Description and evaluation of a net energy intake model as a function of dietary chewing index.

Previously, a linear relationship has been found between net energy intake (NEI) and dietary chewing index (CI) of the diet for different types of cattle. Therefore, we propose to generalize and calibrate this relationship into a new model for direct prediction of NEI by dairy cows from CI values (CINE; min/MJ of NE). Furthermore, we studied the forage-to-concentrate substitution rate in this new NEI model. To calibrate the model on a diverse set of situations, we built a database of mean intake from 14 production experiments with a total of 986 primi- and multiparous lactating dairy cows of different breeds fed 136 different diets ad libitum. The NEI were estimated by the Nordic feed evaluation system. The CINE value of diets was estimated from the intake of concentrate, intake of forage neutral detergent fiber (NDFf), particle length of forage, indigestible NDFf/NDFf, body weight, NDFf/body weight, and the content of NE in DM. We show that the slope values in this regression are proportional to the squared intercepts, giving the nonlinear equation NEI=NEI0-k×NEI0a×CINE, where the parameter k represents the decline in NEI with the increasing CINE of the diet and a was estimated to have a value of 2, implying a constant maximum daily chewing time. The intercept NEI0 in the regression of NEI on CINE may be interpreted as metabolic net energy intake capacity of the cows fed without physical constraints on intake. Based on experimental data, the maximum chewing time was estimated as 1/(4 × k). The NEI0 values were parameterized as a linear function of metabolic body size, energy-corrected milk yield (kg/d), days in milk, and days in milk squared. Prediction accuracy was evaluated by mean square prediction error (MSPE) and its decomposition into central tendency, regression, and disturbance, across and within experiments on independent data from 19 experiments including 812 primi- and multiparous lactating dairy cows of different breeds fed 80 different diets ad libitum. The NEI model predicted NEI with an MSPE of 8% of observed, and across the 19 experiments the error central tendency, error regression, and error disturbance were 4.2, 40.6, and 84.9% of MSPE, respectively. The described intake model implies a variable forage-to-concentrate substitution rate as a nonlinear function of NEI0, CINE of forage, and supplementation of concentrate.

Late gestation under- and overnutrition have differential impacts when combined with a post-natal obesogenic diet on glucose-lactate-insulin adaptations during metabolic challenges in adolescent sheep.

AIM: To determine whether late gestation under- and overnutrition programme metabolic plasticity in a similar way, and whether metabolic responses to an obesogenic diet in early post-natal life depend on the foetal nutrition history. METHODS: In a 3 × 2 factorial design, twin-pregnant ewes were for the last 6 weeks of gestation (term = 147 days) assigned to HIGH (N = 13; 150 and 110% of energy and protein requirements, respectively), NORM (N = 9; 100% of requirements) or LOW (N = 14; 50% of requirements) diets. The twin offspring were raised on high-carbohydrate-high-fat (HCHF; N = 35) or conventional (CONV; N = 35) diets from 3 days to 6 months of age (around puberty). Then intravenous glucose (GTT; overnight fasted), insulin (ITT; fed) and propionate (gluconeogenetic precursor; PTT; both fed and fasted) tolerance tests were conducted to evaluate (hepatic) metabolic plasticity. RESULTS: Prenatal malnutrition differentially impacted adaptations of particularly plasma lactate followed by glucose, cholesterol and insulin. This was most clearly expressed during PTT in fasted lambs and much less during ITT and GTT. In fasted lambs, propionate induced more dramatic increases in lactate than glucose, and HIGH lambs became more hyperglycaemic, hyperlactataemic and secreted less insulin compared to the hypercholesterolaemic LOW lambs. Propionate-induced insulin secretion was virtually abolished in fasted HCHF lambs, but upregulated in fasted compared to fed CONV lambs. HCHF lambs had the greatest glucose-induced insulin secretory responses. CONCLUSION: Prenatal malnutrition differentially programmed glucose-lactate metabolic pathways and cholesterol homeostasis. Prenatal overnutrition predisposed for hyperglycaemia and hyperlactataemia, whereas undernutrition predisposed for hypercholesterolaemia upon exposure to an obesogenic diet. Prenatal overnutrition (not undernutrition) interfered with pancreatic insulin secretion by non-glucose-dependent mechanisms.

Recording rumination time by a rumination monitoring system in Jersey heifers fed grass/clover silage and hay at three feeding levels.

This study was conducted with the objective to validate a rumination monitoring system (RMS). The RMS was developed by SCR Engineers Ltd. (Netanya, Israel) to record individual rumination times in commercial dairy herds. Four heifers were fed 4 forage types at 3 feeding levels in 4 periods in a Latin square design. The forage types were spring growth of grass/clover harvested early (May 9) and late (May 25) conserved as silage and hay, creating 4 forage types: early harvest silage (ES), early harvest hay (EH), late harvest silage (LS), and late harvest hay (LH). Feeding levels were ad libitum, 90% of ad libitum, and 60% of ad libitum. Data were collected for 24 h at ad libitum feeding level, for 96 h at 90% of ad libitum, and for 24 h at 60% of ad libitum. Rumination time was recorded by the RMS in minutes per 2-h interval (RT(RMS2_i)) and per 24-h interval (RT(RMS24)). As a reference method, rumination time was recorded by chewing halters identifying rumination time by jaw movements (JM) and was accumulated into minutes per 2-h interval (RT(JM2_i)) and per 24-h interval (RT(JM24)) over the same time intervals as RT(RMS2_i) and RT(RMS24). Differences between RT(RMS2_i) and RT(JM2_i) were observed for EH, LS, and LH, with differences of 3.4 (P < 0.001), 1.1 (P = 0.03), and 3.3 (P < 0.001) min per 2-h interval. In addition, feeding restrictively at 90% and 60% of ad libitum resulted in greater rumination time recorded by the RMS compared to JM, with differences of 2.6 min per 2-h interval (P < 0.001) for 90% of ad libitum and 1.6 min per 2-h interval (P = 0.01) for 60% of ad libitum. Further, the differences between rumination times recorded by the RMS compared to JM were different among the 4 heifers. Despite these effects, rumination time recorded by the RMS correlated well with rumination time recorded by JM with correlation between RT(RMS2_i) and RT(JM2_i) of r = 0.91 (P < 0.001) and between RT(RMS24) and RT(JM24) of r = 0.79 (P < 0.001).

R-R interval variations influence the degree of mitral regurgitation in dogs with myxomatous mitral valve disease.

Mitral regurgitation (MR) due to myxomatous mitral valve disease (MMVD) is a frequent finding in Cavalier King Charles Spaniels (CKCSs). Sinus arrhythmia and atrial premature complexes leading to R-R interval variations occur in dogs. The aim of the study was to evaluate whether the duration of the R-R interval immediately influences the degree of MR assessed by echocardiography in dogs. Clinical examination including echocardiography was performed in 103 privately-owned dogs: 16 control Beagles, 70 CKCSs with different degree of MR and 17 dogs of different breeds with clinical signs of congestive heart failure due to MMVD. The severity of MR was evaluated in apical four-chamber view using colour Doppler flow mapping (maximum % of the left atrium area) and colour Doppler M-mode (duration in ms). The influence of the ratio between present and preceding R-R interval on MR severity was evaluated in 10 consecutive R-R intervals using a linear mixed model for repeated measurements. MR severity was increased when a short R-R interval was followed by a long R-R interval in CKCSs with different degrees of MR (P<0.005 when adjusted for multiple testing). The relationship was not significant in control dogs with minimal MR and in dogs with severe MR and clinical signs of heart failure. In conclusion, MR severity increases in long R-R intervals when these follow a short R-R interval in CKCSs with different degrees of MR due to asymptomatic MMVD. Thus, R-R interval variations may affect the echocardiographic grading of MR in CKCSs.

Synovial folds in equine articular process joints.

REASONS FOR PERFORMING STUDY: Cervical synovial folds have been suggested as a potential cause of neck pain in humans. Little is known about the extent and characteristics of cervical synovial folds in horses. OBJECTIVES: The objective of this explorative study was to determine the frequency of synovial folds in equine cervical articular process joints and to provide a characterisation of the size and morphology of the synovial folds. METHODS: Equine cervical articular process joints from 6 horses were included in the study, ranging from cervical vertebra 2 (C2) to cervical vertebra 7 (C7) bilaterally. The articular process joints were dissected, and the cranial and caudal synovial folds of each joint were measured and embedded in paraffin. Synovial folds were analysed histologically and classified according to type, as adipose, fibrous and mixed type. Factors potentially influencing fold size were investigated, including joint number (from C2/C3 to C6/C7), fold type, position of fold within the joint (cranial or caudal) and side of neck (right or left). RESULTS: Synovial folds were identified in 98% of cervical articular process joints examined. The width of the synovial folds varied from 4 to 41 mm, and the height from 1 to 17.8 mm. Thirty-eight per cent of the synovial folds were of adipose type, 41% of fibrous type and 21% of mixed type. Synovial fold size was significantly influenced by the side of the neck and fold type. CONCLUSIONS AND POTENTIAL RELEVANCE: This study provides a characterisation of the frequency, size and morphology of equine cervical synovial folds in 6 horses. Synovial folds were present in 98% of the cervical articular process joints examined, and the size of the synovial folds indicates that they could be damaged by acute injury or chronic disease in the cervical articular process joints.

Escherichia coli contamination and health aspects of soil and tomatoes (Solanum lycopersicum L.) subsurface drip irrigated with on-site treated domestic wastewater.

Faecal contamination of soil and tomatoes irrigated by sprinkler as well as surface and subsurface drip irrigation with treated domestic wastewater were compared in 2007 and 2008 at experimental sites in Crete and Italy. Wastewater was treated by Membrane Bio Reactor (MBR) technology, gravel filtration or UV-treatment before used for irrigation. Irrigation water, soil and tomato samples were collected during two cropping seasons and enumerated for the faecal indicator bacterium Escherichia coli and helminth eggs. The study found elevated levels of E. coli in irrigation water (mean: Italy 1753 cell forming unit (cfu) per 100 ml and Crete 488 cfu per 100 ml) and low concentrations of E. coli in soil (mean: Italy 95 cfu g(-1) and Crete 33 cfu g(-1)). Only two out of 84 tomato samples in Crete contained E. coli (mean: 2700 cfu g(-1)) while tomatoes from Italy were free of E. coli. No helminth eggs were found in the irrigation water or on the tomatoes from Crete. Two tomato samples out of 36 from Italy were contaminated by helminth eggs (mean: 0.18 eggs g(-1)) and had been irrigated with treated wastewater and tap water, respectively. Pulsed Field Gel Electrophoresis DNA fingerprints of E. coli collected during 2008 showed no identical pattern between water and soil isolates which indicates contribution from other environmental sources with E. coli, e.g. wildlife. A quantitative microbial risk assessment (QMRA) model with Monte Carlo simulations adopted by the World Health Organization (WHO) found the use of tap water and treated wastewater to be associated with risks that exceed permissible limits as proposed by the WHO (1.0 × 10(-3) disease risk per person per year) for the accidental ingestion of irrigated soil by farmers (Crete: 0.67 pppy and Italy: 1.0 pppy). The QMRA found that the consumption of tomatoes in Italy was deemed to be safe while permissible limits were exceeded in Crete (1.0 pppy). Overall the quality of tomatoes was safe for human consumption since the disease risk found on Crete was based on only two contaminated tomato samples. It is a fundamental limitation of the WHO QMRA model that it is not based on actual pathogen numbers, but rather on numbers of E. coli converted to estimated pathogen numbers, since it is widely accepted that there is poor correlation between E. coli and viral and parasite pathogens. Our findings also stress the importance of the external environment, typically wildlife, as sources of faecal contamination.

Allergen extract of horse hair and dandruff. Quantitative immunoelectrophoretic characterization of the antigens.

Freeze-dried extract of horse hair and dandruff was obtained by extraction, centrifugation, dialysis and freeze-drying. Quantitative immunoelectrophoresis using rabbit antibodies revealed the extract to be composed of 25 antigens of which some were mutually partial identical; 4 were serum-specific and non showed partial identity to solubilized hair proteins. Partial identity to antigens to serum and extract from hair and dandruff of cow, dog, cat, guinea pig, and of extract from house duct was demonstrated. After subjecting the extract to dialysis, ultrafiltration, freeze-drying and storage below 37degreesC for not more than 24 h the antigenic stability and the allergenic activity were unaffected. The effect of enzymatic degradation of the individual proteins with regard to antigenic stability and allergenic activity was also examined.

Identification of allergens in extract of horse hair and dandruff by means of crossed radioimmunoelectrophoresis.

Sera from 26 patients and 4 normals were examined for specific IgE binding to antigens of extract of horse hair and dandruff by means of CRIE. 22 of the patients were RAST- and intracutaneous-positive to horse extract. 4 more of the patients were RAST-negative to horse allergens, but showed allergies to extract of allergens from sources other than horse. The remaining four sera from controls were RAST-negative to horse and had no history of allergy. Antigens of horse hair and dandruff showed a significantly higher degree of binding to specific IgE in the sera from the first group of patients than was the case for the two other groups. A linear correlation between specific IgE binding in RAST and in CRIE was found for the first group of patients. On the basis of these results the major allergens of the examined extract of horse hair and dandruff were identified.

Isolation and partial characterization of three major allergens of horse hair and dandruff.

Three major allergens of horse hair and dandruff have been isolated. The fractionation procedures involved various combinations, described in detail, of ethanol precipitation below --5degreesC, cation- and anion-exchange chromatography, and gel filtration. UV absorption, quantitative immunoelectrophoresis and RAST inhibition were used to monitor the separations. Protein impurities constituted less than 5% in all cases. The molecular weights of the isolated proteins were 1.9 X 10(4), 5.1 X 10(4) and 3.1 X 10(4) daltons, respectively. The pIs were determined as 4.1, 3.8 and 3.9, respectively. The amino acid analysis of the isolated allergens revealed large variations in their amino acid composition which might explain different reactivities in RAST experiments. The allergenic activities of the isolated antigens were determined by RAST inhibition and prick tests.