bluuebunny/crossref_metadata_2025 huggingface dataset:
The inheritance of fibre traits in a crossbred population of cashmere goats
Authors: Bishop S. C. , Russel A. J. F.
Published: September 2010

Genetic parameters were calculated for fibre traits measured on patch samples taken at 5 months of age on a crossbred population of cashmere goats, comprising goats of Scottish feral, Icelandic, Tasmanian, New Zealand and Siberian origin. Within-strain heritabilities, fitting genetic origin as a covariable, were: live weight, 0·71 (s.e. 0·08), fibre diameter, 0·63 (0·07), diameter standard deviation 0·43 (0·08), logipatch cashmere weight), 0·60 (0·06), log(estimated annual cashmere production), 0·51 (0·07), and fibre length, 0·49 (0·15). Including between strain information increased these values to 0·74, 0·68, 0·45, 0·73, 0·67 and 0·57, respectively. Maternal effects for all fibre traits were negligible. Expressions were derived to relate cashmere weight to fibre diameter and length, using functional relationships between these traits. Logarithmic regressions showed cashmere weight to be proportional to diameter2'7, indicating that selection to reducefibre diameter will have a disproportionate effect on cashmere weight. Analyses of subsets of the data confirmed this and showed that correlated responses to selection can be accurately predicted by considering thefunctionally relatedfibre traits on the log scale.
The effects of cross, slaughter weight and halothane genotype on leanness and meat and fat quality in pig carcasses
Authors: García-Macías J. A. , Gispert M. , Oliver M. A. , Diestre A. , Alonso P. , Muñoz-Luna A. , Siggens K. , Cuthbert-Heavens D.
Published: September 2010

Carcass and meat quality traits were studied in 94 barrows of known HAL-1843 genotype (homozygote - - and heterozygote - +) from three crosses slaughtered at 90 kg and 120 kg live weight. Crosses A and B were produced from sires of which 0·5 of the genes were from a heavy-muscled × Large White line and 0·5 from pure Pietrain (A) or Duroc (B). Sows for both A and B were from a hyperprolific Large White × Landrace line and this latter line produced the pigs for cross C (control). The carcasses from cross A which were sired from boars having 0·75 of their genotype from heavy-muscled genetic lines had higher killing-out proportion, better conformation scores, greater loin depth and loin area, less carcass length and bone content, and greater lean proportion compared with cross C. The carcasses from cross B, with roughly 0·25 of Duroc genes had a significantly higher backfat thickness than either cross A or C. However their composition was not significantly different from C, since the higher backfat was counter-balanced by their better conformation. Carcass and lean weight distribution was more favourable in crosses A and B, which had significantly higher economic yields than cross C. The halothane genotype did not have a significant effect on fatness and carcass composition, although the heterozygote showed a significantly greater muscle depth. In addition, no significant effect of the halothane gene on carcass and lean weight distribution was observed. In relation to the light group of carcasses (72·8 (s.e. 4·4) kg), the heavy group (100·1 (s.e. 2·7) kg) had greater killing-out proportion, better conformation, longer carcasses, higher fatness and greater loin depth and area. These genetic lines showed a 9·6 g/kg increase in fat and a 6·1 g/kg decrease in lean for every 10 kg of increasing slaughter weight. With the slaughter weight increase the longissimus dorsi muscle became less pale due to a higher muscle pigment concentration, and the backfat had a higher proportion of oleic and lower proportion of linoleic and palmitic fatty acids. The halothane genotype had a significant effect on meat quality. The heterozygote produced much paler, softer and more exudative meat. However, the effect of cross and carcass weight was not significant for meat quality measurements determining pale, soft and exudative meat.
The influence of short-term feeding of amino acid-deficient diets and high dietary leucine levels on the intramuscular fat content of pig muscle
Authors: Cisneros F. , Ellis M. , Baker D. H. , Easter R. A. , McKeith F. K.
Published: September 2010

The objective of the study was to investigate the influence of amino acid-deficient diets and high dietary leucine levels offered for intervals of either 21 or 35 days pre-slaughter on the intramuscular fat content of pig muscle. Twenty-four hybrid gilts were offered individually ad libitum one of four diets that comprised combinations of amino acid levels (supplemented or deficient: 5·6 v. 4·0 g lysine per kg) and low or high leucine levels (10·3 v. 30·3 g leucine per kg). Live weights at the start of the study were 74·5 and 87·0 kg for pigs on the 35- and 21-day feeding regimens, respectively. There were no significant effects of dietary amino acid level, leucine level, or feeding interval on food intake, daily live-weight gain or food efficiency. Pigs given the amino acid-deficient diets had lower killing-out proportions (736 v. 747 (s.e. 3·4) g/kg; P < 0·05) and longissimus dorsi muscle areas (32·6 v. 35·7 (s.e. 0·71) cm2, P < 0·01) than those given amino acid-supplemented diets. Subjective score for longissimus dorsi colour indicated that pigs on the high leucine diet had darker muscle than those on the low leucine diet. Intramuscular fat contents of the longissimus dors i muscle at the Wth/llth rib and the 3rd/4th lumbar vertebra and of the semimembranosu s muscle were increased by 19, 18 and 18 g/kg, respectively (P < 0·05), for pigs given amino acid-deficient compared with those given amino acid-supplemented diets. Dietary leucine level had no significant effect on intramuscular fat level. Pigs given the diets for 35, compared with 21, days had higher fat levels in the semimembranosu s muscle (52 v. 30 (s.e. 5·2) g/kg; P < 0·01) but not in the other two muscle locations studied. This study suggests that relatively short-term feeding of amino acid-deficient diets can produce substantial increases in intramuscular fat levels.
The need to complementin vitrogas production measurements with residue determinations fromin saccodegradabilities to improve the prediction of voluntary intake of hays
Authors: Blümmel M. , Bullerdieck P.
Published: September 2010

The need to complement in vitro gas production measurements with residue determination is demonstrated by the recalculation and reassessment of published data on in vitro gas production, in sacco degradabilities and voluntary dry matter intake (DMI). The in sacco degradability — gas volume ratio was determined at 24 and 48 h of incubation, termed partitioning factor (PF) and combined with rate and extent parameters of in sacco degradability and in vitro gas production to predict DMI. In vitro gas production and in sacco degradability characteristics (a + b) and c as described by the equation y = a + b(1−ect) explained 0·373 and 0·668 respectively of the variation in DMI of 19 legume and grass hays. The complementation of gas production parameters by the PF24increased the R2value to 0·744 with PF24accounting for 0·407 of the variation in DMI, the rate of gas production (c) for 0·218 and the extent of gas production (a + b) for 0·119 of the variation in DMI. As a single parameter, PF48showed the highest correlation (R2= 0·597) with DMI but the combination of PF4Swith rate and extent of in sacco or in vitro gas production measurements did not improve the correlation further, probably due to an intercorrelation between rates of fermentation and PF4S. Hays which were degraded at faster rates had higher PF values indicating proportionally higher microbial yield and lower short-chain fatty acid production per unit substrate degraded. Generally, hays with high in sacco degradabilities but proportionally low gas production i.e. hays with high PF values showed higher DMI.
Threonine requirement of growing pigs (50 to 95 kg) in relation to diet composition
Authors: Schutte J. B. , de Jong J. , Smink W. , Koch F.
Published: September 2010

A study was conducted to evaluate increasing dietary levels of threonine on performance and carcass quality of growing gilt pigs (live-weight period of 50 to 95 kg; no. = 384) by using two different types of basal diets. One basal diet (basal A) was composed of highly digestible food ingredients and the other diet (basal B) of less well digested food ingredients. Before starting the growth trial, Heal apparent digestibility ofamino acids of both basal diets was determined in an in vivo digestibility trial with pigs. Both basal diets were composed in such a way as to obtain equal contents for net energy and Heal digestible threonine, lysine, methionine + cystine and tryptophan. The content of Heal digestible threonine in both basal diets was approximately 3·3 g/kg, corresponding with a total threonine content of 4·8 g/kg in basal diet A and 5·4 g/kg in basal diet B. To both diets three graded dose levels (0·4, 0·8 and 1·2 g/kg) of L-threonine were added, providing at the highest supplemented level 4·5 g/kg Heal digestible threonine. The requirement for Heal digestible threonine was estimated to be 4·1 g/kg regardless of diet composition. This estimated requirement was mainly based on the results for food conversion efficiency. For obtaining maximum weight gain, the requirement for Heal digestible threonine was found to be somewhat higher than for maximum efficiency of food utilization. The estimated requirement figure of 4·1 g Heal digestible threonine corresponded with approximately 5·6 g total threonine per kg in basal diet A and 6·2 g/kg in basal diet B. Carcass quality was not affected by the content of threonine in the diets.
Nutrition of draught oxen in semi-arid west Africa 3. Effect of body condition prior to work and weight losses during work on food intake and work output
Authors: Fall A. , Pearson R. A. , Fernández-Rivera S.
Published: September 2010

Eighteen oxen were allotted to three treatment groups according to their body condition: poor, medium and good. Work output, speed, live weight and body condition were measured during 7 weeks when animals worked 4 days/ week, 4 h/day, pulling loads equivalent to 12-5 kgf/100 kg live weight. The animals were given millet stover ad libitum during hours they did not work plus 10 g/kg M of a concentrate mix. Work did not influence intake of millet stover. However, food intake improved as work progressed and animals in bad condition ate more millet stover than animals in good body condition. Work performance was affected by live weight but not body condition. Live-weight losses did not have a detrimental effect on work performance. Power output improved during the course of the experiment while animals were losing weight Animals in all treatment groups lost body weight during the 7 weeks of work but weight losses were more pronounced in oxen in good than in poor body condition. At the end of the working period, animals were put on natural pastures without supplementation. It took 4 weeks for animals in poor and medium body condition and 6 weeks for animals in good body condition to reach their pre-work live weight.
Genetic correlations between linear type traits, food intake, live weight and condition score in Holstein Friesian dairy cattle
Authors: Veerkamp R. F. , Brotherstone S.
Published: September 2010

Variance components were estimated from an animal model using a restricted maximum likelihood procedure which allowed for unequal design matrices and missing observations (VCE). Data sets containing: (i) 15 275 records of linear type classifications on heifers, (ii) 3399 live weight and condition scores measured at calving and (iii) 1157 records of yield, dry-matter intake, average live weight and condition score during the first 26 weeks of lactation; were analysed jointly.

Heritability estimates for dry-matter intake, live weight and condition score in the largest data set were 0·44, 0·44 and 0·35 respectively and the genetic correlation between condition score and the yield traits ranged from −0·29 to −0·46. The genetic correlation between milk yield and average live weight was negative (−0·09) but after adjusting for the genetic variation in condition score this correlation was positive (0·29). Genetic correlations between live weight and stature, chest width, body depth and rump width were consistently high (0·52 to 0·64; 0·75 to 0·86; 0·59 to 0·81; 0·56 to 0·74, respectively). Chest width and body depth were little to moderately correlated with dry-matter intake (0·25 to 0·28 and 0·20 to 0·34 respectively), and angularity (−0·47 to −0·77) and chest width (0·32 to 0·73) appeared to be good predictors of condition score. These correlations showed that (i) the relative value of live weight compared with food intake capacity determines the optimum direction of selection for stature, chest width, body depth and angularity, and consequently the optimum size of the dairy cow, and that (ii) live weight, condition score and food intake can be predicted from the type traits with little loss in accuracy. A restricted index which maintains condition score at its current level was predicted to reduce overall (economic) genetic gain by 5%.
Use of a stochastic model of a calving distribution for beef cows for formulating optimal natural mating strategies
Authors: Pleasants A. B.
Published: September 2010

A model of a birthdate distribution for a herd of beef cows is constructed using the probability distributions of the variables that affect reproduction in the cow — anoestrous interval, oestrous cycle length, conception to each oestrus, gestation length, period of mating and the prior calving frequency distribution. The model is general and can be reparamaterized to deal with issues such as intervention to synchronize oestrous cycles among cows in the herd by changing the form of the relevant probability distributions.

The model is applied to the question of what time to begin mating in a herd of beef cows. The average calf live weight at day 200, herd conception rate and proportion of cows calving before the planned start of calving were calculated from the model output. The model parameters given by the anoestrous period, conception rate to each oestrus and the regression between prior calving date and anoestrous period, were varied in a factorial design to investigate a range of circumstances found on a farm. Prior calving distributions were generated by random sampling from eight actual calving frequency distributions.

Generally starling mating earlier produced an advantage in terms of extra calf live weight and herd conception rate. However, the proportion of the herd calving earlier than expected increased with early mating. Thus, the feasibility of early mating depends on the cost to the farmer of dealing with early calving cows as well as the advantage of heavier older calves.

Altering the fixed parameters in the model (variances and covariances, prior calving distributions, mating period) to accommodate the circumstances of herds run under different conditions may produce different results. Model structure allows easy alteration of these parameters and also the introduction of different probability distributions for some variables. This might be necessary to model oestrous synchronization and artificial insemination, issues not considered in this paper.
Effect of ammonia treatment or protein supplementation on rumination behaviour in sheep given barley straw
Authors: Mawuenyegah P. O. , Warly L. , Harumoto T. , Fujihara T.
Published: September 2010

A study was conducted to compare the effects of ammoniation and protein supplementation of barley straw on rumination behaviour of sheep. Four wethers were allocated to four diets offered ad libitum in a 4 × 4 Latin-square design. The diets were, untreated barley straw + molasses meal (diet 1), untreated barley straw + soya-bean meal + molasses meal (diet 2), ammonia-treated barley straw + molasses meal (diet 3) and ammonia-treated barley straw + soya-bean meal + molasses meal (diet 4). Animals were kept in metabolism crates throughout each 16-day experimental period and allowed free access to water and a mineralized salt lick. The first 11 days of each period were for adaptation to the harnesses and diets while the last 5 days were used for rumination studies. Animals given diets 3 and 4 had slower eating rates compared with those given diets 1 and 2. Rumination index and duration of each rumination period was lower for sheep consuming diets 3 and 4 than for those on diets 1 and 2 but not significantly so (P > 0·05). Rumination time per 100 g neutral-detergent fibre (NDF) intake was significantly lower (P < 0·01) for diets containing ammoniated straw. Animals given ammoniated straw diets also regurgitated fewer boluses per unit NDF intake than did those on untreated straw diets. The results showed that increased intake and digestibility, which is usually associated with ammoniated straws, was due to sheep doing less work per unit of time to break down straw for digestion. In this way, potentially digestible tissues within a given amount of straw is more readily exposed. The foregoing suggests that ammonia treatment results in less rumination so that ruminants given ammonia-treated straw diets do less work ruminating.
The phenotypic association between the interval to post-partum ovulation and traditional measures of fertility in dairy cattle
Authors: Darwash A. O. , Lamming G. E. , Wooliams J. A.
Published: September 2010

The relationship between the interval to post-partum (PP) commencement of luteal activity (CLA) and traditional measures of fertility was studied in 1733 lactations of British Friesian cows. Milk progesterone (P4) concentrations were used to determine the interval to PP ovulation and to confirm pregnancy. Milk samples were taken thrice weekly from cows in 20 commercial herds and daily in the University of Nottingham research herd. Commencement of luteal activity was defined as the day of first PP occurrence ofP4levels >3 μg/l which was then maintained for at least two consecutive readings in the commercial herds and for 4 days in the university herd. Records from animals with retained placenta, uterine infection or those treated with reproductive hormone preparations for reproductive disorders were excluded for this analysis from the original database of cows during 2503 lactations. The interval to PP CLA averaged 27·0 (s.d. 12·1) days (no. = 1733), interval to first service 71·2 (s.d. 19·9) days (no. = 1646), interval to conception 87·2 (s.d. 35·0) days (no. = 1510), number of services per conception 1·50 (s.d. 0·83, no. = 1510) and conception to first service was 0·65. Linear models were then fitted to subsets of the data with complete information to assess the influences of lactation number, season and herd (at least 1243 observations in all analyses). The interval to PP CLA was favourably correlated with measures of fertility such that for every day delay in the interval to CLA there was an average delay of 0·24 and 0·41 days (P < 0·001) in the interval to first service and conception, respectively. The number of services per conception was reduced by 0·11 for each additional 21 days in the interval between PP CLA and first service (P < 0·001). Furthermore, conception rate was influenced by the interval from the onset of luteal activity to first insemination (P < 0·01) such that each additional 21 days progressively reduced the probability of failure at a given insemination number to 0·89 of its previous value. There were significant effects of parity and season (P < 0·05) on the interval to first PP service while the variation among herds in the interval to PP service and days open was significant (P < 0·01). The regressions of measures of fertility on milk yield were not significant. This extensive database on the hormone profiles of PP cows shows that the early re-establishment of PP ovarian activity is an important prerequisite for high fertility.
A measure for predicting genetic merit for milking and nursing ability in beef cattle
Authors: Yokoi N. , Moriya K. , Sasaki Y.
Published: September 2010

To determine a best measure for predicting genetic merit for milking and nursing ability in beef cattle, restricted maximum likelihood (REML) estimates of variances and covariances for direct and maternal effect were obtained by using pre-weaning growth records of calves at various stages after parturition until weaning in Japanese Black cattle. Data used in this study were pre-weaning growth records of 1892 Japanese Black calves obtained from the Tottori National Livestock Breeding Station covering the period from 1960 to 1985. Traits analysed were adjusted monthly weights, adjusted monthly heights and cumulative daily gains (DGs) from birth to 1, 2, 3, 4, 5 and 6 months of age. Estimates of variances and covariances were obtained by REML using the DFREML program of Meyer. Results indicate that: (1) the direct effects on pre-weaning growth of calves are the smallest at birth to 1 month of age and then increase; (2) the maternal effects of the dams are the largest for the first 2 months, and then decrease; (3) the contribution of these two effects on calf growth is reversed at 3 or 4 months of age; (4) the non-additive maternal effects exist but are small; and (5) the genetic correlations between direct and maternal effects are low for weight and cumulative DG, whereas those for height are relatively high. These results suggest that DGfrom birth to 2 months of age (DGO-2) is most influenced by the additive maternal effect. Thus, DGO-2 is concluded to be the best measure for predicting genetic merit for milking and nursing ability in beef cattle.
Renal and salivary clearance of purine derivatives in sheep
Authors: Surra J. C. , Guada J. A. , Balcells J. , Castrillo C.
Published: September 2010

Four adult ewes (mean weight 42·6 kg) fitted with oesophageal fistulae were given 5 mmol/day ofallantoin or saline solutions by intrajugular continuous infusion. The experiment was a randomized cross-over design, with two consecutive 3-day infusion periods. One kg/day fresh matter of either chopped or pelleted fescue hay was distributed over 12 meals and salivary flow estimated from dilution of Co-EDTA infused into the buccal cavity. Allantoin infusion resulted in a rapid increase in its plasma concentration (84 to 128 (s.e. 1·5) μmol/l) and urinary excretion (9·6 to 13·3 (s.e. 0·18) mmol/day) without significant differences between diets. Salivary allantoin also increased (4·6 to 6·4 (s.e. 0·60) ymol/1) in response to infusion, although the concentration of total purine derivatives in saliva was only proportionately 0·08 that of plasma. Renal and salivary clearance of oxypurines, allantoin (78 (s.e. 5·0) ml/min and 13 (s.e. 0·7) ml/h), uric acid (466 (s.e. 98·0) ml/min and 45 (s.e. 9·8) ml/h) and creatinine (104 (s.e. 3·0) ml/min and 14 (s.e. 1·1) ml/h) were constant, irrespective of diet and infusion treatments. Urinary recovery of infused allantoin averaged 0·78 (s.e. 0·031) but salivary secretion, equivalent to about 0·003 of urinary losses, was not the explanation for the incomplete recovery.
The quantitative requirement for α-tocopherol by juvenile African catfish, Clarias gariepinus Burchell
Authors: Baker R. T. M. , Davies S. J.
Published: September 2010

Employing practical-type diets containing graded levels of all-rac-α-tocopheryl acetate (0, 5, 15, 30, 45, 60, 75 or 100 mg/kg), the quantitative requirement for a-tocopherol by juvenile African catfish (Clarias gariepinus Burchell) was investigated. Diets, defined with respect to selenium, fatty acid and ascorbate inclusion, were offered for 12 weeks during which catfish grew from 10 g to 120 g. Dietary regime had no significant effect on growth (P > 0·05), although haematocrit values increased with increasing tocopherol dose above 15 mg/kg (assayed) (R2 = 0·71, P < 0·05). Tissue accretion of the vitamin increased concomitant with dietary dose (P < 0·001). Employing a colorimetric assay for thiobarbituric acid reactive substances (TBARS) it was evident that concentration ofTBARS in muscle and liver reflected tissue oxidation status, in that elevated dietary vitamin E resulted in decreased assayed TBARS (P < 0·05). By broken-line analysis the requirement for this species to suppress lipid peroxidation was estimated as 30 to 40 mg all-rac-a-tocopheryl acetate per kg dry diet and this agrees with published requirements of many fish species.
Photoperiodic effect on live-weight gain of bull calves
Authors: Aharoni Y. , Brosh A. , Holzer Z.
Published: September 2010

The effects of day length, of the daily change in day length and of heat load, together with age effect, on live-weight gain of Holstein-Friesian bull calves, were studied using 8205 gain records of 1019 calves that were maintained in the experimental herd at Newe Ya'ar during a 5-year period (1991 to 1995). The age range of the calves was 150 to 450 days. Effects of day length (h) and of day length change (min/day) were assumed to be linear and effect of age was assumed to be quadratic. Three heat load indexes were calculated, accounting for day temperatures above 27°C, or night temperatures above 18°C, or both, and their effect was assumed to be linear also. Random effect of calf and fixed effect of the year were also accounted for by the regression analysis. The mean gain was 1·274 kg/day. The effect of day length was 0·027 (s.e. 0·003) kg/day per h, and effect of day length change was 0·042 (s.e. 0·003) kg/ay per min/day both effects being highly significant (P < 0·0001). The effects of heat load according to each of the three indexes were either not significant, or tended to be positive, which implies increased gain with increasing heat load. Effect of age was positive (P = 0·0005), and of age2 was negative (P < 0·0001). Based on the regression model that did not include heat load effect, the peak gain was obtained on 19 May, 33 days before the longest day and the trough was obtained on 18 November, with a difference of 0·206 kg/day (proportionately 0·15 of the peak gain) between peak and trough gains. It was calculated by the regression coefficients for the photoperiod effects, that a calf that enters the feedlot at the age of 150 days and a live weight of 180 kg on 1 January, will be 23 kg heavier at the age of 350 days than a calf that enters the feedlot at the same age and weight on 1 July. This difference is reduced to 10 kg at the age of 450 days.
The effect of diet and frequency of watering on the performance of growing cattle given food at maintenance
Authors: Hatendi P. R. , Mulenga F. M. , Sibanda S. , Ndlovu P.
Published: September 2010

An 18-week experiment investigated the effects of type of diet and frequency of watering on the performance of growing cattle given food at maintenance (metabolizable energy (ME) allowance (MJ) = 8·3 + 0·091 M where M = live weight of the animal). Three diets with 20: 80 (low, L), 50:50 (medium, M) and 80: 20 (high, H) roughage to concentrate ratios (10·2, 7·8 and 5·4 MJME per kg dry matter) were used in combination with free access to water for 2·5 h once daily or once every 3rd day. A completely randomized-block design with a 3 (diets) × 2 (watering frequencies) factorial arrangement of treatments was used. Five animals were allocated per treatment (average weight 245 (s.d. 21·6) kg).

Dry-matter intake increased as the roughage content of the diet increased (P < 0·05) but was not affected by the watering regime (P > 0·05). Total water intake was found to be positively correlated with dry-matter intake and increased with dietary roughage level. Animals watered daily drank more (P < 0·05) water (12·6 v. 10·0 kg/day) than those watered every 3rd day. The apparent digestibility of the diets decreased as the amount of roughage increased (diet L 734g/kg, M471 g/kg and H 433 g/kg). Similar apparent digestibilities were observed under the two watering frequencies (546 g/kg and 547 g/kg).

Type of diet significantly (P < 0·05) affected the final weights of the steers. Animals given diet H were proportionately 0·07 heavier than those offered diet L corresponding to total weight changes of −0·8 and +18·4 kg respectively. Carcass weight, backfat thickness and eye muscle area were not affected by the treatments. The chemical composition of the 9 to 11th rib joint was only affected by diet H which gave less fat (P < 0·05). Water, fat, protein and ash content averaged 607,118,190 and 84 g/kg respectively.
Attainment of puberty and response to superovulation in performance-tested Simmental heifers
Authors: Tregaskes L. D. , Broadbent P. J. , Hutchinson J. S. M. , Roden J. A. , Dolman D. F.
Published: September 2010

Puberty during performance test and the effect of reproductive maturity and performance on test on superovulatory response were investigated using Simmental heifers.

Three generations of Simmental heifers (no. = 110) were performance tested for beef characteristics between 23 and 49 weeks of age over 3 years successively. Embryo recoveries were performed at 52 and 61 weeks of age following the end of the performance test. The onset of puberty was observed in 26 of 30 (87%) heifers in the 3rd year. The mean age at puberty was 284·7 (s.e. 6·63) days. Age at puberty was not significantly related to daily live-weight gain (1·5 (s.e. 0·02) kg) up to the onset of puberty. Heifers experienced zero to six oestrous cycles before initiation of the first superovulatory treatments. There was a non-significant tendency (P > 0·05) for heifers that were not cyclic to produce the highest yields of viable and grade 1 embryos at the first embryo recovery.

Performance test characteristics recorded were: total food intake (1604·0 (s.e. 13·2) kg), total energy intake (1852·0 (s.e. 169·0) MJ metabolizable energy) and live-weight gain (263·9 (s.e. 2·2) kg) during test; live weight (486·5 (s.e. 31·5) kg), backfat depth (5·6 (s.e. 15) mm) and muscle score (9·6 (s.e. 0·10) units) at the end of test and estimated breeding value for the selection index (+£7·00 (s.e. 0·76)). These were used as independent variables in general linear models to study their relationship with various measures of superovulatory response. Recovery rate of ova and embryos; and the yields of viable and grade 1 embryos were not related to any aspects of performance on test.

In conclusion, superovulation and embryo recovery were affected by reproductive maturity at the time of gonadotropin treatment and these procedures may be more effective in juvenile heifers before the establishment of cyclicity. Embryo production from 12- to 15-month-old Simmental heifers following a beef performance test was not related to their performance on test.
Ruminal ammonia concentration and energy expenditure of cattle estimated by the carbon dioxide entry rate technique
Authors: Di Marco O. N. , Castiñeiras P. , Aello M. S.
Published: September 2010

Five ruminallyfistulatedAngus steers (360 (s.e. 15·4) kg) were givenfood to maintain body weight constant: maize silage (TO) at 0·6 kg dry matter (DM) per 100 kg body weight twice a day. After a 15-day adaptation period they were infused continuously (I) for 96 h, with a solution of NaH14CO3 at a rate of 7 to 8 micro Curies (μCi) per h. On the last 2 days of infusion 30 g (Tl) and 60 g (T2) urea, respectively, were placed in the rumen at the end of the morning meal. Spot samples of urine (250 ml) were taken before and 5 h after the morning meal and after at least 24 h of infusion. Thereafter, animals continued with TO for one additional week, in which they were prepared with catheters inserted in salivary ducts and infused for 48 h, as previously described. Eighteen pairs of spot samples of urine and saliva were takenfrom three of thefive steers (369 (s.e. 20·7) kg), over a period of 5 h, after at least 24 h infusion (six per animal). Rate of carbon dioxide (CO2) production was estimated as the ratio USA (specific activity of CO2)from which energy expenditure was calculated (22 kj/l CO2). Silage composition, in situ degradability and ruminal ammonia and pH were measured. In situ degradability in thefirst 6 h was 200 g/kg and ruminal ammonia was in the range of 20·6 to 39·6 mg/l. Ammonia increased rapidly to 394·2 (T1) and 673·9 mg/l (T2) 1 h after addition of urea into the rumen but in 6 h in situ degradability was unchanged. Ruminal ammonia decreased linearly at rates (mgll per h) of89·3 in Tl (R2 = 0·57, s.d. = 21·5) and 151·6 in T2 (R2 = 0·81, s.d. = 23·3). Animal energy expenditure rates were not affected (P > 0·05) by treatment (TO = 15·6, Tl = 15·6 and T2 = 15·8 kj/h per M075). There was no difference (P > 0·05) in CO2 production rate (mllh per kg M0·75) determined from the SA of CO2 from urine (604) or saliva (630) samples. It was concluded that the energy cost associated with detoxification of the excess of ruminal ammonia was of minor importance in terms of total animal energy expenditure and that estimations ofC02 ratesfromsamples ofurine or saliva are comparable.
The effect of nutrition on the periparturient parasite status of mature ewes
Authors: Donaldson J. , van Houtert M. F. J. , Sykes A. R.
Published: September 2010

The rôle of nutrition in the periparturient breakdown of resistance to gastrointestinal parasitism in mature ewes was investigated. Host resistance around this period, as measured by faecal egg concentration and worm burden, was sensitive to protein supply and to a lesser extent energy supply and body condition. Resistance was significantly less in ewes bearing and suckling twin lambs than those with singles. Differences in larval intakes spanning the range likely to be experienced in practice did not appear to be important. In dual infection with Teladorsagia circumcincta and Trichostrongylus colubriformis, the breakdown of resistance occurred almost exclusively with T. circumcincta confirming previous evidence of parasite species specificity in the periparturient breakdown of resistance.
Effect of sex on meat quality of Spanish lamb breeds (Lacha and Rasa Aragonesa)
Authors: Horcada A. , Beriain M. J. , Purroy A. , Lizaso G. , Chasco J.
Published: September 2010

The influence of sex on the meat quality of Lacha (L) and Rasa Aragonesa (RA) lambs was studied. Male and female L lambs were given ewes' milk and were slaughtered at 25 and 24 days of age corresponding to 11·4 and 10·9 kg live weight (LW), respectively. Male and female RA lambs were weaned at 58 days (16·0 kg LW) and then given concentrate and barley straw until slaughter at 89 and 91 days of age, corresponding to 24·5 and 23·1 kg LW, respectively. The parameters measured on the carcasses were: hot carcass weight, cold carcass weight, conformation, colour, firmness and thickness of dorsal fat and colour of muscle rectus abdominis. Parameters measured on longissimus dorsi muscle were: ultimate pH (pHu), instrumental colour (L*, a*, b*), myoglobin concentration, ash, crude protein, fat, moisture and water-holding capacity (WHC). Iodine value and fatty acid composition were studied in the intramuscular (IM), intermuscular (IN) and subcutaneous (SC) fat depots. Females of both breeds had higher amount of IM fat (P < 0·001 and P < 0·05 for L and RA breeds, respectively) and firmer SC fat than males (P < 0·05). There were no differences between sexes in pHu, myoglobin concentration, WHC and the L*, a* and b* colour parameters. No significant differences between sexes were observed in the total saturated fatty acids, total unsaturated fatty acids and in the iodine value in the three fat depots studied in both breeds. However, the females of the breed had significantly higher proportions offatty acids with 15 carbon atoms (pentadecanoic (C15:0)) and with 16 carbon atoms (palmitic (C16:0)and palmitoleic (C16:1)) than the males in the three depots. The females of Rasa Aragonesa breed had a higher proportion of palmitoleic acid (C16:1)in the IM depot (P < 0·001) and of palmitic acid (C16:0)in the SC depot (P < 0·05) than the males. The absence of significant differences in the unsaturated fatty acid content between males and females showed that at the low slaughter weight, sex had no effect on the nature and composition of fat.
Feeding value of pea (Pisum sativum, L.) 2. Nutritional value in the pig
Authors: Grosjean F. , Bastianelli D. , Bourdillon A. , Cerneau P. , Jondreville C. , Peyronnet C.
Published: September 2010

Nineteen round white-feed peas (FP) varieties, six coloured-flowered peas (CP) varieties and four wrinkled white-flowered peas (WP) varieties were given to growing pigs in order to measure their feeding value. Mean values of energy apparent digestibility measured at the faecal level of FP, CP and WP were respectively 0·886, 0·812 and 0·823. Mean values for digestible energy were 16·34, 1506 and 15·60 M]l kg dry matter. Mean values of faecal apparent digestibility of protein were 0·840, 0·760 and 0·828. The lower energy and crude protein (CP) apparent digestibility of CP relative to FP can be explained by their higher fibre content and by the presence of condensed tannins whilst the lower energy and CP apparent digestibility in WP relative to FP can be explained by their higher fibre content, their lower starch content and their higher amylosel amylopectine ratio. Among the feed peas, there was no difference between peas with low trypsin inhibitor activity and peas with medium trypsin inhibitor activity.
Effect of intermittent light regimens on the performance of intact male turkeys
Authors: Lewis P. D. , Perry G. C. , Sherwin C. M.
Published: September 2010

An 8-h photoperiod, compared with 12-, 16- or 23-h photoperiods, has been shown to reduce the incidence of injurious pecking and leg problems in intact male turkeys but to result in lower body weights, slower sexual development and less efficient food conversion. The effect of 8 h of illumination given as a solid photoperiod, as eight 1-h periods equally spread through the 24 h or concentrated into a 12-h part of the day on the performance of BUT 8 intact male turkeys was investigated.

Fragmentation of the daily illumination increased body weight, improved food conversion efficiency but did not significantly affect food intake. Increased sexual displaying and significantly better food conversion between 16 and 20 weeks by the two intermittently illuminated groups strongly suggested that both regimens were interpreted as stimulatory daylengths. Generally, losses due to mortality and culling were higher in both fragmented groups, while injurious pecking was higher in 8(1L: ID) birds before 5 weeks and in birds given a 12-h ‘subjective day’ after 5 weeks than in 8-h controls. Culling due to leg problems was significantly higher in birds on the 8(1L:2D) regimen but the incidence of leg imperfections was minimal (< 0·037) in all groups. Both intermittent groups but the 8(1L: 2D) in particular, showed a reduced response to hand movement across the eyes compared with 8-h controls. The controls ate proportionately more food during their 16-h dark period than did the intermittent group during their 12-h ‘subjective night’, though both groups increased their ‘nocturnal’ feeding with age.
Sozioökonomische Unterschiede im Substanzkonsum von Jugendlichen
Authors: Richter Matthias , Hurrelmann Klaus
Published: September 2010

Fragestellung: Der Beitrag geht der Frage nach, ob der Konsum psychoaktiver Substanzen im Jugendalter mit dem sozioökonomischen Status der Eltern und dem Schultyp der Jugendlichen variiert.

Methodik: Die Daten stammen aus dem deutschen Teil der internationalen WHO-Studie »Health Behaviour in School-aged Children«, in der 5.650 Schulkinder im Alter von 11 bis 15 Jahren im Jahr 2002 befragt wurden.

Ergebnisse: Während der Berufsstatus der Eltern und der familiäre
Wohlstand nur einen schwachen Einfluss auf den Substanzkonsum von
Jugendlichen aufweisen, steht der
Schultyp in einer engeren Beziehung
zum Tabak-und Alkoholkonsum. Für
den Cannabiskonsum konnten weder
sozioökonomische noch schulformspezifische Unterschiede nachgewiesen werden.

Schlussfolgerungen: Die
Ergebnisse weisen darauf hin, dass präventive Maßnahmen, die auf eine
Reduzierung aktueller ebenso wie späterer gesundheitlicher Ungleichheiten
abzielen, verstärkt im schulischen Kontext – insbesondere in den Haupt- und Realschulen – zu implementieren sind.
Substitution mit oder ohne Behandlungsvertrag? Eine Untersuchung von Substitutionsfällen im kleinstädtischen und ländlichen Raum
Authors: Zitzmann Reiner , Weiler Detlef
Published: September 2010

Ziel: Diese Untersuchung verfolgt die Frage, ob eine vertraglich geregelte Substitutionsbehandlung erfolgreicher ist als eine ohne Behandlungsvertrag.

Methodik: Es handelt sich um eine retrospektive Analyse von 186 standardisiert dokumentierten Behandlungsfällen. Für die Überprüfung der Frage, ob sich Patienten mit oder ohne Vertrag bezüglich einiger Erfolgskriterien unterscheiden, wurde der Chi2-Test eingesetzt. Veränderungen der körperlichen und psychischen Situation wurden mit dem Wilcoxon-Test überprüft.

Ergebnisse: Günstigere Ergebnisse erzielen die Patienten mit Vertrag vor allem bei der psychischen Stabilisierung und bei Verbesserungen in
den Bereichen Wohnung, Partnerschaft, Freizeit und Tagesstrukturierung.

Schlussfolgerungen: Die im
Behandlungsvertrag festgelegten Absprachen zur psychosozialen Betreuung führen zu einer intensiveren und erfolgreicheren Arbeit mit den Substituierten.
Drogen als Ursache für Verkehrsunfälle, im Fokus: Cannabis
Authors: Kauert Gerold , Iwersen- Bergmann Stefanie
Published: September 2010

Fragestellung: Die Unfallumstände von 108 Verkehrsunfällen, mit dem Nachweis psychoaktiver Substanzen im Blut des schuldhaften Verursachers wurden mit der Fragestellung ausgewertet, ob es Zusammenhänge zwischen Drogentyp, -konzentration und Unfallumständen gibt.

Methodik: Es standen der toxikologische Blutbefund und die Ermittlungsakten der Staatsanwaltschaft zur Auswertung zur Verfügung. Aus den Rohdaten wurden klassifizierte Merkmale gebildet.

Ergebnisse: Die Cannabis-Unfälle stellten die größte Gruppe unter den Einzeldrogen, wiesen am häufigsten unauffällige körperliche Befunde und gleichzeitig die schwersten Unfallfolgen auf.

Schlussfolgerungen: Die Auswertung zeigt, dass Cannabis im Zusammenhang mit der Teilnahme am Straßenverkehr keineswegs als »weiche« oder »harmlose« Droge eingestuft werden kann.
Virale Hepatitis und HIV aus der Sicht von Drogenkonsumentinnen
Authors: Brodbeck Jeannette , Matter Monika , Roos Markus , Moggi Franz
Published: September 2010

Fragestellung: Analyse von Ansatzpunkten für die HBV/HCV-Präventionsempfehlungen für das sexuelle Risikoverhalten von Drogenkonsumentinnen.

Methodik: Einschätzungen zu HBV/HCV und HIV von 146 Befragten wurden verglichen und ihr Zusammenhang mit dem sexuellen Risikoverhalten analysiert.

Resultate: HBV/HCV-Infektionen wurden als weniger schwerwiegend eingeschätzt und die Schutzmotivation und der Wissensstand bezüglich HBV/HCV waren geringer ausgeprägt als bei HIV. Personen mit geringerer Selbstwirksamkeit, Schutzmotivation und geringerem Wissen hinsichtlich HBV/HCV hatten häufiger sexuelles Risikoverhalten.

Schlussfolgerungen: Selbstwirksamkeit und Schutzmotivation sind Ansatzpunkte für die HBV/HCV- und HIV-Prävention. Für HBV/HCV muss zudem das Problembewusstsein erhöht und der Wissensstand verbessert werden.
Psychiatrische Begutachtung bei problematischem Spielverhalten
Authors: Bork Stephan , Foerster Klaus
Published: September 2010

Die Arbeit gibt einen Überblick über die Grundzüge der forensisch-psychiatrischen Begutachtung bei problematischem Spielverhalten. Die nosologische Konzeptualisierung des Krankheitsbildes pathologisches Glücksspiel wird problematisiert und die Diagnosekriterien nach ICD-10 und DSM-IV-TR werden erläutert. Es folgt eine eingehende Auseinandersetzung mit den psychopathologischen Voraussetzungen die aus unserer Sicht erfüllt sein müssen, um pathologisches Glücksspiel einer de- bzw. exkulpierenden juristischen Merkmalskategorie zuordnen zu können. Zur darauf aufbauenden forensisch-psychiatrischen Beurteilung der Steuerungsfähigkeit werden konkrete Hinweise gegeben. Abschließend werden die therapeutischen Möglichkeiten und deren Erfolgsaussichten kurz zusammengefasst.
Testung eines Erklärungsmodells zur Nikotinabhängigkeit und zum Zigarettenkonsum bei arbeitslosen Metallarbeitern
Authors: Puls Wichard , Inhester Marie-Luise , Wienold Hanns
Published: September 2010

Fragestellung: Zwischen Arbeitslosigkeit und dem Konsum von Tabak ist in zahlreichen Studien ein Zusammenhang nachgewiesen worden. Peirce et al. (1994) haben ein Erklärungsmodell vorgelegt, das die Beziehungen zwischen Stressoren, emotionalen Auswirkungen dieser Stressoren und dem Konsum von psychotropen Substanzen beinhaltet. Methodik: In einer Längsschnittuntersuchung wurde dieses Modell getestet, in dem arbeitslose Metallarbeiter zu psychosozialen Belastungen und zum Konsum von Zigaretten befragt wurden (n=223). Die Auswertung erfolgte mittels pfadanalytischer Methodik (LISREL) und multipler Regressionsanalysen. Ergebnisse: In dem Modell dominiert der Einfluss individueller Ressourcen (Selbstvertrauen) auf depressive Verstimmungen und Rauchmotivationen, während die Stressoren der Lebensumwelt der Arbeitslosen (fehlende soziale Unterstützung, soziale Konflikte und finanzielle Belastungen) von geringer Bedeutung sind.Schlussfolgerungen: Die Motivation, Zigaretten zur Stressbewältigung einzusetzen bzw. der Zigarettenkonsum und die Nikotinabhängigkeit werden – anders als in dem Modell von Peirce et al. (1994) angenommen – kaum von Emotionen beeinflusst, die als Folge der Arbeitslosigkeit zu sehen sind.
Gibt es einen Delinquenzrückgang durch soziale Reintegration im Rahmen der schweizerischen Heroinverschreibungsversuche?
Authors: Ribeaud Denis
Published: September 2010

Ziel: In der vorliegenden Studie wird überprüft, ob die im Rahmen der heroingestützten Behandlung festgestellte Abnahme der Delinquenz auf individueller Ebene mit der Entwicklung von Indikatoren zur sozialen Lage und zum Suchtverhalten einhergeht. Methodik: Basierend auf einer einheitlichen Stichprobe wird überprüft, ob dieselben Entwicklungstrends festgestellt werden können wie in den bisherigen Untersuchungen. Dabei können die früheren Befunde weitgehend repliziert werden. Alsdann wird die Kernthese mittels bivariater logistischer Regressionen untersucht. Ergebnisse: Die Delinquenzabnahme geht zwar mit einer Desintegration aus der Drogensubkultur, nicht aber mit einer gesellschaftlichen Reintegration einher. Im Wesentlichen lässt sie sich mit dem verringerten finanziellen Bedarf erklären. Schlussfolgerungen: Praktische und theoretische Implikationen der Ergebnisse werden unter Berücksichtigung der Befunde neuerer Untersuchungen zu den Langzeitwirkungen der Heroinverschreibung diskutiert.
A quality framework for addiction treatment programmes: Results of a concept mapping strategy
Authors: Nabitz Udo , van den Brink Wim , Walburg Jan
Published: September 2010

Ein Qualitätsrahmen für Suchtbehandlungsangebote: Ergebnisse einer Concept Mapping Strategie

Ziel: Empirische Identifikation von Qualitätskriterien, -clusters und -dimensionen für Programme der Suchtbehandlung. Methode: Drei Interessengruppen (Stakeholders N=90) generierten 667 Ideen, die zu 70 Statements zusammengefasst und mit mulitivariaten statistischen Techniken analysiert wurden. Ergebnisse: Neun Cluster mit zwei Dimensionen »Best Practice« und »Effektivität« wurden identifiziert. Die drei wichtigsten Qualitätscluster waren »Klientenorientierung«, »Behandlungsangebot« und »Einstellung der Behandler«. Die drei wichtigsten Statements waren: »Effektivität des Programms«, »respektvolle Interaktion mit dem Patienten« und »leichter Zugang zu den Behandlungsangeboten«.
Schlussfolgerungen: Der empirisch abgeleitete Qualitätsrahmen für Suchtbehandlungsangebote ist spezifisch und umfassend. Es zeigen sich Übereinstimmungen und Ergänzungen zu bestehenden Zertifizierungs- und Qualitätssicherungssystemen.