摘要:

The influence of rapeseed oil on digestibility, energy metabolism and tissue composition in growing pigs was determined. Rapeseed oil (0, 4, 8 and 16%) was added to a soyabean meal and barley basal diet. Essential amino acids relative to net energy (NE) were kept constant by adjusting with crystalline amino acids. Rapeseed oil has a high content of the unsaturated fatty acids 18:1n-9, 18:2n-6 and 18:3n-3, and is rich in natural tocopherols, which act as antioxidants. The apparent protein digestibility was enhanced with increasing levels of rapeseed oil. Improving the ratio of essential to non-essential amino acids decreased nitrogen execretion in faeces and urine by 21% and 26%, respectively. The amount of digestible fat increased from 29 to 218 g day−1from the control diet to the diet with 16% rapeseed oil, resulting in a fat retention of 195 to 213 g day−1. This demonstrates the ability of pig forde novosynthesis of fatty acids. The digestibility of the rapeseed oil was high (92.7), and the metabolizable energy (ME) content of rapeseed oil was 38.28 MJ ME kg−1. The net energy value of the rapeseed oil corresponded to 3.66 kg air dry barley. Higher intakes of unsaturated fatty acids in rapeseed oil were reflected in the body tissue composition of both depot fat and intramuscular fat of the pigs. The fatty acid composition of these tissues became more unsaturated with respect to 18:2n-6 and 18:3n-3 as well as 20:5n-3 and 22:5n-3. Arachidonic acid (20:4n-6) increased slightly in leaf fat but tended to decrease inM. longissimus dorsiandM. biceps femoris, where docosahexaenoic acid (22:6n-3) in leaf fat was unaffected by dietary rapeseed oil level. In the analysed muscles 22:6n-3 tended to decrease with increasing dietary rapeseed oil level.

ISSN:0906-4702    

DOI:10.1080/09064709609415854

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

The properties of isolated sheets of bovine rumen epithelium in the Ussing chamber system were studied. The viability and time-dependent change in performance, as expressed by electrical parameters, was acceptable and comparable to what has been obtained with other epitheliain vitro. The viability and time-dependent change in performance was not influenced by transport time (5 to 45 minutes) between the slaughterhouse and the laboratory. Flux rates of22Na+and14C-propionate showed that an equilibration period of 45 minutes after addition of tracers will be sufficient to obtain steady-state conditions with this epithelium. Compared with the time-dependent changes in electrical parameters, this shows that rumen epithelium cannot truly be used as its own control over time. The varying papillation caused surface enlargement factors between one and five, estimated by the dry weight of stripped epithelium. However, the dry weight was not correlated to epithelial capacitance or flux rates. It is concluded that the papillae do not contribute significantly to the fluxes measuredin vitro, and that correction for surface enlargement is not essential for the evaluation of flux data. The pH was 0.27 to 0.40 units lower at the epithelial surface than in the bulk solution, and the pH difference was not influenced by glucose or SCFA free solutions, nor by Amiloride (1 mmol 1−1). The observed lower epithelial surface pH seems not to be an acidic microclimate in the traditional sense, but could be explained by a negatively charged surface potential of the epithelial cells.

ISSN:0906-4702    

DOI:10.1080/09064709609415855

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Herbage intake by strip-grazed dairy cows was estimated, using chromic oxide as marker, during experimental periods covering different parts of the grazing season, different sward heights and different years. Herbage mass, herbage composition and the milk yield, live weight, lactation week and age of experimental animals were also registered with the objective of including those variables that were significant in a model for studying the influence of sward height and season on herbage intake. Pastures were grazed when planned target sward height was obtained. Average sward height over all experimental periods was 15.0 cm (range 7.4-21.2). The grazing season was divided into early season (May 17 to June 19), mid-season (June 20 to July 31) and late season (August 1 to August 20). The data comprise herbage intake measurements on 69 dairy cows with an average milk yield and live weight of 15.6 kg/day and 546 kg, respectively. Pasture allowance was 30 kg dry matter/cow and day. The content of metabolizable energy and the digestibility of organic matter in the pasture was 11.2, 10.2 and 10.2 MJ/kg DM and 77.8, 72.4 and 72.4% for early, mid- and late season, respectively. The variables sward height, season, milk yield, live weight and year, and the interaction between sward height and season, were significant in the statistical analysis and were thus included in the model. In early season, herbage intake increased by 0.8 kg organic matter (OM) per cm increase in sward height. In mid-season, intake was significantly lowered at pasture heights below 9 cm, while in late season there were no differences in intake at different sward heights. Least square means for herbage intake during the early, mid- and late season were 12.8, 12.3 and 10.2 kg OM per cow and day, respectively. Late season intake was significantly lower (P< 0.001 andP<0.01) compared with intake during early season and mid-season, respectively. In the model obtained, the influence of milk yield and live weight on herbage OM intake was 0.2 kg OM per kg milk and 0.5 kg OM per 100 kg live weight, respectively.

ISSN:0906-4702    

DOI:10.1080/09064709609415856

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

The objectives were to study fodder galega concerning (1) its composition, digestibility and feeding value, (2) the relationship between the concentration ofin vitroorganic matter disappearance (IVOMD) and the concentration ofin vivodigestibility of organic matter (DOM), and between the concentration of gross energy (GE) and DOM and the concentration of digestible energy (DE), and (3) the difference between DE calculated on basis of chemical composition of DOM andin vivoDE. The study was based on digestibility trials with sheep on 17 samples of fodder galega in connection with a harvest management experiment in which cutting frequency and time of first harvest varied. The main results were, first, that the concentration of crude protein, DOM (in vivo), DE (in vivo) and feed units for cattle (FUC) decreased by delaying harvest of the first cut. The concentration of fibre expressed as crude fibre, neutral detergent fibre (NDF) and acid detergent fibre (ADF) increased by delaying harvest at the first and following cuts. Fodder galega differed from other legumes not included in this study by having a higher concentration of hemicellulose calculated as NDF-ADF, while the mean concentration of DE (in vivo) and FUCwas nearly equal to the mean concentration in red clover, winter vetch and yellow lupins. Secondly, DOM in fodder galega may be predicted by using an equation based on the concentration of IVOMD, and DE in fodder galega may be predicted by using another equation based on the concentrations of GE and DOM. The two equations were developed on the basis of this investigation of fodder galega. Thirdly, DE predicted on the basis of the chemical composition of DOM in fodder galega deviated considerable fromin vivoDE. The conclusions were that the chemical composition, digestibility and feeding value of fodder galega changed when the yield increased by delaying harvest, especially at the first cut.

ISSN:0906-4702    

DOI:10.1080/09064709609415857

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Full-scale experiments with cooling of raw milk of good initial quality from a herd of 70 dairy cows have been performed under practical farm conditions, with different cooling and storage conditions, including instant cooling in a continuous process versus normal cooling in a batch process. During each milking, the milk was divided equally and successively for different cooling procedures. Quality evaluations (number of bacteria, acidity and oxidation of fat, sensoric quality) indicated that instant cooling/continuous process compared with normal cooling/batch process over 2.5 hours, both to 4°C, resulted in a slightly slower bacterial growth and a slightly slower hydrolysis and oxidation of milk fat. Instant raw milk cooled and stored at 2.5°C maintained a good quality for about one to two days more than when normal cooling over 1.5 hours and storing at 4°C was used.

ISSN:0906-4702    

DOI:10.1080/09064709609415858

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

It is of great importance to be able quantitatively to evaluate the stress to which captive fur animals are subjected to by various forms of management. A range of haematological and hormonal parameters have been shown to be good indicators of stress. However, blood sampling, which entails the presence of humans and handling of the animals, can itself be a stressor that influences the results of an experiment. The present study shows that a group of silver foxes (n= 7) that had been regularly blood sampled (RBS-group) for a year had higher plasma concentrations of cortisol and lower concentrations of testosterone compared with an earlier non-blood-sampled group (NBS-group) (n= 7). The RBS-group also tended to have a lower number of lymphocytes. In addition, during a series of five blood samples taken at 30 min intervals, both groups showed an increase in plasma concentrations of cortisol, whereas numbers of lymphocytes and eosinophil leucocytes decreased. Plasma testosterone concentrations decreased after an initial increase. The study demonstrated that blood sampling, in both the long and short term, can profoundly affect hormone concentrations and leucocyte numbers.

ISSN:0906-4702    

DOI:10.1080/09064709609415859

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

The preferences of juvenile farmed silver foxes (n= 14) and blue foxes (n= 12) for an empty cage (105L × 115W × 70H cm) and a cage of equal size with a wooden nest box were assessed in an 11-day preference test. The silver foxes spent a higher percentage of their time (86 ± 8%) in the nest box cage than the blue foxes (66 ± 21%). The silver foxes, but not the blue foxes, had a strong preference for the nest box roof as a resting site (44% of total daily time). Assuming that greater use indicates a greater need, silver foxes may benefit more from the nest boxes than blue foxes.

ISSN:0906-4702    

DOI:10.1080/09064709609415860

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

ISSN:0906-4702    

DOI:10.1080/09064709609415861

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

This is a scanned image of the original Editorial Board page(s) for this issue.

ISSN:0906-4702    

DOI:10.1080/09064709609415853

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor