Energy metabolism in canine erythrocytes associated with inherited high Na+- and K+-stimulated adenosine triphosphatase activity

Energy metabolism in canine erythrocytes associated with inherited high Na+- and K+-stimulated adenosine triphosphatase [(Na,K)-ATPase] activity (HK cells) was compared with that in normal canine erythrocytes (LK cells). Activities of some of the glycolytic enzymes in the HK cells were significantly higher than those in LK cells. The concentrations of adenosine triphosphate (ATP) and glycolytic intermediates in HK cells were almost equal to those in LK cells. Glucose utilization and lactate production by HK cells in vitro and incorporation of [32P]orthophosphate or [14C]glucose into 2,3-diphosphoglycerate in HK cells were higher than in LK cells. Radioactivity of [32P]ATP in HK cells was lower than in LK cells, but increased to approximately that of LK cells when (Na,K)-ATPase of HK cells was completely blocked by ouabain. When HK cells and LK cells were incubated in the absence of glucose, the concentration of ATP in HK cells was decreased more than that of LK cells. Although ouabain reduced the rate of decrease in ATP in HK cells, the decrease in ATP in HK cells was still 2-fold that in LK cells. The half-life of HK cells was about one-half that of LK cells. The results indicated that glycolysis is greater in HK cells than in LK cells, and that the increased glycolysis in HK cells was stimulated by an increased rate of ATP breakdown for active cation transport by the (Na,K)-ATPase and by increased degradation of ATP for some other pathway, eg, glutathione synthesis. Thus, the increased demand for ATP in HK cells might result in shortening the lifespan of HK erythrocytes.     

Effect of ranitidine on gastric acid secretion in young male horses

Gastric cannulas were placed surgically in 5 young male horses. After a 2-week recovery period, horses were studied once a week. Horses were fasted for 24 hours, and gastric fluid output was collected for 5 continuous hours. Volumes were recorded every 15 minutes, and pH and hydrogen ion concentration were determined in an aliquot from each period. In 10 basal experiments, using 5 horses, volume, pH, and hydrogen ion concentration were continuously variable. Mean acid output was 45.1 +/- 2.02 microEq/15 min/kg (mean +/- SEM). In 6 experiments, using 3 horses, 0.5 mg of ranitidine/kg of body weight, given as an IV bolus after a 1-hour basal collection, significantly (P less than 0.02) inhibited hourly total acid output for 4 hours, but did not significantly change pH. The cannulation technique was done without complications, and horses tolerated the cannula for several months. Seemingly, the horse has a continuously variable gastric acid secretion, and histamine type-2 receptors have a role in this process.     

Clinical,histological and immunophenotypic findings in a mare with a mammary lymphoma associated with anaemia and pruritus

An 18‐year‐old Quarter Horse mare presented with an 18 week history of dermatological lesions characterised by recurrent urticaria and recent signs of enlarged mammary glands, pyrexia, alopecia and intense pruritus. Haematological and serum biochemical analyses revealed anaemia, leucocytosis, thrombocytopenia and hyperfibrinogenaemia. Mammary discharge was evaluated and revealed neutrophilia. Cytological examinations of fine needle aspirates from the parotid lymph nodes were normal. Common causes of anaemia were ruled out by specific tests. The initial diagnosis was mastitis and 2 weeks later the animal returned to the hospital with worsening of clinical signs, intermittent fever, intense pruritus and generalised alopecia. Blood samples were collected for haematological and serum biochemical analyses, and the mammary gland and parotid lymph nodes were biopsied. Rectal palpation revealed a large irregular mass near the left kidney with adhesions of surrounding structures. The animal died before the laboratory results were ready. This report details the clinical, histological and immunophenotypic findings of a case of large lymphoma in a mare.     

Some enzyme interrelationships in serum and organs of Egyptian camel

In 7 normal healthy Egyptian one-humped camels aged 3-4 years, the relationships were studied between enzyme activities of lactic dehydrogenase (LDH), creatine phosphokinase (CPK), alkaline phosphatase (ALP), acid phosphatase (ACP), and cholonesterase (CHE) of serum and organs as well as between ACP and ALP and between LDH and CPK. Liver, heart, kidney, and spleen tissue samples as well as serum were analysed for total enzyme activity. The following results were obtained: --The heart was the organ with the highest activities of ALP, LDH, and CPK, and it contained high values of CHE, whereas the lowest activities of all enzymes were recorded from serum. The spleen exhibited of the highest activity of ACP. --Each of the serum enzymes ALP, LDH, and CHE were in strong inverse relationship with the corresponding enzymes in the liver. Strong inverse relationships existed also between serum LDH and kidney LDH as well as between CPK in serum and heart. --Direct relationships were remarkable serum LDH and that of spleen and heart as well as between serum ACP and that of liver and heart. --Interrelationships were inverse between ACP and ALP in liver, kidney, and heart, but weak direct interrelationships were characteristic between the 2 enzymes in serum and spleen. --LDH was inversely interrelated with CPK in serum and heart.     

Estimation of genetic parameters among reproductive and growth traits in yearling heifers

Growth and reproductive data were obtained on 779 beef heifers at the San Juan Basin Research Center, Hesperus, Co. Genetic parameters were estimated for age of puberty (AOP), age of first calving (AOC), julian day of first calving (DOC), julian day of second calving (DOSC), birth weight, weaning weight, yearling weight, and average daily gain from weaning to yearling and to cycling weights. The least squares model included birth year, age of dam and breed as fixed effects, sire/breed as a random variable, and day of birth and percent inbreeding as covariates. Day of birth was not included in the analyses of AOC, DOC or DOSC. Paternal half-sib estimates of heritability were: AOP, .10 +/- .17; AOC, .01 +/- .12; DOC, .09 +/- .13 and DOSC, .36 +/- .18. Genetic and phenotypic correlations were generally favorable, but genetic correlations were variable with large standard errors. Inbreeding had a detrimental effect on reproductive traits, and a seasonal effect was present for AOP.     

Effect of group size and feeder type on growth performance and feeding patterns in finishing pigs

The effects of four group sizes (2, 4, 8, and 12 pigs per pen) and two single-space feeder types (conventional and electronic feed intake recording equipment [FIRE]) on feed intake, growth performance, and feeding patterns were determined in 208 crossbred finishing pigs (equal numbers of barrows and gilts) between 84.4 (SD = 0.81) to 112.8 (SD = 1.08) kg BW over a 4-wk period. Pigs were given ad libitum access to a corn-soybean meal-based diet (15.9% CP; 0.79% lysine; 3,328 kcal ME/kg). The floor space allowance was 0.9 m2/pig for all treatments. Growth rates were not different for the two feeder types; however, feed intake was lower and gain:feed ratio higher for pigs on the FIRE feeders (P < 0.01). Feed intake, growth rate, and gain:feed ratio were not different (P > 0.05) among the group sizes. Number of feeder visits per day decreased and feed intake per visit, feeder occupation time per visit, feed consumption rate, and percentage of time the feeder was occupied increased with group size (P < 0.05). Feed intake per visit had the strongest correlation with daily feed intake (r = 0.54; P < 0.01) and was negatively correlated with gain:feed ratio (r = -0.38; P < 0.01). However, the correlations between growth performance and other feeding pattern traits were relatively weak (r < or = 0.30). As group size increased, diurnal variation in number of feeder visits and feed consumed per hour decreased. There was no difference in time spent sitting and standing between the two feeder types. The proportion of time spent eating was generally lower for the larger groups on both feeders. The proportion of time spent lying was similar across group sizes for pigs on the conventional feeders but was greater for pigs in the larger groups on the FIRE feeders. This study suggests that finishing pigs can maintain feed intake and growth rate by changing feeding behavior as group size increases from 2 to 12.     

Identification and distribution of a novel Malassezia species yeast on normal equine skin

This study aimed to investigate the distribution of Malassezia species yeasts on the skin of healthy horses. Acetate tape samples were obtained from the lip, axilla, interbulbar region, groin and anus of 12 healthy horses. The samples were stained and examined microscopically and sites harbouring yeast-like organisms were identified. Contact plates were applied to the skin at these sites and cultured at 26 degrees C and 32 degrees C. No growth was obtained on horse blood, Sabouraud's dextrose or modified Dixon's agar. A pure growth of a Malassezia-type organism was obtained on Sabouraud's dextrose agar enriched with oleic acid when it was incubated at 30 degrees C. It was identified by 26S ribosomal DNA D1/D2 sequence analysis as a member of the genus Malassezia, and most closely related to Malassezia sympodialis. However, the level of sequence divergence indicated that it was a novel species.