bluuebunny/crossref_metadata_2025 huggingface dataset:
Water intake and excretion, urinary solute excretion and some stress
indicators in mink (Mustela vison): 1. Effect of ambient temperature and
quantitative water supply to adult males
Authors: Tauson A.-H.
Published: August 2016

Thermal environment and water supply are factors which are supposed to
influence the performance and well being of farm-raised mink but conclusive
literature data are still very limited. The present series of experiments was
conducted in order to quantify effects of thermal environment on water intake and
excretion, urinary solute excretion and estimate possible stress reactions. Water
intake and excretion, urinary osmolality and urinary excretion of sodium (Na),
potassium (K), cortisol and catecholamines were studied in a balanced Latin-square
design experiment with six adult male mink, kept at three different ambient
temperatures (Ta); (5°C, 20 °C and close to 35 °C) and given
three different water supplies (E: extra water in the food; N: normal ad libitum
drinking water supply; R: restricted, free access to drinking water twice daily).
The experiment comprised nine periods, each of 3 days. Food apparent
digestibility, intake of metabolizable energy (ME), metabolic and evaporative
water, oxidation of nutrients and ME requirement for maintenance
(MEm) were calculated. Water intake was strongly affected
by Ta, with dietary water being the major source at 5°C and
20 °C, its importance being profoundly exceeded by drinking water at 35 °C. Water
excretion in urine was highest at the lowest Ta and lowest at
the highest Ta. Restriction of access to drinking water
resulted in lower total water intake, and excretion, mainly by decreased urinary
volume, reflected by increased urinary osmolality and increased solute
concentration. ME intake decreased as Ta increased but
urinary and total water output per kJ ME was not significantly affected by
Ta or water supply. Excretion of Na and К per kJ ME mainly
monitored urinary water excretion, being highest under conditions when urine
production was highest. Metabolic water made up 0·14 to 0·17 of the total water
intake and evaporative loss increased from about 50 to 125 g/kg live weight
(M)0·75 as Ta increased.
MEm was lowest (534 kJ/kg M0·75) at
20 °C, and highest (647 kJ/kg M0·75) at 35 °C. Cortisol
excretion generally tended to increase when water supply was restricted, the
increase being significant at 35 °C. This, in combination with outer signs of
distress in the animals, emphasized that this high temperature in combination with
limited access to drinking water exposed the animals to a very stressful situation
but rectal temperature remained normal, indicating intact temperature regulation
mechanisms.
Genetic and epidemiological relationships between productivity and disease resistance: gastro-intestinal parasite infection in growing lambs
Authors: Bishop S. C. , Stear M. J.
Published: August 2016

This paper demonstrates how interactions between host genotype for resistance to an infectious disease and the epidemiology of that disease can have large influences on animal productivity and hence on breeding goals for domestic livestock. This is illustrated for the case of gastro-intestinal parasitism in lambs. A model of the parasite infection was developed to include between-animal variation (genetic, permanent and temporary environmental) for live-weight gain, food intake, larval establishment rate in the host, worm fecundity and worm mortality rate. Achieved live-weight gain was defined as the sum of potential live-weight gain under conditions of no parasite infection, a trait correlated with food intake and growth-rate reduction due to the infection. The reduction in growth-rate was calculated from cumulative larval challenge and cumulative worm mass in the lamb. Genetic parameters were then estimated for the output traits of observed live weight at 6 months of age, growth rate reduction and faecal egg count. Model parameters were chosen so that the output means and heritabilities for faecal egg count and live-weight gain mimicked field data for Scottish Blackface lambs and growth-rate reductions were proportionately 0·25 , on average. The model predicted a weak phenotypic correlation (mean = -0·10) between observed live weight and faecal egg count, the indicator of resistance but a stronger favourable (negative) genetic correlation between these traits (mean = -0·27). The severity, or epidemiology, of the disease greatly influenced the results - the genetic correlation between observed live weight and faecal egg count strengthened from -0·02 to -0·46 as the disease severity changed from mild to severe. Selection for reduced faecal egg count resulted in large correlated increases in live-weight gain, more than twice that predicted by quantitative genetic theory, due to the reductions in growth rate losses as the disease challenge to the animals decreased. Conversely, selection for increased live-weight gain resulted in reductions in faecal egg count close to expectations. This asymmetry of selection response emphasizes the epidemiological benefits obtainable from selection for resistance to infectious chronic diseases - such selection will result in improvements in both animal health and productivity not seen when selection is for improved productivity, alone. Breeding goals should be designed to take account of such effects.
The effects of synchronizing the rate of dietary energy and nitrogen supply to the rumen on the metabolism and growth of ram lambs given food at a restricted level
Authors: Witt M. W. , Sinclair L. A. , Wilkinson R. G. , Buttery P. J.
Published: August 2016

The effects of diets formulated to have two rates of organic matter (OM) release and to be either synchronous or asynchronous with respect to their hourly release of OM and nitrogen (N) in the rumen on N retention, microbial N production, growth and metabolism of ram lambs offered food at a restricted level was studied in two experiments. Four diets were formulated to differ in their rate and extent of OM and N release in the rumen based on the sum of in situ degradability data of the ingredients. All diets were formulated to have a similar metabolizable energy (10·4 MJ/kg dry matter (DM)), crude protein (140 g/kg DM) and daily ratio of N : OM released (34 g N per kg OM) and were either synchronous or asynchronous with respect to their hourly N : OM release. The four diets were slow energy, synchronous (SS), slow energy asynchronous (SA), fast energy, synchronous (FS) and fast energy asynchronous (FA). In both experiments the diets were offered at a rate of 1·75 maintenance energy requirements as two equal meals at 09:00 and 17:00 h. In experiment 1 there was no significant effect of diet on OM apparent digestibility or N retention. Lambs given diet FS had the highest daily production of allantoin (7·82 mmol per day; P < 0·05) and microbial N (7·80 g/day; P < 0Ό5). Hourly plasma urea and ß-hydroxy butyrate (3-OHB) concentrations exhibited a cyclical trend between meals with maximum concentrations occurring within 3 h of feeding and were higher in lambs given diet FA.

In experiment 2 the four diets were offered to 32 growing ram lambs. Animals given synchronous diets (SS and FS) had a significantly higher live-weight gain than those given asynchronous diets (SA and FA; (132 g/day v. 107 g/day respectively; P < 0·001). Food conversion efficiency (FCE; kg gain per kg DM intake) was improved proportionately by 0·23 in animals offered synchronous diets compared with asynchronous diets (P < 0·001). There was little effect of diet on carcass composition except kidney fat, which was greater in lambs offered the synchronous diets (P < 0·01). Plasma 3-OHB concentrations were higher throughout the growth period in lambs given diet FA whilst plasma urea concentrations were greater in lambs given the diet SS. In conclusion, greater attention to the formulation of diets to be synchronous for their hourly release of N : OM in the rumen can improve the growth rate and FCE of lambs. This effect may be due to an improvement in energy rather than N metabolism.
The use of cumulative gas production technique to characterize changes in the fermentation characteristics of rumen contents following variable periods of starvation and grazing in dairy cows
Authors: Chilibrostet P. , Williams B. A. , Tamminga S. , Calabro S.
Published: August 2016

The effect of the duration of grazing (experiment 1) and starvation time and placement in the rumen of inert bulk material before grazing (experiment 2), on the rumen content ferment ability, was investigated by means of measuring cumulative gas production. In experiment 1, a comparison was made of four durations of grazing (1, 1·75, 2·50 and 3·25 h) after overnight starvation. Rumen samples taken from the cows after 1 h of grazing had higher values of total accumulated gas with less (P < 0·05) time required to reach the maximum fermentation rate than cows grazed for 3·25 h. Following grazing, a 7·75·h starvation period was imposed on the four treatments. The extent of fermentation was significantly lower (P < 0·01) after starvation than immediately after grazing (49·7 v. 60·8% of incubated dry matter (DM), respectively). Experiment 2 consisted of a factorial combination of two durations of starvation before grazing (16·5 (LS) and 2·5 (SS) h) with the presence or absence in the rumen of 12·5 kg of a synthetic indigestible material. Before grazing the total accumulated gas production was less (P < 0·05) for the LS than for the SS cows. After the grazing session, the total gas of rumen samples from the LS cows was significantly higher (P < 0·05) than for the SS cows.

This was in agreement with the observed higher DM intake during grazing and DM rumen pools after grazing in LS cows. For both starvation periods, the presence of inert rumen bulk led to a higher total gas, a shorter half-time and less DM left unfermented. The measurement of fermentation kinetics by cumulative gas production was suitable to detect changes in rumen content fermentation patterns due to the clearance of material from the rumen (effect of starvation) or DM intake during the grazing sessions.
Selection with control of inbreeding in populations with overlapping generations: a comparison of methods
Authors: Sonesson A. K. , Grundy B. , Woolliams J. A. , Meuwissen T. H. E.
Published: August 2016

Methods that maximize genetic response in populations with overlapping generations while controlling rate of inbreeding by constraining the average relationship among selection candidates were compared. Firstly, computer simulations of closed nucleus selection schemes showed that a two-stage optimization algorithm approach, where the distribution of parents within and thereafter over age classes was optimized resulted in different breeding schemes than an approach that performed an iteration on this distribution. It yielded significantly lower annual genetic gain (0·194 v. 0·223 σpunits), fewer animals selected (21·9 v. 26·4) and longer generation intervals (2·38 v. 1·68 years) but maintained the rate of inbreeding closer to its constraint. In large schemes, iteration may be computationally the only feasible method for the optimization of parents across age classes. Secondly, the use of conventional relationships for constraining inbreeding was compared with that of augmented relationships, which do not depend on the level of inbreeding. Both relationships resulted in very similar breeding schemes, but the use of augmented relationships avoids correction of the current level of inbreeding. Thirdly, a constraint of the rate of inbreeding on a per year basis was compared with a constraint on a per generation basis. When optimizing per generation, the generation interval was shorter compared with a scheme where an analogous annual restriction was in place (2·01 v. 2·38 years) and the annual rate of genetic gain was higher (0·214 v. 0·194 σpunits).
Growth and carcass characteristics of three lamb genotypes finished on the same level of feeding
Authors: McClintont L. O. W. , Carson A. F.
Published: August 2016

This study investigated the efficiency of growth and the carcass characteristics of 24 Greyface (Border Leicester × Scottish Blackface), 24 Texel (12 purebred and 12 Texel × Texel-Greyface) and 24 Rouge (12 purebred and 12 Rouge × Rouge-Greyface) lambs finished on the same level of feeding. The efficiency of live-weight gain (kg/MJ) was higher in Greyface compared with Texel lambs (P< 0·01). The efficiency of empty body-weight gain (kg/MJ) was higher in Greyface (P< 0·01) and Rouge (P< 0·05) compared with Texel lambs. The efficiency of carcass gains (kg/MJ) tended to be higher in Greyface and Rouge compared with Texel lambs (P= 0·07). The efficiency of non-carcass component gains (kg/MJ) was also higher in Greyface compared with Texel lambs (P0·05). Carcass water, protein, lipid and ash gains did not vary significantly between the genotypes, however carcass energy gain tended to be higher in Greyface and Rouge compared with Texel lambs (P= 0·08). The relative proportions of water, protein, lipid and ash in carcass gains did not vary significantly between the genotypes. At the end of the experiment carcass water content was higher in Texel compared with Greyface lambs (P< 0·05) and carcass ash content was lower in Texel compared with Greyface (P< 0·01) and Rouge (P< 0·05) lambs. The concentration of saturated fatty acids was higher in Greyface compared with Rouge lambs (P< 0·001) and higher in Rouge compared with Texel lambs (P< 0·05). Monounsaturated fatty acid concentrations were higher in Rouge compared with Greyface lambs (P< 0·05) and higher in Texel compared with Rouge lambs (P< 0·001). Polyunsaturated fatty acid concentrations were higher in Rouge and Texel compared with Greyface lambs (P< 0·01). The ratio of n-6:n-3 fatty acids was lower in Rouge compared with Greyface lambs (P< 0·05).

The efficiency of empty body gain was higher in male compared with female lambs (P< 0·05). Carcass water (P< 0·01) and protein (P< 0·05) gains were higher in male lambs. At the end of the experiment male carcasses contained a higher content of water (P< 0·05), protein (P< 0·01) and ash (P= 0·07), and a lower lipid (P< 0·05) and energy (P< 0·001) content. Carcass lipids from male lambs contained a higher concentration of polyunsaturated fatty acids (P< 0·001) and tended to contain a lower concentration of saturated fatty acids (P = 0·06).
Effects of cow families on type traits in dairy cattle
Authors: Roughsedge T. , Brotherstone S. , Visscher P. M.
Published: August 2016

The component of variance attributable to maternal lineage for type traits in the UK Holstein Friesian dairy population was estimated. First lactation type classification records of 33 325 contemporary cows, classified between 1996 and 1998 were used in the analysis. Maternal pedigree records were traced back to 1960 to establish maternal lineages. The tracing resulted in cows being assigned to 10 332 cow families with more than one cow per family. Sixty-six percent of the cows were in families of less than five. The traits comprised 16 linear type traits, a total score trait, four composite scores and measures of temperament and ease of milking. Univariate analysis of each trait was performed using residual maximum likelihood, with and without a maternal lineage component. A principal component analysis used a scree test to determine the number of independent traits being considered in-order to establish a level of significance for the test statistic. It was found that eight principal components were responsible for the variation in type. The composite body score trait was found to have a 1·5% component of maternal lineage variance, significant at the 5% level. No other traits showed a significant maternal lineage variance component.
Estimates of genetic parameters for growth and skeletal measurements in Thai swamp buffalo
Authors: Meyer K. , Graser H. -U. , Na-Chiangmai A.
Published: August 2016

Estimates of genetic parameters were obtained for weight, hip height, heart girth and shoulder to pin length measurements on Thai swamp buffalo, recorded at birth and weaning. Direct heritability estimates were 0·26 for weights at both ages and were low for skeletal measurements, ranging from 0·11 to 0·19. Low values could, in part at least, be caused by inaccuracies in recording. All traits were subject to maternal effects, permanent environmental maternal effects on traits recorded at weaning explaining proportionately up to 0·14 of the total variation. Estimates of genetic (direct and maternal) and permanent environmental correlations between traits recorded at the same time were high throughout, ranging from 0·83 to 0·97 for additive genetic effects and being close to unity otherwise. Except for heart girth measured at weaning, there appeared to be comparatively little genetic association between traits recorded at different times, direct additive correlation estimates ranging from 0·18 to 0·55 in contrast to estimates of 0·38 to 0·65 for correlations with heart girth at weaning.
Genetic modelling of daily milk yield using orthogonal polynomials and parametric curves
Authors: Brotherstone S. , White I. M. S. , Meyer K.
Published: August 2016

Random regression models have been advocated for the analysis of test day records in dairy cattle. The effectiveness of a random regression analysis depends on the function used to model the data. To investigate functions suitable for the analysis of daily milk yield, test day milk yields of 7860 first lactation Holstein Friesian cows were analysed using random regression models involving three types of curves. Each analysis fitted the same curve to model overall trends through a fixed regression and random deviations due to animals. Curves included orthogonal polynomials, fitted to order 3 (quadratic), 4 (cubic) and 5 (quartic), respectively, a three-parameter parametric curve and a five-parameter parametric curve. Sets of random regression coefficients were fitted to model both animals’ genetic effects and permanent environmental effects. Temporary measurement errors were assumed independently but heterogeneously distributed, and assigned to one of 12 classes. Results showed that the measurement error variances were generally lowest around peak lactation, and higher at the beginning and end of lactation. Parametric curves yielded the highest likelihoods, but produced negative genetic associations between yield in early lactation and later lactation yields, while positive genetic correlations across the entire lactation were estimated with all models involving orthogonal polynomials. The fit of models using orthogonal polynomials to model test day yield was improved by including higher order fixed regressions.
The flexibility of feeding patterns in individually housed pigs
Authors: Bornett H. L. I. , Morgan C. A. , Lawrence A. B. , Mann J.
Published: August 2016

Group-housed pigs may be prevented from expressing their desired feeding pattern by more dominant individuals in the group. Indeed, when compared with individually housed pigs, group housed pigs eat less frequent, but larger meals. Therefore, it would be advantageous for pigs to have flexible feeding patterns in order to decrease the impact of group housing. The aim of this study was to assess the flexibility of feeding patterns by restricting the time of access to food of pigs previously given food ad libitum and then returning them to 24-h access. Thirty-two Large White x Landrace pigs were used in an experiment of two blocks (16 pigs per block) each comprising three, 2-week periods. In each block; during period 1, all pigs were allowed 24-h access to food after which, in period 2, eight of the pigs had access to the feeder restricted between 11:00 and 13:00 h of each day. The remaining eight pigs continued on 24-h access to food and acted as controls. In period 3, all pigs were again returned to 24-h access to food. Daily feeding pattern and food intake were recorded throughout. Behavioural observations in the form of scan samples were made and pigs were weighed twice a week. In period 2 the restricted pigs had fewer visits to the feeder per day, 34·0 v. 70·1 (P < 0·001); of a longer duration, 98·3 v. 64·5 s (P < 0·01); with a higher food intake per visit, 64·9 v. 33·3 g (P < 0·001) than the control pigs. Daily food intake and live-weight gain were lower (P < 0·001) for the restricted pigs in period 2 than for the control pigs. Restricted pigs spent more time rooting (P < 0·05), and less time sleeping (P < 0·05) than the control pigs in period 2. In addition, there was a trend for pigs to spend more time alert in the observation session prior to access to food in the second period when they were restricted and they made attempts to gain access to the feeders in this session. An indication of flexibility was gained by comparing feeding behaviour and time budgets between periods 1 and 3. The pigs that experienced a period of restricted feeding either resumed their previous behaviour or showed the same trend as the controls. In periods 1 and 3 daily feeder visits were 66·2 and 68·1 for control pigs, and 65·6 and 67·1 for restricted pigs. Mean durations of visits were 79·3 and 47·5 s, and 74·4 and 61·7 s respectively. It was concluded that feeding behaviour was flexible and time budgets were resilient across periods.
Choices by lactating cows between concentrates high or low in digestible undegraded protein
Authors: Lawson R. E. , Redfern E. J. , Forbes J. M.
Published: August 2016

To determine whether lactating cows select a nutritionally appropriate diet when given grass silagead libitumand a choice of concentrates high or low in digestible undegradable protein (DUP), 24 mid-lactation Holstein-Friesian cows were given, in different 3-week periods, a concentrate high in DUP (HP), one low in DUP (LP), or a choice between the two (CHOICE), all at an allowance of 5·4 kg dry matter per day. Milk yield was significantly lower, and silage intake slightly but significantly higher, on LP than on either HP or CHOICE. The mean proportion of HP taken in the CHOICE period was 0·47 which was greater than the proportion required to satisfy the cows’ calculated requirements for effective rumen degradable protein, DUP or metabolizable protein but not significantly different from the ratio of 0·50 expected if no choice was made. Individual cows had a strong tendency initially to continue to eat from the feeder from which they had obtained concentrates in the period before CHOICE but this changed to eating significant amounts of both foods within about a week. The fact that the relationship between the proportion of HP in the concentrate intake and milk protein output was significant and positive, and became more so as the CHOICE period progressed, supports the hypothesis that protein demand was directing diet selection but must be viewed with caution as it was heavily influenced by the results of one animal: the highest-yielding cow which also chose to eat the greatest proportion of HP.
Dietary choline requirement of juvenile grass shrimp (Penaeus monodon)
Authors: Shiau S. Y. , Lo P. S.
Published: August 2016

A feeding trial was conducted to determine the dietary choline requirement of juvenile grass shrimp, Penaeus monodon. Purified basal diets were formulated using vitamin-free casein (containing 370 mg choline per kg) as the protein source. Graded levels (0, 300, 600, 1000, 2000, 4000, 7000, and 10 000 mg choline per kg diet) of choline chloride were added to the basal diet, resulting in eight dietary treatments in the experiment. Each diet was given to three replicate groups of shrimp initially averaging 1·18 (s.d. 0·01) g for 8 weeks. Weight gain was highest in shrimp given the diets supplemented with 7000 and 4000 mg choline per kg diet, followed by the groups given 2000 mg/kg, then 1000 and 600 mg/kg, and finally 300 mg/kg and the unsupplemented control group (P < 0·05). Shrimp given diets supplemented with 7000 and 4000 mg choline per kg diet had significantly higher food efficiency and survival than those given diet with 300 mg choline per kg or the control diet. Higher body crude protein and choline concentrations were recorded in shrimp given diets supplemented with 4000 and 7000 mg choline per kg diet than shrimp given diets with ≤600 mg choline/kg and ≤2000 mg choline per kg, respectively. Analysis by polynomial regression of weight gain and body choline concentration for P. monodon gave a maximum at about 6000 mg/kg. Taking into account the choline concentration of the unsupplemented basal diet, the optimal dietary choline requirement for growing P. monodon is about 6200 mg/kg.
Re-evaluation of the vitamin E requirements of juvenile tilapia (Oreochromis niloticus ✕ O. aureus)
Authors: Shiau S. Y. , Shiau L. F.
Published: August 2016

A 10-week feeding trial was conducted to re-evaluate the level of dietary vitamin E (DL- α-tocopheryl acetate) that was adequate for juvenile tilapia Oreochromis niloticus ✕ O. aureus given diets containing two dietary lipid concentrations. Purified diets with eight levels of vitamin E (0, 25, 50, 75, 100, 150, 200, 400 mg/kg diet) at either 50 or 120 g lipid per kg were each given to three replicate groups of tilapia (mean weight: 0·69 (s.e.0·02) g) reared in a closed, recirculating system. Food efficiency and protein deposition were significantly (P < 0·05) higher in fish given 50 mg vitamin E per kg diet and 75 mg/kg diet in the 50 and 120 g lipid per kg groups respectively, compared with fish given the unsupplemented control diet. Mortality of fish was not affected by dietary treatment. Weight gain and liver microsomal ascorbic acid-stimulated lipid peroxidation data analysed by broken-line regression indicated that the optimum dietary vitamin E requirements in juvenile tilapia are 42 to 44 mg vitamin E per kg and 60 to 66 mg vitamin E per kg in 50 and 120 g lipid per kg diets, respectively.
Effect of abnormal vaginal discharge at oestrus on conception rate after artificial insemination in cows
Authors: Mahmoudzadeh A. R. , Tarahomi M. , Fotoohi H.
Published: August 2016

During a 2-year study from January 1997 to December 1999, the visual characteristics of the cervical mucous discharge of cows and heifers in oestrus and their relations to conception rate were studied in a large dairy herd of Holstein-Friesian cows. Cows were divided into two groups based on mucous discharge being of normal or abnormal appearance and the group with abnormal discharge was further divided into the following classes: cervical mucus with urine (CMU), cervical mucus with microbes (CMM), cervical mucus with blood (CMB) and a group with no cervical mucus (NCM). From 6169 cases of cows in oestrus, 82·2% had normal discharge, and the remaining 17·8% had abnormal discharge classifications (6·1% CMU, 5·1% CMM, 0·5% CMB and 6·1% NCM). Conception rate after artificial insemination (AI) in the normal group (38·3%) was significantly higher than that of the abnormal group (27·9%), (P < 0·05). When the conception rate of the normal group was compared with each one of the abnormal classifications, it was significantly different from that of CMU (26·5%), CMM (22·6%) and CMB (21·8%), (P < 0·05), but not from that of NCM (34·4%), (P > 0·05). From 1734 cases of heifers in oestrus, only 6% had abnormal discharges, and the conception rates of the normal and abnormal groups were not significantly different (P > 0·05).

We conclude that AI of cows in oestrus discharging cervical mucus that is contaminated with urine, microbes or blood produces conception rates significantly lower than those of cows discharging a normal and clear mucus. Absence of a cervical mucous discharge at the time of AI of cows does not imply a low conception rate. In the case of heifers, appearance of cervical mucus had no effect on the conception rate after AI.
Multitrait and repeatability estimates of random effects on litter size in sheep
Authors: Hagger C.
Published: August 2016

Five data sets with records of first, second and third lambings of the White Alpine sheep (WAS1, WAS2), the Brown-Headed Meat sheep (BFS), the Black-Brown Mountain sheep (SBS) and the Valais Black-Nose sheep (SNS) of Switzerland were used to estimate phenotypic and genetic parameters for litter size using a multitrait and a repeatability model by the REML method. The sets contained litter information from 26 274, 25 165, 18 913, 14 953 and 21 726 ewes, respectively. Average numbers of litters per ewe were between 2·09 and 2·31. Average litter sizes at birth were between 1·36 and 1·57 lambs in first, between 1·52 and 1·75 in second and, between 1·56 and 1·86 in third parities. Multitrait estimates of heritability for size of first litters were 0·164, 0·157, 0·117, 0·223 and 0·116 for the WAS1, WAS2, BFS, SBS and SNS data, respectively. The corresponding estimates were 0·176, 0·165, 0·140, 0·208 and 0·134 for second and, 0·141, 0·155, 0·121, 0·145 and 0·107 for third litters. The systematic increase in phenotypic variances from first to third litter within data sets favoured the multivariate over the repeatability approach. Genetic correlations between size of the first three litters were, with one exception, above 0·927. Random flock ✕ year and sire of litter effects contributed between 2·2% and 13·2% and between 0·7% and 4·7% to the phenotypic variance of the traits, respectively. Residuals contributed between 70·6% and 84·2% to this parameter, estimates for the third litter were always highest. Heritability estimates from the repeatability model were smaller than the smallest multivariate estimates. Expected genetic gain in litter size from selection on the multitrait model was equal to the achieved response from the repeatability approach.
Water absorption and the drying and cooling rates in mink (Mustela vison) following simulated diving
Authors: Korhonen H. T. , Niemelä P.
Published: August 2016

The aim of the present study was to evaluate water absorbing capacity and the drying and cooling rates of fur in farmbred male mink (Mustela vison) following 10 s of simulated diving. Comparisons were made between adult animals with summer and winter fur. The water loss from a swimming pool following diving in summer amounted to 146 (s.e. 14) g and 152 (s.e. 9) g in dry and wet mink, respectively (P > 0·05). During winter the corresponding values averaged 148 (s.e. 9) and 125 (s.e. 7) g, respectively (not significant: P > 0·05). No significant differences between summer and winter were found for dry mink. In wet-coated mink, on the other hand, water loss from the swimming pool was significantly greater (P 0·05) in summer than in winter. Drying of the fur was slow and significantly (P 0·05) affected by season so that half of the 100 g water absorbed by fur evaporated within 20 min during winter (at –2°C) whereas in summer (at +18°C) it took 60 min. A slower drying rate in summer could be benefical as it allows long-term body cooling in warm environment. Cooling constants of winter-coated dry mink (0·01955 (s.e. 0·00183) per min) were not significantly different (P > 0·05) from those of winter-coated wet mink (0·02091 (s.e. 0·00144) per min) indicating that energy costs of wet fur after diving are not critical for the survivial of the mink during winter.
Effect of non-starch polysaccharides on production and absorption of indolic compounds in entire male pigs
Authors: Knarreborg A. , Beck J. , Jensen M. T. , Laue A. , Agergaard N. , Jensen B. B.
Published: August 2016

In order to study the effect of feeding non-starch polysaccharides (NSP) on the production and absorption of the malodorous compounds skatole and indole, eighteen male pigs, representing nine littermate groups, were used. One pig from each litter was assigned to either a low-NSP diet (87 g/kg of NSP) or a high-NSP diet (160 g/kg of NSP). Faecal samples and blood samples from vena jugularis were collected during a three-day period. The production of indolic compounds in different sections of the gastro-intestinal tract of six littermate groups was measured at slaughter (after 1 month on the diets). To investigate the absorption of indole and skatole, three catheterized pigs, acting as their own control (2 weeks on each diet) were used. Parallel determinations in portal blood, peripheral blood and in faeces of skatole and indole were conducted. Faecal, intestinal and blood samples were analysed for indolic compounds by high-performance liquid chromatography (HPLC). The production of indole and skatole in the proximal and distal part of the hind gut, respectively, was significantly reduced in pigs given the high-NSP diet. Similarly, both blood and faecal samples revealed that dietary NSP-inclusion reduced skatole concentration, whereas a dietary effect of NSP on the indole concentration was reflected in blood samples only. The absorption of skatole and indole was significantly lower in pigs given the high-NSP diet compared with those offered the low-NSP diet. The skatole concentrations in blood and faeces were highly correlated when measured within the individual animal, suggesting that a proportional amount of the skatole produced was absorbed. In contrast, only weak correlations were demonstrated when determined between animals. This emphasizes the great impact that individual hepatic clearance rate would have on the level of skatole in backfat, and consequently the importance of applying cross-over designs, when studying the absorption of indolic compounds.
Effects of open field testing and associated handlingv.handling alone on the adrenocortical reactivity of piglets around weaning
Authors: Herskin M. S. , Jensen K. H.
Published: August 2016

Effects of open field testing and associated handling (including blood sampling) v. handling (with blood sampling) alone on adrenocortical reactivity were investigated in piglets around weaning. After weaning at day 28, piglets were mixed to form eight replicates with three litter each and kept on slatted floors. Treatments were open field/novel object testing and associated handling (OFT + H) v. handling alone (H) (no. = 40). Testing took place on the following days (weaning day 0): -4, 0, 1, 4 and 8 (no. = 16). The open field/novel object test lasted 10 min and blood was sampled by venipuncture before and after the test and/or handling procedures. In the first blood sample, plasma concentration of cortisol did not differ between OFT + H and H piglets. In the second blood sample, however, OFT + H piglets had a higher concentration of cortisol and a larger increase in cortisol than H piglets (P < 0·01). In the first blood sample the concentration of cortisol was affected by day (P < 0·05), with concentration on day -4 being lower than those on day 0, 1, and 4 and the concentration on day 8 was lower than the concentration on day 0 as well. However, no differences were found between days for the second blood sample nor the adrenocortical reactivity. In conclusion, the increase in pre-treatment cortisol in the first 4 days after weaning as well as the lack of changes in the adrenocortical reactivity after weaning suggest that the temporal development of HPA activity and reactivity in piglets after weaning are comparable with other, more standardized long-term stressors. Exposure to an open field/novel object test and associated handling results in higher adrenocortical reactivity than handling alone but the latter (including blood sampling) in itself accounts for proportionately 0·74 of the cortisol response.
Estimating the voluntary intake and digestibility of buffel-grass and lucerne hays offered to Brahman-cross cattle using n-alkanes
Authors: Hendricksen R. E. , Reich M. M. , Roberton R. F. , Reid D. J. , Gazzola C. , Rideout J. A. , Hill R. A.
Published: August 2016

The n-alkane method was developed in temperate areas as a tool to estimate voluntary intake (VI) at pasture. The present study aimed to investigate the performance of n-alkanes as markers for estimating VI of steers (mean live weight 213 kg) offered a range of tropical grass hays and lucerne. Tropical and temperate forages have different n-alkane profiles and little is known about the issues which affect the accuracy of the method under tropical conditions. In two pen experiments (no. = 20 and no. = 24) n-alkanes were dosed using intraruminal controlled-release devices. Actual mean voluntary dry matter intakes for the diets ranged from 3·12 to 4·60 kg/day and actual mean dry-matter digestibility varied between 439 and 620 g/kg. n-Alkane profiles (C30 to C36) of the diets and the faeces for each animal were determined using gas chromatography. The recovery of each n-alkane was determined for each animal. Recoveries of n-alkanes were highly variable and generally varied between diets and between experiments. When adjacent n-alkanes were used to estimate VI (ratio method), agreement with actual VI was often poor. Despite this, where the recoveries of n-alkane pairs were similar, group mean VI were accurately estimated. From these data, it is concluded that estimation of VI in cattle offered tropical grass hays or lucerne hay, requires measured recoveries of both dosed and natural plant n-alkanes. The dosed and natural n-alkane pairs having the most similar recoveries should be used in the ratio method to estimate VI.
Ingredient apparent digestibility coefficients for the Australian short-finned eel (Anguilla australis australis, Richardson)
Authors: Engin K. , Carter C. G.
Published: August 2016

Fish meal is the most widely used protein source in commercial eel foods and information on the nutritive value of more economical protein sources is needed in order to improve cost-effectiveness of diets. This investigation was conducted to determine apparent digestibility coefficients of available plant and animal meals for juvenile Australian short-finned eel (Anguilla australis australis, Richardson). The suitability of a modified Guelph-type settlement faecal collector in eel digestibility studies was assessed. Animal by-product (spray-dried meat solubles; blood meal; high fat poultry meal) and plant protein (soya bean; canola; maize gluten; lupin; field pea) meals were mixed with a reference diet and marker (0·3: 0·69: 0·01) and the resultant test diets given to the juvenile eels (3·15 (s.e. 0·42) g) at 0·05 live weight per day. The reference diet and all the test diets were well accepted by the fish. Apparent digestibility coefficients for crude protein (ADCCP) for maize gluten meal (MGM), lupin meal (LM) and blood meal (BM) were found to be 0·97, 0·96 and 0·96 respectively and they were significantly (P < 0·001) higher than that for the other ingredients. However, apparent digestibilities for dry matter (ADCDM) and energy (ADCkJ) were significantly (P < 0·0001) higher for animal by-products than for plant proteins except for maize gluten meal. This was explained by the higher content of nitrogen free extractives in the former plant proteins. There was a strong positive correlation between ADCDM and ADCkJ for all ingredients (P < 0·01). Weaker positive correlations were also found between ADCCP and ADCDM and between ADCCP and ADCkJ. Similar results obtained for warm water species using similar faecal collection techniques and over limited eel digestibility data support the suitability of the modified Guelph-type settlement collector system in digestibility studies with juvenile eels.
Estimation of endogenous amino acid losses in growing chickens given soya-bean meal supplemented or not with DL-methionine
Authors: Fernández-Fígares I. , Nieto R. , Prieto the late C. , Aguilera J. F.
Published: August 2016

An experiment was carried out in growing chickens to study the effect of supplementation of a semi-synthetic diet containing soya-bean meal as the sole protein source with DL-methionine, to improve its biological value, on the excretion of endogenous protein and amino acids measured in lower ileum and total tract using traditional methods. Thirty-two White Rock male broilers (10 days old) were randomly divided into eight groups each of four birds, of similar body weight (mean live weight: 142·8 (s.e. 0·68) g), and individually housed in metabolism cages. Following a paired-feeding design based on metabolic body weight (kgM0·75), each group of birds was given, for an experimental period of 20 days, each of four levels of protein (60, 120, 180 or 240 g/kg; 5 days each) in two groups of isoenergetic (14·5 kJ metabolizable energy per g dry matter) and semi-synthetic diets based on soya-bean meal, either not supplemented or supplemented with 2 g/kg DL-methionine (diets S and SM, respectively). After 3 days of each treatment excreta were collected for 48 h, frozen and stored at –20ºC. At the end of the fourth treatment three chickens of each group were killed and their lower ileal contents collected. The remaining chick of each treatment was fasted for 24 h and given a protein-free diet for 8 days and excreta were collected for the last 4 days. Then (day 39 of age), chickens were killed and lower ileum contents removed and stored at –20ºC. Samples of excreta and lower ileum contents were subjected to nitrogen (N) analysis by Kjeldahl procedure and amino acid (AA) analysis by high-performance liquid chromatography. Supplementation with DL-methionine of the soya-bean meal-based diets halved total tract endogenous AA losses. Regression analysis produced a higher estimation of ileal and faecal endogenous AA excretion than feeding a protein-free diet. Endogenous AA excretion determined in the lower ileum was higher than in excreta no matter which estimation procedure was utilized. In conclusion, supplementation of dietary protein with the first limiting AA to improve its protein quality, causes an important drop in endogenous AA losses, that may have an important effect on the N economy and energy requirements in poultry. The use of regression analysis on excreta data where graded amounts of protein are given to growing chickens, seems a suitable method for determining endogenous AA losses provided that good quality proteins are used.
Energy intake and patterns of growth for male and female fallow deer of two genotypes, between 10 and 21 months of age
Authors: Mulley R.C. , Asher G.W. , Flesh J.S. , O’Neill K.T. , Ferguson J.
Published: August 2016

European (no. = 36) and hybrid (¼ Mesopotamian, ¾ European; no. = 36) fallow deer (Dama dama) were evaluated for weight gain and energy intake from 10 to 21 months of age. Twelve each of bucks, does and castrated males (haviers) were tested for each genotype, in both concentrate-fed and pasture-based feeding systems. Based on weekly weighing hybrids (H) in each of the sex classes grew more rapidly (5 g/day across all groups) than the European (E) fallow deer (P < 0·05). Haviers given concentrates grew significantly faster than pasture-fed haviers (P < 0·01), whilst does grown on pasture grew significantly faster than those given concentrates (P < 0·01). There was no significant difference in pattern of growth between bucks on pasture and those given concentrates (P > 0·05). Does grew significantly less (P < 0·01) than bucks and haviers in spring, summer and winter but environmental differences between years could not be accounted for in the analysis.

Animals of all sexes and genotypes experienced rapid growth from 10 to 12 months of age (spring) and this was associated with energy intakes according to metabolic body weight (M0·75) these ranging between 0·8 and 1·1 MJ metabolizable energy (ME) per kg M0·75 per day. There were significantly (P < 0·01) higher levels of energy consumed by H does and haviers in the summer, compared with their E counterparts but this was not associated with greater growth rates. However, H does had significantly higher (P < 0·01) dressing proportions at slaughter than E does. The energy intake on a metabolic body weight basis for most groups declined to between 0·7 and 0·8 MJ ME per kg M0·75 per day from 12 to 21 months of age, except for the does, which declined even further to between 0·5 and 0·6 MJ ME per kg M0·75 per day from 17 months of age.

There were no significant differences between E and H deer for energy intakes per M0·75, and H deer were slightly more energy efficient than their E counterparts in terms of growth rate in relation to annual gross energy intake. The food intake : weight gain ratio increased considerably for both genotypes after 14 months of age, indicating the desirability for slaughtering as soon as animals reach the target live weight. It was concluded that the crossbreeding system described is production efficient and produced offspring that reached slaughter weight sooner than E fallow deer and thereby produced carcasses with a greater wholesale value than their E counterparts of the same age.
The effects of synchronizing the rate of dietary energy and nitrogen supply to the rumen on milk production and metabolism of ewes offered grass silage based diets
Authors: Witt M. W. , Sinclair L. A. , Wilkinson R. G. , Buttery P. J.
Published: August 2016

Twenty-four multiparous ewes were used to test the hypothesis that synchronizing the hourly rate of release of energy and nitrogen in the rumen would optimize milk production. Three diets were formulated using the in situ degradability of the food ingredients, to differ in their rate of organic matter (OM) and nitrogen (N) release in the rumen. All diets contained 400 g grass silage per kg dry matter (DM) and were predicted to have a similar content of metabolizable energy (11·8 MJ/kg DM), metabolizable protein (102 g/kg DM), neutral-detergent fibre (365 g/kg DM) and daily ratio of N: OM supply to the rumen but differ in their hourly pattern of nutrient release to be either synchronous (S), asynchronous (A) or intermediate (I). The diets were offered ad libitum as a complete feed in a 3×3 Latin-square design consisting of three periods each of 28 days duration. Synchronizing the hourly supply of energy and N to the rumen did not significantly alter milk or milk fat yield (g/d), milk protein content (g/kg), DM intake (kg/day), total time spent eating or the number of meals per day. However, compared with ewes offered diets I or A, those offered diet S had a lower milk fat content (g/kg;P< 0·05) whilst protein yield (g/day) tended to be increased (P= 0·05). Animals offered the synchronous diet (S) had lower plasma urea concentrations throughout the day and significantly higher beta-hydroxybutyrate concentrations at 14:00 and 18:00 h than those offered diets I or A. In conclusion, synchronizing dietary energy and N supply to the rumen did not have a major effect on milk production in ewes.
Genetic analyses of lamb survival in Rambouillet and Finnsheep flocks by linear and threshold models
Authors: Matos C. A. P. , Thomas D. L. , Young L. D. , Gianola D.
Published: August 2016

Data on lamb survival from birth to weaning of Rambouillet and Finnsheep were analysed with sire-maternal grandsire linear (LM) and threshold (TM) models. Models for the Rambouillet included the effects of year, type of birth, age of dam and sex as fixed effects and sire, maternal grandsire and residual as random effects. For the Finnsheep, fixed effects were year-age of dam combination, type of birth-rearing and sex, and random effects were sire, maternal grandsire and residual. Restricted maximum likelihood (REML) and marginal maximum likelihood (MML) estimates of variance and covariance components were obtained under LM and TM, respectively. The performance of LM and TM was assessed in terms of goodness of fit and predictive ability. Within the Rambouillet breed, heritabilities of additive direct (0·06), additive maternal (0·04) and total effects (0·13) obtained with TM were 2, 1·3 and 1·9 times greater than those obtained with LM, respectively. For the Finnsheep data, estimated heritabilities of direct (0·17), maternal (0·26) and total (0·34) effects using TM were 1·9, 1·4 and 1·6 times greater than the estimates using LM, respectively. Estimated genetic correlation between direct and maternal effects was 0·14 for the Finnsheep with both the LM and TM. Higher genetic correlations between direct and maternal effects (0·44 and 0·62 with LM and TM, respectively) were obtained for the Rambouillet data. Goodness of fit and predictive ability of the models used with the Finnsheep data were better than for the models used with the Rambouillet data, but within breed, no sizable or significant differences were detected between LM and TM. Results indicate that maternal effects were important in lamb survival to weaning; especially in the more prolific Finnsheep breed.