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81.
A 7-month-old female Poodle was evaluated for a sound continuously emanating from its left ear. The frequency and intensity of the tone was matched by use of a multifrequency audiometer. The frequency and intensity of the sound were 9,594 Hz and 45.5 decibels sound pressure level, respectively. On the bases of normal brain stem auditory-evoked responses and behavioral response to sound, the dog was believed to have normal hearing in both ears. Emission of sound from an ear, referred to as an otoacoustic emission, is a condition that has been reported in human beings and small animals. Successful treatment in human patients with drugs and masking sounds is difficult, and treatment has not been reported in animals. This condition in dogs is not considered life-threatening.  相似文献   
82.
The possible involvement of the pituitary-adrenocortical axis with severe pre- and post partum udder oedema was studied in a herd of 60 Holstein/Friesian cows. The prevalence of udder oedema in this herd was about 75 per cent. The animals were fed a diet containing high levels of potassium (average daily potassium intake 410 g per cow). The concentrations of sodium, potassium, chloride and total protein in the plasma of the cows were within their normal ranges. In one animal a very low plasma cortisol concentration (2.30 ng/ml) was accompanied by normal plasma glucose and beta-hydroxybutyrate concentrations. The adrenal responsiveness of two heifers with severe udder oedema was impaired one month after parturition in comparison with 11 normal animals (increases from 3.27 to 38.8 and 23.2 to 37.8 ng cortisol/ml compared with 8.02 +/- 1.19 to 146 +/- 16.7 ng cortisol/ml but returned to normal spontaneously after 175 days. One cow was diagnosed as having primary adrenocortical insufficiency.  相似文献   
83.
Central diabetes insipidus was diagnosed by vasopressin measurements during hypertonic stimulation in a 9-year-old male giant Schnauzer with polyuria and polydipsia. The impaired release of vasopressin was believed to be caused by a large pituitary tumor, which was visualized by computed tomography. Studies of the function of the anterior lobe and the pars intermedia of the pituitary gland were conducted, and high concentrations of ACTH and α-melanotrophic hormone (α-MSH) were found without concomitant hyperadrenocorticism. Studies of the molecular size of the immunoreactive ACTH in plasma by gel filtration revealed that most of the circulating immunoreactivity was not ACTH but its precursor pro-opiomelanocortin (POMC) and low-molecular-weight POMC-derived peptides. The pituitary tumor of this dog probably originated from melanotrophic cells of the pars intermedia. The sensitivity of the pituitary-adrenocortical system for the suppressive effect of dexamethasone was unaffected.  相似文献   
84.
Eight hours fasting in Yorkshire terrier pups resulted in marked variation of blood glucose, showing both hypo- en hyperglycaemia. Prolonged fasting in three Yorkshire terrier pups resulted in hypoglycaemia with concomitant ketosis and steatosis of the liver. The hypoglycaemia was associated with decreasing insulin and increasing glucagon and cortisol levels. This is in contrast to fasting adult dogs, which maintain glucohomeostasis and show only slightly decreased insulin levels, normal glucagon levels and a moderate increase of plasma ketone bodies. The reaction to an eight hour fasting period in the Yorkshire terrier pups is thought to be related to inadequate gluconeogenesis and diminished insulin production and/or release. The different reaction to prolonged fasting, compared to adult dogs and pups of larger breeds, seems related to inadequate gluconeogenesis and results in hypoglycaemia, a ketogenic hormonal setting and steatosis of the liver. Frequent feeding of a high-energy, protein-rich diet to both mother and pups may prevent toy-breed pups from developing hypoglycaemia and may help them to overcome periods with a decreased intake of energy.  相似文献   
85.
The occurrence and incidence of pneumonia in housed calves were not related to the selenium status of the herd as measured by blood glutathione peroxidase activity nor were they affected by selenium treatment of calves during the neonatal period. Pneumonia was related more closely to herd size and building design.  相似文献   
86.
The recent identification of maedi-visna virus infection in three commercial flocks of indigenous sheep in Britain is described. In one flock the evidence suggested that overt clinical disease was present. The implications of the findings are discussed.  相似文献   
87.
The alkyl phenyl ketone oxime O-benzyl ethers are a new group of insecticidal compounds. Although they lack the ester linkage, they resemble the pyrethroids in general, and the esters of 2-phenylalkanoic acids, in particular fenvalerate, because they show similar physiological effects on isolated nerve preparations and on whole insects; they also show a similar pattern of change of biological activity in response to structural change. The compounds may exist as two geometric isomers, of which only the (E) series shows significant biological activity; this observation appears to have some bearing on the relationship between conformation and activity in the pyrethroid series as a whole.  相似文献   
88.
89.
The association of herd characteristics and intervention strategies with time under quarantine was evaluated for 163 farrow-to-finish swine herds enrolled in the voluntary phase (1986–1987) of the pseudorabies virus (PRV) eradication program in the state of Illinois (USA). Vaccination was the intervention strategy used most widely (69% of herds), particularly in larger herds. Depopulation was used primarily when PRV seroprevalence was high, and test-and-removal when seroprevalence was low. Approximately 50% of the herds were released from quarantine within 3 years of developing a herd clean-up plan.

Multiple regression analysis using the Cox proportional hazards model indicated the following. Vaccination had a strong association with a longer time until release from quarantine (P<0.001). This is attributed to the lack of a vaccine differential test during this time, which made diagnosis of natural infection more difficult. Offspring segragation was associated with a longer time under quarantine (all herds: P=0.05; non-vaccinated herds: P=0.004). Delay in implementation of a herd clean-up plan was also associated with longer time under quarantine (all herds: P=0.012; non-vaccinated herds: P<0.001). Herds with higher seroprevalence at the time of agreement to a herd plan required a longer time under quarantine (all herds: P<0.001). This result was apparent for non-vaccinated herds (P=0.001), and thus is not merely a consequence of vaccination. Herds in areas with a high geographic density of quarantined herds required a longer time before release from quarantine (all herds: P=0.003), although this trend was not apparent for non-vaccinated herds (P=0.39). After taking PRV seroprevalence into account, there was no apparent association of time under quarantine with sow herd size (all herds: P=0.057; non-vaccinated herds: P=0.81) or confinement housing (all herds: P=0.19; non-vaccinated herds: P=0.91).  相似文献   

90.
The effect of early nutrition on subsequent bone development was studied using gilts that had previously been fed ad libitum or 75% ad libitum intake and 100 or 150% National Research Council-recommended daily Ca and P from weaning to 100 kg. During the three-parity reproductive study, sows were fed a 14% protein diet. Metacarpals and metatarsals were taken from sows culled due to lameness or failure to breed and from sows after completing three parities. Femur and humerus articular cartilage and turbinates were described at necropsy. Metacarpals and metatarsals were heavier and tended to have thicker walls when sows were previously fed ad libitum or fed 150% Ca and P. Energy intake produced the greater response. Metacarpal breaking strength was greatest for sows previously fed ad libitum. Metatarsals were not affected by energy intake. Stiffness, Young's modulus of elasticity (YME) and flexural modulus for metacarpals and metatarsals were not affected by energy intake. Previously fed Ca and P intakes did not affect any of the mechanical bone characteristics. Metacarpals were heavier, had a greater breaking strength, were more elastic and exhibited slightly less resistance to bending than the metatarsals. The ether extract, ash, Ca and P content and the Ca:P ratio of metacarpals and metatarsals were not affected by previously fed energy or Ca and P intakes. The ether extract content tended to decrease and the ash, Ca and P content tended to increase with age. Articular cartilage and turbinate scores were not influenced by previously fed energy or Ca and P intakes. The YME and flexural modulus were the only bone characteristics that were even poorly correlated (average r = .25) with soundness scores, suggesting that high values result in poorer soundness scores. Energy and Ca and P intakes during growth and development had only minimal effects on bone characteristics and no apparent effect on structural soundness and longevity of sows kept for three parities.  相似文献   
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