Energy exchanges of broilers, selected for fatness and leanness, on diets with and without a repartitioning agent.

1. Two experiments were undertaken for 3 or 5 d in respiration chambers, on two experimental lines of broiler chickens (aged 25-38 d) selected for leanness and fatness. Diets were without or with 0.4 mg cimaterol per kg. 2. The lean line with sexes combined (experiment 1), or with females only, had a significantly greater heat production than the fat line. Net availability of metabolisable energy for gain (kg) was 0.54 for the lean birds and and 0.84 for the fat birds. 3. Cimaterol did not have an effect on any of the variables examined.     

Fine structure of atrial natriuretic peptide(ANP)-granules in the atrial cardiocytes in the pig, cattle and horse.

In the pig, cattle and horse, the right and left atria and ventricles were examined by immunohistochemistry, and the right atrial and auricular cardiocytes were studied by transmission electron microscopy. Moreover, ANP-granules in the cardiocytes were analyzed by ultrastructural morphometry. Immunohistochemically, the most intensely ANP-reacted cardiocytes were localized in the right auricle, particularly more prominent in the pig and cattle than in the horse. Ultrastructurally, ANP-granules were located principally in the perinuclear region associated with the Golgi apparatus and throughout the sarcoplasmic layers. They were classified into 2 types, A and B. A-granule had a conspicuous electron-dense core enveloped by a membrane. B-granule had a fibrillogranular core enveloped by an indistinct membrane. By TEM equipped with a goniometer stage, a part of the limiting membrane of B-granules became visible as the stage tilt progressed. By ultrastructural morphometry, the number of each type of granules was significantly greater in the pig and cattle than in the horse. In the pig and cattle, the total number of both types of granules in the auricular cardiocytes was significantly greater than that in the atrial ones. The diameter of each type of granules was significantly larger in the pig and cattle than in the horse. The diameter of A-granules was significantly larger than that of B-granules.     

Clinical use of tissue adhesives in the closure of udder wounds in lactating ewes and goats.

Twenty-seven udder wounds in lactating goats and ewes were treated and closed with synthetic tissue adhesive. Twenty-four healed by primary intention (89%), two wounds were partially healed by primary intention and partially by second intention and a wound failed to heal and developed milk fistula. In general, non suture closure of skin wounds using tissue adhesive proved to be satisfactory and highly efficient in small ruminants.     

Supplementary report on experimental autumn crocus (Colchicum autumnale L.) poisoning in cattle: morphological evidence of apoptosis.

Previously we reported that tissue destruction characterized by the presence of karyopyknotic, karyorrhectic and mitotically arrested cells was seen in alimentary epithelial cells and lymphocytes in the lymphoid and hemopoietic systems of cattle experimentally administered with autumn crocus (Colchicum autumnale L.). This report deals with the mechanism of acute cellular injury following experimental autumn crocus poisoning in cattle as demonstrated by the in situ DNA strand break analysis and electron microscopy. The analyses revealed that cellular injury caused by autumn crocus was closely associated with apoptosis.     

Use of canine red blood cell with high concentrations of potassium, reduced glutathione, and free amino acid as host cells for in vitro cultivation of Babesia gibsoni

OBJECTIVE: To determine the usefulness of canine RBC with high concentrations of potassium, reduced glutathione (GSH), and amino acid(i.e., HK cells) for in vitro cultivation of Babesia gibsoni. ANIMALS: RBC were obtained from 3 dogs that had inherited HK cells and from 3 genetically unaffected dogs that, therefore, had RBC with lower potassium (LK) concentrations (i.e., LK cells). PROCEDURES: First, B. gibsoni were cultivated using HK or LK cells in alpha-modification of Eagle medium, consisting of Earle salts with glutamine and without ribosides, deoxyribosides, and sodium bicarbonate under a humidified atmosphere containing 5% CO2 at 37 C. Second, parasites were cultivated with LK- or HK-cell lysates. Finally, HK cells were separated into 3 fractions (bottom, middle, top layers) by density gradient centrifugation, and B. gibsoni were cultivated with each of the HK-cell fractions. In addition, the concentrations of free amino acids and reduced glutathione (GSH) in each HK-cell fraction were measured. RESULTS: B. gibsoni preferentially multiplied in HK-cell cultures rather than in LK-cell cultures. Furthermore, the addition of HK-cell lysate to the culture medium resulted in enhanced multiplication of the parasites. Higher multiplication of the parasites was observed in HK cells from the top layer, compared with HK cells from the middle and bottom layers. The HK cells from the top layer had higher concentrations of glutamate, aspartate, and GSH, compared with HK cells from the middle and bottom layer. CONCLUSIONS: Canine HK cells are useful host cells for in vitro cultivation of B. gibsoni, and the high concentrations of glutamate, aspartate, and GSH may result in enhancement of multiplication of the parasites in HK cells.     

Methane output and diet digestibility in response to feeding dairy cows crude linseed, extruded linseed, or linseed oil

This experiment studied the effect of 3 forms of presentation of linseed fatty acids (FA) on methane output using the sulfur hexafluoride tracer technique, total tract digestibility, and performance of dairy cows. Eight multiparous lactating Holstein cows (initial milk yield 23.4 +/- 2.2 kg/d) were assigned to 4 dietary treatments in a replicated 4 x 4 Latin square design: a control diet (C) consisting of corn silage (59%), grass hay (6%), and concentrate (35%) and the same diet with crude linseed (CLS), extruded linseed (ELS), or linseed oil (LSO) at the same FA level (5.7% of dietary DM). Each experimental period lasted 4 wk. All the forms of linseed FA significantly decreased daily CH(4) emissions (P < 0.001) but to different extents (-12% with CLS, -38% with ELS, -64% with LSO) compared with C. The same ranking among diets was observed for CH(4) output expressed as a percentage of energy intake (P < 0.001) or in grams per kilogram of OM intake (P < 0.001). Methane production per unit of digested NDF was similar for C, CLS, and ELS but was less for LSO (138 vs. 68 g/kg of digested NDF, respectively; P < 0.001). Measured as grams per kilogram of milk or fat-corrected milk yield, methane emission was similar for C and CLS and was less for ELS and LSO (P < 0.001), LSO being less than ELS (P < 0.01). Total tract NDF digestibility was significantly less (P < 0.001) for the 3 supplemented diets than for C (-6.8% on average; P < 0.001). Starch digestibility was similar for all diets (mean 93.5%). Compared with C, DMI was not modified with CLS (P > 0.05) but was decreased with ELS and LSO (-3.1 and -5.1 kg/d, respectively; P < 0.001). Milk yield and milk fat content were similar for LSO and ELS but less than for C and CLS (19.9 vs. 22.3 kg/d and 33.8 vs. 43.2 g/kg, on average, respectively; P < 0.01 and P < 0.001). Linseed FA offer a promising dietary means to depress ruminal methanogenesis. The form of presentation of linseed FA greatly influences methane output from dairy cows. The negative effects of linseed on milk production will need to be overcome if it is to be considered as a methane mitigation agent. Optimal conditions for the utilization of linseed FA in ruminant diets need to be determined before recommending its use for the dairy industry.     

Pharmacokinetics and bioavailability of cefquinome in healthy piglets

A study on bioavailability and pharmacokinetics of cefquinome in piglets was conducted after intravenous (i.v.) and intramuscular (i.m.) administrations of 2.0 mg/kg of body weight, respectively. Plasma concentrations were measured by high‐performance liquid chromatography assay with UV detector at 268‐nm wavelength. Plasma concentration–time data after i.v. administration were best fit by a two‐compartment model. The pharmacokinetic values were distribution half‐life 0.27 ± 0.21 h, elimination half‐life 1.85 ± 1.11 h, total body clearance 0.26 ± 0.08 L/kg·h, area under curve 8.07 ± 1.91 μg·h/mL and volume of distribution at steady state 0.46 ± 0.10 L/kg. Plasma concentration–time data after i.m. administration were also best fit by a two‐compartment model. The pharmacokinetic parameters were distribution half‐life 0.88 ± 0.42 h, elimination half‐life 4.36 ± 2.35 h, peak concentration 4.01 ± 0.57 μg/mL and bioavailability 95.13 ± 9.93%.     

Effects of dietary oregano and garlic essential oils on carcass characteristics,meat composition,colour, pH and sensory quality of broiler meat

1. An experiment was conducted to determine the individual and combined effects of two essential oils, oregano and garlic, on carcass characteristics, meat composition, colour, pH and sensory quality of broiler meat.

2. The diets were supplemented with no essential oil (control), oregano essential oil or garlic essential oil at 300 mg/kg and oregano essential oil at 150 mg/kg + garlic essential oil at 150 mg/kg.

3. Dietary oregano and garlic oil supplementation did not affect carcass yields, the relative weight of carcass parts, breast and thigh meat composition, pH or b* value of breast meat. Oregano + garlic oil supplementation significantly decreased the L* value. The a* value of breast meat in birds given a diet supplemented with oregano oil was lower than that in birds given a diet supplemented with garlic oil and oregano oil + garlic oil. The essential oil addition had no positive effect on the oxidative stability. There was no difference between the treatments in breast appearance.

4. The juiciness, flavour, oxidised flavour and acceptability of breast meat samples were affected by treatments.