in ambient temperature. Infrared thermography revealed that flank and axillary regions had lower thermal gradients at higher ambient temperature (Ta) and higher thermal gradients at lower Ta, which might indicate the working of flank and axillary regions as thermal windows dissipating heat during the night. Sweating rate showed moderate correlation to skin and body surface temperatures, which might indicate their working as potential thermal drivers of sweating in camels. 相似文献
24.
AL Ridler 《New Zealand veterinary journal》2013,61(6):270-273
Sheep farming in New Zealand is based on an outdoor grazing system with various systems of grazing management utilised depending on the type of farm and the time of year. In the current grazing systems, periods of high stocking density, sometimes combined with poor husbandry, contribute to infectious diseases such as abortion and salmonellosis. Intensification such as housing or intensive stocking of ewes for lambing, or feedlot systems, are unlikely to become common in sheep production in New Zealand. However, should these be utilised on individual farms there is likely to be in an increase in diseases such as coccidiosis, bacterial diseases of lambs, cryptosporidiosis and mastitis. In any management system involving high stocking densities, careful husbandry is essential to minimise the transmission of infectious diseases. 相似文献
25.
AIM: To develop a technique to estimate the volume of epithelial lining fluid (ELF) obtained during bronchoalveolar lavage (BAL) and pleural lavage (PL) in the dog, using the urea dilution method. METHODS: BAL and PL fluids were obtained by saline lavage of pulmonary and pleural cavities of nine clinically healthy mixed-breed dogs immediately after euthanasia. Cell counts in the BAL and PL fluids were measured using standard techniques. The concentration of ELF in each lavage fluid was calculated from the relative concentration of urea in plasma and in each type of lavage fluid. Cell counts in ELF were then calculated. RESULTS: There were substantially higher cell counts in ELF compared to BAL or PF fluid. However, nucleated cell counts in ELF could not be predicted from cell counts in BAL or PL fluid. CONCLUSIONS AND CLINICAL RELEVANCE: These results suggest that accurate assessment of cellular or non-cellular components in lavage fluids should include a calculation of the proportion of ELF recovered, using a method such as urea dilution. 相似文献
26.
Uterus didelphys is a rare congenital abnormality of the reproductive tract. Although it occurs in various species, there are no published reports describing pregnancy outcome in association with this abnormality. Herein we describe a case of successful unilateral singleton pregnancy in a ewe incidentally found to have uterus didelphys during the course of a biomedical research study. The pregnancy was established using assisted reproductive techniques and interrupted in late gestation, at which point the abnormality was identified. Serial ultrasound assessment of foetal biometry revealed a normal foetal growth trajectory. Despite a 45% reduction in placentome number, total placentome weight was near normal secondary to compensatory placentome growth and development. To our knowledge, this is the first detailed report of normal foetal growth in an animal with uterus didelphys and illustrates the ability of the ovine placenta to adapt to a reduced number of placentomes and maintain foetal nutrient supply. 相似文献
27.
Steinberg TA Boettcher IC Matiasek K Hirschvogel K Hartmann K Kunz A Kuntz A Fischer A 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2008,37(2):207-216
BACKGROUND: Inflammation of the central nervous system (CNS) is a frequent condition in cats but etiology often remains unsolved. Routine cerebrospinal fluid (CSF) analysis can be extended through the calculation of the albumin quotient (Q(alb)), a marker of the integrity of the blood-brain barrier (BBB), and IgG index, an estimate of intrathecal IgG synthesis. OBJECTIVES: The purpose of this study was to validate nephelometric methods for CSF protein analysis, and to use the Q(alb) and IgG index to discriminate blood- and brain-derived immunoglobulin fractions in cats with feline infectious peritonitis (FIP). METHODS: Cats presented to our clinic between 2001 and 2005 were included in the study based on clinical and laboratory data and histopathologic findings at necropsy. Cats were grouped as having nonneurologic disease (controls; n=37), brain tumors (n=8), FIP involving the CNS (n=12), and extraneural FIP (n=12). CSF-total protein (TP) was measured and albumin and IgG concentrations were measured in paired CSF/serum samples; Q(alb) and IgG index were calculated. Intraassay and interassay precision of the nephelometric assays were determined using pooled samples. RESULTS: Coefficients of variation for the nephelometric assays ranged from 2.7% to 7.2%. In control cats, CSF-TP concentration ranged from 0.06 to 0.36 g/L, Q(alb) ranged from 0.6 to 5.7 x 10(-3), and IgG index ranged from 0.3 to 0.6. Q(alb) and IgG index were significantly higher in cats with brain tumors and cats with CNS-FIP compared with other groups. Compared with control cats, pleocytosis was evident in 8 of 12 (67%) cats and CSF-TP was increased in 3 of 12 (25%) cats with CNS-FIP. CONCLUSION: Nephelometry is a reliable method for measurement of CSF protein, albumin, and IgG in cats. The Q(alb) and IgG index did not identify a CSF protein pattern specific for BBB dysfunction or intrathecal IgG synthesis in cats with CNS-FIP. 相似文献
28.
Pakeza Drkenda Osman Musić Slađana Marić Darko Jevremović Sanja Radičević Metka Hudina Sabina Hodžić Achim Kunz Michael M. Blanke 《Erwerbs-Obstbau》2018,60(4):295-304
The objective of the joint project between the two universities of Bonn and Sarajevo was to study the effects of climate change associated with warmer winter and spring temperatures on fruit tree phenology. Changes in flowering date of apple and cherry were correlated with local weather data obtained concomitantly on-site at four locations in the Balkan countries Slovenia, Serbia, B & H and at Bonn, Germany.Phenological data of flower opening (F1; BBCH 61) of apple cv. ‘Golden Delicious’ originated from 55 years at Cacak (44?°N, Serbia) and at Klein-Altendorf, University of Bonn (50?°N), cv. ‘Bobovec’ from the University of Ljubljana (46?°N, Slovenia) and cherry cv. ‘Burlat’ (35 years at Klein-Altendorf, 50?°N) and 20–30 years at Tuzla (44?°N, B & H) and Mostar (43?°N, Bosnia & Herzegovina; B & H).The annual precipitation showed a negligible change in the last 55 years of ±5% in the Balkan countries (e.?g. Cacak, 699?mm), but only ±1.8% at Klein-Altendorf (605?mm) with a slight shift to more winter rainfall.Regression analysis showed an increase in mean temperature of 1.7?°C (annual) and 1.45?°C for the vegetation period at Klein-Altendorf (last 55 years), Germany. In the evaluated Balkan stations, the greatest increase in annual air temperature between two climate phases (until 1987 versus from 1988 until now) was at Ljubljana (1.4?°C) and Cacak (1.2?°C) in contrast to the least increase (0.3?°C) at Tuzla (annual average 10?°C) and an intermediate value (0.9?°C) in the warmer Mostar (annual average 14.5?°C).This recent temperature increase advanced flower opening by 10–14 days for apple such as cv. ‘Golden Delicious’ at Cacak and 7–10 days (last 55 years) at Bonn and 4–5 days (last 35 years) for the early cherry cv. ‘Burlat’ at Klein-Altendorf/Bonn; at Mostar and Tuzla, the effect of climate change was greater with the early cherry cv. ‘Burlat’ (26 days) compared with the difference of the late cherry cultivar (16 days). Before recent climate change (1973–1987), cherry flower was advanced by 10 days in the warmer med climate at Mostar but delayed by 16 days in the cooler Tuzla. The results, i.?e. the flower advancement in the Continental climate but flower delay in the med climate, are discussed with respect to the risk of late frost and countermeasures to combat climate change effects. 相似文献
29.
PC Sereno AL Beck DB Dutheil B Gado HCE Larsson GH Lyon JD Marcot OWM Rauhut RW Sadleir CA Sidor DD Varricchio GP Wilson JA Wilson 《Science (New York, N.Y.)》1998,282(5392):1298-1302
Fossils discovered in Lower Cretaceous (Aptian) rocks in the Tenere Desert of central Niger provide new information about spinosaurids, a peculiar group of piscivorous theropod dinosaurs. The remains, which represent a new genus and species, reveal the extreme elongation and transverse compression of the spinosaurid snout. The postcranial bones include blade-shaped vertebral spines that form a low sail over the hips. Phylogenetic analysis suggests that the enlarged thumb claw and robust forelimb evolved during the Jurassic, before the elongated snout and other fish-eating adaptations in the skull. The close phylogenetic relationship between the new African spinosaurid and Baryonyx from Europe provides evidence of dispersal across the Tethys seaway during the Early Cretaceous. 相似文献
30.