Assessment of electrocardiographic parameters in healthy dogs undergoing dobutamine stress testing

The electrocardiographic effects of dobutamine stress testing (10 to 40 microg/kg/minute) were investigated in five conscious healthy dogs. We studied the changes in the duration and amplitude of P wave, PR interval, duration of QRS complex, R wave amplitude, QT interval, and heart rate. Development of arrhythmias and ST segment abnormalities were also recorded. It was observed that dobutamine significantly affects atrioventricular-nodal conduction and total electrical systole time at higher infusion rates. Only a single episode of sustained ventricular tachycardia was observed, which was promptly restored to sinus rhythm shortly after dobutamine infusion was discontinued. No ST segment abnormalities were detected. Dobutamine stress testing was concluded to play a role in some ECG parameters at higher infusion rates.     

Analysis of the 96 most often cited articles published in veterinary journals in 2002 and 2003

The study concerned 123 Journals of the category "Veterinary Sciences" as defined in the Journal Citation Reports (Institute for Scientific Information (ISI), Philadelphia, USA). Using Web of Knowledge (ISI, USA), update December 3, 2005, articles published in 2002 and 2003 and cited 20 times or more were selected. The total number of selected articles was 96. They were published in 34 out of the 123 journals. Based on the country of the first author, the articles originated form 24 countries. Forty-nine of the 96 articles (51%) were written in only two countries being England (15) and the USA (34). The articles could be classified in six categories being immunology (21), microbiology and directly related subjects (48), prions and prion-induced diseases (5), reproduction (23), toxicology (3), and miscellanea (11). The category "microbiology" (48) was divided into six subcategories: general (1), bacteriology (17), mycology (3), parasitology (5), protozoology (6), and virology (5). Some articles were classified in more than one (sub)category.     

Influence of diet composition on intestinal volatile fatty acid and nutrient absorption in unanesthetized pigs

Two experiments were conducted to study the effect of the amount and nature of fiber and carbohydrates on nutrient and VFA absorption. Five Large White pigs in each crossover experiment were accustomed to a semisynthetic 14% protein diet containing 6 (LC) or 16% (HC) pure cellulose (Exp. 1) or 22% alfalfa meal (6.3% cellulose, HA) and 22% lactose and 6% pure cellulose (HL; Exp. 2). Each animal was then fitted with catheters in the portal vein and carotid artery and with a flow probe around the portal vein. Eight days after surgery, the absorption of reducing sugars (RS) and amino-N was studied for 12 h and that of VFA for 24 h after intake of a single 800-g meal. The alternate diet was then given for 7 to 10 d and a second series of samplings was performed within the same conditions. In the first experiment, added dietary cellulose decreased efficiency of absorption of RS (LC: 90.4 +/- 7.0%; HC: 81.6 +/- 3.6%) and amino-N (LC: 95.3 +/- 9.1%; HC: 70.3 +/- 2.8%; P less than .05). Daily absorption (24 h) of VFA tended to be larger when the cellulose level rose (LC: 1,184 +/- 85 mmol; HC: 1,429 +/- 216 mmol, NS) and increased (P less than .05) with the length of adaptation (21 to 28 d) to the diet, regardless of cellulose level. In the second experiment, after intake of the alfalfa diet, absorption of RS was high (97.8%), whereas absorption of amino-N (74.3%) and VFA (880 +/- 87 mmol/24 h) were low. Intake of lactose reduced absorption of RS (85.2%), did not alter absorption of N (75.9%) and increased absorption of VFA (1,181 +/- 218 mmol/24 h). Thus, the energy efficiency of the diet was lowered (P less than .05) when cellulose was added to the diet but not when alfalfa meal or lactose were added.     

Comparison of renal biopsy techniques in dogs

To evaluate adequacy of biopsy specimens obtained and safety to the patient, the standard keyhole biopsy technique (using digital immobilization of the right kidney and placement of the biopsy needle up to the capsule before obtaining a tissue sample) was compared with 9 technical modifications. Adequacy was judged by the number of intact glomeruli observed in the specimen. Detection of transected blood vessels and renal pelvis was presumed to have predictive value for postbiopsy complications of hemorrhage and hydronephrosis. Needle biopsy specimens were also obtained from left and right kidneys by use of laparoscopic visualization and were compared with those obtained by use of the standard keyhole technique. Although the standard keyhole technique yielded the highest percentage of adequate biopsy specimens, there was no statistical difference between specimens obtained by this technique and those obtained by the modified technique or by laparoscope-guided biopsy. Also, significant difference in percentage of biopsy specimens with renal pelvis was not found between specimens obtained by the standard and modified techniques. For each technique, the biopsy core length was measured and the mean value was calculated. In this study, core length did not correlate with adequacy of the biopsy specimen.     

Effects of additional feed during late gestation on reproductive performance of sows: a cooperative study

A cooperative research study involving 1,080 litters was conducted at eight stations to determine the effects of additional feed during the last 23 d of gestation on reproductive performance of sows and on preweaning performance of their pigs. Primiparous and multiparous sows were fed fortified corn- or sorghum-soybean meal diets (14% crude protein). Control sows received 1.82 kg/d from March through November and 2.27 kg/d from December through February. Treated sows were fed an additional 1.36 kg of feed/d from d 90 of gestation to farrowing. Sows were allowed to consume the same diet ad libitum during a 21-d lactation. Additional feed in late gestation resulted in greater (P less than .001) sow weight gain from d 90 to d 110 of gestation (16.8 vs 9.0 kg) and greater (P less than .001) parturition-lactation weight loss (21.3 vs 16.4 kg). Total weight gain from breeding to 21 d of lactation favored sows that received extra feed (27.5 vs 22.7 kg; P less than .001). Sows receiving extra feed had more live pigs at farrowing (10.05 vs 9.71, P = .06) and at 21 d postpartum (8.35 vs 8.06, P = .09), and the pigs were heavier at birth (1.48 vs 1.44 kg, P = .003) and at 21 d (5.37 vs 5.20 kg, P = .006). Lactation feed intake and number of days from weaning to estrus were not affected by treatment. The results indicate that additional feed in late gestation improves reproductive performance in sows. In this study, the cost of an additional 31 kg of feed/sow was more than offset by the value of the additional sow weight gain (approximately 5 kg), the additional .3 of a pig/litter at weaning and the additional 2.6 kg of total litter weaning weight.     

Immune function in dairy cows related to energy balance and metabolic status in early lactation

Two feeding experiments were carried out in 2 successive years with 28 cows of the Norwegian Red Cattle (NRF) in each experiment. The cows were randomly distributed into 4 groups and subjected to different feeding regimens from 1 month prior to calving until 12 weeks after calving. The experimental design was factorial (2 x 2) with respect to protein content of the concentrate (17.5% digestible crude protein (DCP) v.s. 12.5% DCP) and concentrate allowances (standard v.s. substandard allowances after calving). Silage was offered ad libitum. Samples for estimation of serum immunoglobulin-G, white blood cells and lymphocyte responses to the mitogens phytohemagglutinin, concanavalin A and pokeweed mitogen were collected 4 weeks prior to expected calving, and 2, 4 and 8 weeks after calving. The levels of milk immunoglobulin-G were estimated at calving and 2, 4 and 8 weeks after calving. A significant positive relationship was found between the estimated energy balance and the lymphocyte response to mitogens. Little evidence was found for the existence of a significant relationship between the immunologic parameters and plasma indicators of metabolic status. The lymphocyte response to phytohemagglutinin and levels of serum immunoglobulin-G increased, while levels of milk immunoglobulin-G decreased during the period from calving to 8 weeks after calving. Increased milk somatic cell counts were associated with a significant decrease in the lymphocyte responses to mitogens.     

Effect of lenperone hydrochloride on gastroesophageal sphincter pressure in healthy dogs.

Treatment of healthy dogs with the butyrophenone derivative, lenperone hydrochloride, at two different doses significantly decreased gastroesophageal sphincter pressure (GESP). No dose-related effect was identified. Individual variation in the response to lenperone hydrochloride was noted which was consistent on a day-to-day basis. Lenperone hydrochloride is unsuitable for chemical restraint of dogs undergoing esophageal manometry because it decreases GESP and because the magnitude of the decrease varies considerably between dogs.     

Nutrition and the heart

Nutritional deficiencies (e.g., carnitine in dogs, taurine in cats) resulting in cardiomyopathy, and nutritional excesses (e.g., calories leading to obesity, sodium leading to hypertension) have emerged as important considerations in cardiology. These dietary factors may become particularly exaggerated in altered physiological and/or pathological states (e.g., pregnancy, old age, primary cardiovascular disease). Unfortunately, we do not have complete information on requirements for essential nutrients, nor do we know the precise role nutrition may play in the production of so-called old-age diseases or on the interactions among other organ systems (e.g., kidney, liver) and the heart.