The effect of intravenous administration of variable-dose midazolam after fixed-dose ketamine in healthy awake cats

The effects of intravenous administration of variable-dose midazolam and ketamine (3 mg/kg) were studied in twelve healthy unmedicated cats from time of administration until full recovery. A range of midazolam doses (0.0, 0.05, 0.5, 1.0, 2.0 and 5.0 mg/kg) was chosen, so that beneficial and/or detrimental effects could be documented and the therapeutic window for further study determined. One minute after administration of ketamine, all cats had assumed a lateral position, mostly with head up. Muscle tone was increased (100%), apneustic breathing pattern evident in 92% of cats, chewing without stimulation of the oropharyngeal area was observed in most cats (97%), but most cats did not salivate (87%). At 2.5 min after completion of ketamine injection and 1 min after administration of saline, a similar picture was observed, except that salivation was evident. All cats chewed or swallowed in response to a finger or laryngoscope placed in the oropharyngeal area and, while most cats were not aware of a noxious stimulus to the tail, some cats were aware of a noxious stimulus to the paw. Recovery from ketamine alone was rapid and smooth with cats rolling into sternal recumbency and then cautiously walking with ataxia. Recovery to walking without incoordination was also rapid (< 2 h) and no abnormal behavioural patterns were observed during recovery. Administration of midazolam after ketamine, had beneficial effects and the therapeutic window for midazolam was found to lie between 0.05 mg/kg and 0.5 mg/kg. Administration of any dose of midazolam after ketamine caused a greater proportion of cats to assume a laterally recumbent position with head down compared with ketamine alone, however, the time period of recumbency was only significantly longer with a midazolam dose of 2.0 mg/kg or above. Doses of midazolam of 0.5 mg/kg or above decreased muscle rigidity but did not affect salivation or respiratory pattern observed in cats which received ketamine alone. A significantly greater proportion of cats which received ketamine and midazolam 0.5 mg/kg or above did not swallow in response to a finger or a laryngoscope placed in the mouth compared with that which received ketamine alone. The length of time in which cats did not swallow was only significantly longer at midazolam doses of 1.0 mg/kg and above. At midazolam doses of 0.5 mg/kg or above, the proportion of cats without a nociceptive response to a tail or paw clamp was significantly greater than cats which received ketamine alone. The time period without nociceptive response, however, was not influenced by midazolam administration. The time taken for cats which received ketamine and midazolam 0.05 mg/kg or 0.5 mg/kg to assume sternal position, walk with ataxia, walk without ataxia, behave normally when approached or restrained and recover normal arousal state was not significantly different from cats which received ketamine alone. Ketamine and midazolam 5.0 mg/kg significantly prolonged all recovery times compared with ketamine alone. Unfortunately, a greater proportion of cats which received ketamine and midazolam 0.5 or 5.0 mg/kg exhibited detrimental behavioural effects. These were more likely to be adverse and included restlessness, vocalization and difficulty approaching and restraining cats. In this study, an     

饲料颗粒：家禽生长不可忽视的基础

编者按:在家禽养殖中,饲料是支撑家禽生长的最基本元素.除去营养需要外,高度加工处理的饲料从一开始着眼于提高家禽的生产性能,以达到效率最优化.     

Circadian and ultradian rhythms of body temperature and peripheral concentrations of insulin and nitrogen in lactating dairy cows

To investigate possible circadian and ultradian periodicities for peripheral insulin and urea in lactating dairy cows, integrated 15-min blood samples were taken sequentially over 48 hr from six cows. In addition, radiotelemetry measurements of body temperature were averaged over the same 15-min periods. Cows were housed in an environmental chamber at 19 degrees C with lights on 0700 to 2300 hr; fed daily at 0900 hr; and milked at 0800 and 2000 hr. For five of the six cows, body temperature showed a circadian rhythm peaking at 2323 hr with an amplitude of 0.34 degree C. For the sixth cow, body temperature was 180 degrees out-of-phase, peaking at 1230 hr with an amplitude of 0.12 degree C. Circadian rhythms for insulin and urea were consistent for all six cows peaking at 1743 hr with an amplitude of 0.74 ng/ml for insulin and at 1034 hr with an amplitude of 3.83 mM for urea. Body temperature and insulin also displayed episodic increases that often exceeded the amplitudes of circadian rhythms. For body temperature, a broad increase in spectral power was seen for periods between 100 and 175 min; time intervals between peaks averaged around 100 min. For insulin, power spectra for individual cows universally indicated rhythms with periods of approximately 45 and 80 min; time intervals between peaks averaged approximately 65 min. For urea, almost all spectral energy was confined to the 24-hr rhythm, although there was evidence of a low-amplitude, 60-min rhythm. In conclusion, when animals are acclimated to a rigidly controlled environment and frequent blood sampling is accomplished with minimal intervention, it is possible to detect rhythms inherent in the regulation of metabolic variables.     

Blood metabolites and their relationship with production variables in dual-purpose cows in Venezuela

A survey was carried out on 79 lactating Bos taurus/indicus cross-bred cows on three dual-purpose cattle farms to measure the blood concentration of metabolites and to evaluate possible relationships with nutritional status and productive variables. A rotational grazing system on Star grass and other tropical pastures (10-12% CP in leaves) was used and 2-3 kg/cow/day of concentrate were fed on two farms. Restricted calf suckling was used in two herds. Average milk yield sold per farm was 6 kg/day/cow and body condition scores (BCS) were between 3.0 and 3.8 on a scale of one-to-five. On two farms, the average interval from calving to conception (ICC) was more than 145 days. Mean blood concentrations of albumin, globulin, urea, beta-hydroxybutyrate and phosphorus were generally within reference values, but a significant group of cows had low levels of albumin and urea and high levels of globulin. Packed cell volume (PCV) was below normal values, with anemia in 63% of cows during the second trimester of lactation, which was negatively correlated to milk yield. The high incidence of anemia could be related to factors such as hematophagic parasites, not evaluated in this study. ICC values were negatively related to albumin level and could be associated with protein deficiency in the diet or with disease, as globulin values were high in many cows. Based on these diagnoses, an experiment was carried out on one of the farms to evaluate the influence of supplementation with 0.5 kg/cow/day of fish meal. Total milk yield was not influenced by the fish meal and reproductive efficiency was high in the two supplemental treatments. It was shown that supplementation with undergraded protein is not required in these cows.     

Associations amongst three feline Porphyromonas species from the gingival margin of cats during periodontal health and disease

Digoxigenin labelled whole chromosomal DNA probes directed against three feline members of the genus Porphyromonas (P. gingivalis VPB 3492, P. circumdentaria NCTC 12469T and P. salivosa VPB 3313) were used to identify and quantify organisms in samples taken from the gingival margins of 40 domestic cats with different grades of periodontal disease. At the right upper canine tooth, the grade of periodontal disease ranged from 0 to 5 and the cfu of facultative/obligate anaerobes ranged from 5.5 x 10(4) to 2.0 x 10(6)). In 38 of the 40 cats, at least one of the three Porphyromonas species was isolated and regression analysis showed that the cfu of total Porphyromonas sp. was a highly significant indicator of the grade of periodontal disease (p < 0.001, R2 0.510). Feline P. gingivalis was isolated from 37 of the 40 cats and regression analysis showed that it was a highly significant predictor of the grade of periodontal disease (p < 0.001, R2 0.561). The cfu of P. salivosa was a significant predictor of the grade of periodontal disease (p < 0.001, R2 0.286) and regression analysis showed that there was a significant positive relationship between cfu of P. circumdentaria and grade of periodontal disease (p = 0.018, R2 0.116). The periodontal grades at the right upper third premolar tooth ranged from 0 to 6. The cfu of facultative/obligate anaerobes isolated ranged from 1.2 x 10(5) to 7.9 x 10(6), and regression analysis showed that cfu was a significant predictor of periodontal grade (p < 0.001, R2 0.378). The cfu of total Porphyromonas species ranged from 1.2 x 10(4) to 1.7 x 10(6) and regression analysis of the cfu against the grade of periodontal disease showed a highly significant association (p < 0.001, R2 0.633). The cfu of P. gingivalis ranged from 0 to 1.1 x 10(6) and regression analysis of the cfu of P. gingivalis against the grade of periodontal disease showed a highly significant association (p < 0.001, R2 0.439). The cfu of P. salivosa was a significant predictor of the grade of periodontal disease (p < 0.001, R2 0.479) and the same association was found between cfu of P. circumdentaria and grade of periodontal disease (p = 0.002, R2 0.204). This study has established Porphyromonas as anumerically significant and highly prevalent genus in feline periodontal disease.     

Heat processing changes the protein quality of canned cat foods as measured with a rat bioassay

The purpose of this study was to determine the influence of increasing heat treatment on the protein quality of a canned cat food. A standard recipe cat food was canned and heat-treated for different times in a standard laboratory autoclave to obtain experimental diets containing different lethality values. Estimates of the lethality value of the different diets were calculated using the temperature-time relationship recorded with a data logger positioned at the center of the can. The experimental diets were analyzed for crude protein, amino acids, and reactive lysine (fluorodinitrobenzene and O-methylisourea) and were used in a rat bioassay for the determination of the true ileal digestibility of amino acids. The heat treatment of the cat food resulted in experimental diets with lethality values of 5.3, 8.6, 17.2, and 24.3 min. There was no decrease in the amino acid content of diet with increasing heat treatment. The reactive lysine content of the diets also showed no change with heat treatment. There were significant (P < .05) changes in the true ileal digestibility of all amino acids and amino acid nitrogen, and the digestibility of most amino acids decreased with increasing heat treatment.     

Health and growth performance of barrows reared in all-in/all-out or continuous flow facilities with or without a chlortetracycline feed additive.

OBJECTIVE: To compare health and growth performance in barrows reared in all-in/all-out (AIAO) or continuous flow (CF) management systems. ANIMALS: 400 barrows. PROCEDURE: Barrows (approx 2 months old) were allotted to 4 replications (100 barrows each); barrows were housed in AIAO or CF rooms (10 pens/room), and 50 pigs/replicate received chlortetracycline (CTC, 110 mg/kg of feed). Barrows from each pen were slaughtered at 3, 4, 5, and 6 months old. RESULTS: Barrows in the AIAO room had greater total daily gain (TDG) and lean daily gain (LDG) than did barrows in the CF room. Addition of CTC did not improve TDG or LDG in either environment. Barrows in the AIAO room reached body weight of 104.5 kg in 169.7 days, compared with 177.3 days for barrows in the CF room. Feed-to-gain ratio was not affected by management or CTC. Lungs from barrows reared in AIAO facilities had a lower percentage of lesions than did lungs of barrows reared in CF facilities (1.74% vs 9.52%). Addition of CTC did not affect prevalence and extent of lung lesions. Extent of lung lesions was positively correlated with change in serum optical density (OD) to Mycoplasma hyopneumoniae (r = 0.35), but not with change in serum OD to Actinobacillus pleuropneumoniae. Lean growth and serum OD to M. hyopneumoniae and A. pleuropneumoniae were not correlated. CONCLUSIONS: Health and growth performance were better for barrows in an AIAO facility, compared with a CF facility, but addition of CTC to feed failed to enhance health or performance of barrows in either facility.     

Bone plate fixation of distal radius and ulna fractures in small- and miniature-breed dogs.

Bone plate fixation was reviewed in 29 distal radial fractures of small- and miniature-breed dogs. Twenty-two fractures in 18 dogs were available for follow-up. Number of complications and return to function were evaluated. Complications occurred in 54% of the fractures. Catastrophic complications occurred in 18% of fracture repairs with follow-up, while minor complications occurred in 36%. Sixteen (89%) of 18 dogs had a successful return to function. Bone plate fixation is a successful repair method for distal radius and ulna fractures in small-breed dogs, compared to previously reported methods.     

Vaginal position and length in the bitch: relationship to spaying and urinary incontinence

A study was undertaken to determine if the vagina might be a suitable site for the measurement of intra-abdominal pressure during cystometry in the bitch. The position of the cranial vagina and vaginal length were measured radiographically and the effects of spaying and urinary incontinence on these variables were evaluated in 30 continent and 30 incontinent bitches. The study used retrograde vaginourethrograms which had been obtained from animals used in a previous study. The cranial vagina was intra-abdominal on 36 of the vaginourethrograms, being least commonly intra-abdominal in incontinent bitches (11/30). Vaginal position was related linearly to vaginal length and continence status (P < 0.01), while its length was related to bodyweight (P < 0.01). Allowing for bodyweight, neutered animals had significantly shorter vaginas than entire bitches (P < 0.01). Measurement of intra-abdominal pressure with concomitant measurement of intravesical pressure is essential if accurate assessment of detrusor pressure is to be determined during cystometry. The vagina is unlikely to be a useful location from which to measure intra-abdominal pressure since any pressure-measuring catheter inserted into it may fall outside the abdominal pressure zone. This is particularly true of neutered and/or incontinent bitches, the groups in which urodynamic investigations of urinary incontinence are most frequently indicated.