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Effects of partial substitution of barley with maize and beet pulp (BP) on animal performance, rumen fermentation and rumen microbial populations were evaluated in thirty-nine newly weaned calves transitioned from a milk and pasture regime to a high-concentrate ration. Diets were: a barley-based growing diet (C); and two diets in which barley was partially replaced with maize and 10% BP (BP10) or 22% BP (BP22) on as fed basis. Wheat straw was offered ad libitum in all cases. Three adaptation protocols were followed: in Protocol 1 animals were abruptly shifted to the C diet, whereas calves in Protocols 2 and 3 were gradually adapted and received diets BP10 and BP22, respectively, for 10d; thereafter a 50:50 mixture of their diet and diet C until day 14, and finally, from day 15, diet C. All animals were slaughtered at a target live weight (LW) of ca. 500 kg. The experiment had then three phases (Ph): Ph1 (0-10d), Ph2 (11-14d) and Ph3 (15d-slaughter). Concentrate intake and proportion of straw in the diet were affected (P 0.05) among adaptation protocols. Daily rumen pH, and concentrations of lactate and volatile fatty acids were not affected by protocol. At the end of the trial, protozoa persisted in the rumen of all calves with an average concentration of 5.89 log cells/mL. Diversity dropped throughout the study; most protozoa belonged to genera Entodinium (97.5%) and Isotricha (1.7%), with minor presence of Dasytricha (0.05%), Epidinium (0.43%) and Subfamily Diplodiniinae (0.23%). Adaptation protocol had no effect on rumen bacterial population or diversity; however, both were affected by day of sampling indicating a shift in bacterial community in response to the concentrate inclusion. Although diversity dropped with concentrate inclusion, there was an increase after d10. In conclusion, the application of different protocols to adapt beef cattle to high-concentrate diets had no effect on animal performance and rumen fermentation which were not negatively affected by the abrupt transition to the high-concentrate diet. This suggests that calves might cope with those feeding conditions probably due to the microbial adaptions to a new rumen environment.

A total of 144 piglets (7.6 ± 1.7 kg) were distributed after weaning into two dietary treatments based (60%) on rice (R) or barley (B), with 18 replicates of 4 animals per treatment. On day 14 after weaning, 96 animals (48 from each diet) were reallocated in 32 pens, and assigned to a diet of the same cereal (R or B), either containing (high fibre, HF) or not (low fibre, LF) 4% of wheat bran (WB) and 2% of sugarbeet pulp (SBP), in a 2 × 2 factorial design until day 35 after weaning. No significant differences were observed on the productive performance between experimental treatments in the first period. In the second period, the piglets fed on R diet ate more (785 vs. 677 g/day, P = 0.03) and tended (P = 0.067) to have a higher final body weight (19.6 vs. 18.5 kg) compared to animals fed on diet B. Fibre supplementation did not affect performance. Both, B and HF diets reduced (P

Sixteen West African dwarf goats weighing 5.0–5.6 kg were used in an experiment that lasted 112 days to investigate the utilization of citrus pulp based diets and E. cyclocarpum . A control diet which contained 88.5% dried brewers' grains (DBG) and other three experimental diets in which DBG was replaced with dried citrus pulp (DCP) at 25, 50 and 75% levels, respectively constituted the four treatments. The goats were divided into four groups of four animals each to balance for variation in live weight before they were assigned to the four different experimental diets. Significant differences ( P P P P P IU/L ) at 75% level of citrus pulp. Therefore, the efficient utilization of citrus pulp and E. cyclocarpum by WAD goats was attained at the 50% level of inclusion in the diets.

The aim of this work was to evaluate the influence of a coarse ground cereal and two fibrous ingredients incorporated in the diet on the physicochemical properties of digesta and productive parameters of pigs during the first stage of the growing period. A total of 96 pigs (initial body weight, BW, 15 kg) were distributed into four experimental treatments: the control diet (CT) consisted of corn, barley and soybean meal milled to pass through a 2.5 mm screen; the coarse corn diet (CC) was prepared by milling the corn to a coarser particle size (4.0 mm screen); the sugar beet pulp diet (SBP) and the wheat bran diet (WB) were prepared by replacing some of the corn for sugar beet pulp (80 g/kg) or wheat bran (100 g/kg) respectively, in order to contain a higher amount of non-starch polysaccharides (NSP). Three experimental periods were considered (7, 21 and 42 days) during which body weight (BW) and voluntary feed intake were assessed. At the end of each period eight animals per diet were slaughtered. Weight of the gastrointestinal tract and its compartments (full and empty) was recorded and the contents were sampled. Digesta samples were analysed for water concentration, water retention capacity (WRC), ammonia and short-chain fatty acids concentration (SCFA). Histological study of the proximal colon tissues was also performed. In general, the different parameters evaluated showed differences between the experimental periods, but few interactions were recorded. Animals fed CC, SBP and WB diets presented a lower feed intake (P ≤ 0.009) compared to CT fed animals. Compared to the control diet, coarse grinding of corn provoked an increase in the colonic digesta content (P = 0.032). Similarly, animals fed the SBP diet compared to CT animals, showed an increase in the contents (P = 0.009) of hindgut, and in the concentration of water in the digesta (P ≤ 0.011). Compared to CT diet the SBP diet lowered the ammonia concentration in the hindgut contents (P ≤ 0.045) and increased the concentration of SCFA in the distal colon (P ≤ 0.025). Animals fed the SBP diet also showed a lower number of lymphoid nodes in the colonic mucosa compared to the other diets (P ≤ 0.043). Minor modifications were observed associated with the incorporation of wheat bran in the diet, but colonic water from WB fed animals showed a tendency to increase cytolytic capacity. The results confirm major changes in the voluntary intake and physicochemical properties of digesta as affected by the incorporation in the diet of a fibrous ingredient or coarse grinding of cereals.

Livestock genomics has gone through a paradigm shift since the advent of genome sequencing that includes Genome-Wide Association Studies (GWAS), Whole Genome Predictions (WGP) and Genomic Selection (GS). Beginning with a brief review of current progress and challenges in livestock GWAS, WGP and GS, opportunities for next generation methods are introduced that unravel the underlying systems genetics of complex traits and provide biologically meaningful and accurate predictions. Genome-Wide Epistasis Association (GWEA) and Weighted Interaction SNP Hub (WISH) network methods are introduced here to unravel complex trait genetics. These methods effectively address the problems of GWAS that have no ability to model and analyze genome-wide genetic interactions and thus do not capture any epistatic variance that could explain part of the missing heritability. Further, the Systems genomic BLUP (sgBLUP) prediction method is introduced in this paper as a next generation WGP or GS tool that can account for and differentiate SNPs with known biological roles in the phenotypic or disease outcomes and potentially increase the accuracy of prediction. It is emphasized that tools that link genetic variants to their functions, pathways and other biological roles will become even more important in the future. These tools include FunctSNP, Postgwas and NCBI2R which are briefly discussed. Genome-Wide Gene Expression (Transcriptomics) analyses using RNAseq technology are briefly discussed with some examples including results from our own pig experiments. In the last part of this review, systems genetics and systems biology approaches are introduced that involve joint modeling and analyses of multi-omics data types from genomics through transcriptomics (microarray and RNAseq), metabolomics to proteomics. It is shown using published studies that these systems approaches are valuable and powerful compared to stand-alone genomic methods in identifying key causal and highly predictive genetic variants for complex traits as well as in building up complex genetic regulatory networks. In all sections, some applications of next generation/-omics methods in livestock species (e.g. feed efficiency, growth, weight gain, fertility and disease resistance in cattle, pigs and sheep) are provided with references to relevant software and tools. In conclusion, this paper reviewed the current progress, lessons and challenges in livestock genomics and its ongoing transition to and opportunities for integrative systems genetics and systems biology in animal and veterinary sciences. Most of these integrative systems genetics and systems biology tools and methods presented here are equally applicable to plant and human genetics and systems biology.

Livestock plays an important role in the livelihoods of millions of poor smallholders within developing countries. Although it has been recognized that smallholders could benefit from genetic improvement strategies (breeding programmes), the challenges associated with establishing genetic improvement strategies for smallholder systems are considerable, resulting in limited successes to date. This paper considers the potential role of marker-based selection to genetic improvement strategies for smallholder production systems, taking into account the socio-economic, infrastructural and institutional issues. The paper stresses that no genetic improvement strategy, with or without the use of markers, is likely to succeed unless a systems approach is applied and other system constraints are met. The marker-based selection technologies discussed in this paper include marker- and gene-assisted selection, marker-assisted introgression and genomic selection. The issues addressed include the priorities of marker-based selection against other genetic improvement strategies, the potential benefits of these technologies to smallholder producers, and conditions under which marker-based selection will most likely succeed in smallholder production systems. We suggest that, of these marker-based selection technologies, marker-assisted introgression and the emerging technology of genomic selection appear to offer the most promise to smallholders, although this is yet to be clearly demonstrated. In relation to genomic selection, developing countries should maintain a ‘watching brief’ on this technology, but simultaneously act now so that they can capitalize on this technology if and when it becomes applicable in the future.

Based on individual cow live weight gain, feeding strategies were designed for individual feeding of dairy cows in loose-housing systems, and examined in a four-year production trial including 115 Danish Red (DR), 91 Danish Holstein (DH), and 93 Danish Jersey (DJ). The objective of the present paper was to examine the milk yield obtained in response to three feeding strategies. The interrelationship between feed intake and live weight changes is presented in a companion paper. Cows were stalled in a loose-housing system based on automatic milking, automatic recording of feed intake and automatic weighing of the cows. All cows had 3 kg of individually separately offered concentrate (ISC) in addition to a mixed ration (MR). Cows were either allowed a medium energy MR during whole lactation (strategy MR1) or a high energy MR during early lactation, which was reduced to a low energy MR either early or late (strategy MR2-E and MR2-L). The early and late changes were defined as a live weight gain after live weight minimum at 15 and 35 kg, respectively, for DR/DH and 11 and 25 kg, respectively, for DJ. When MR energy concentration was changed, cows on the MR2 strategies were offered 3 kg per day of extra concentrate. The total allowance of 6 kg ISC was stepwise reduced to 3 kg per day as live weight continued to increase until 50 and 35 kg for DR/DH and DJ, respectively. Compared to feeding the MR1 strategy, the analysis showed that feeding the MR2 strategies did not significantly affect milk yield within primiparous DR and DH or within any DJ, as total lactation feed energy intake within these groups of cows was not significantly affected by the feeding strategy. Results obtained for multiparous DH showed that it is possible to increase milk yield without reducing the milk:feed ratio, when MR2 strategies were applied compared to the MR1 strategy. Feeding high energy rations during early lactation caused a higher peak feed energy intake within multiparous cows of DH and DR, but only multiparous DH obtained higher peak ECM yield in response to higher feed energy intake in early lactation. Across breed the results suggested that cows offered the MR2-E strategy might obtain higher lactation ECM yield compared to cows offered the MR2-L strategy due to a higher ECM yield persistency obtained by cows offered the MR2-E strategy. Results on feed intake and live weight changes presented in a companion paper indicated, that cows offered the MR2 strategies obtained a lower extent of mobilization compared to cows offered the MR1 strategy, and feeding the MR2-E strategy significantly increased duration of the mobilization period, which might have increased MR2-E cows' ability to maintain a high milk production during mid lactation.

The objective of this paper is to review the existing literature regarding the advantages and disadvantages that different weaning practices have on the stress responses and productivity of water buffalo in different breeding systems. On farms where water buffalo are bred for milk production, early weaning favors the amount of milk produced, reduces breeding costs and improves the reproductive rate. However, this early separation may be associated with the restriction of colostrum and essential nutrients for water buffalo calves, which cannot be replaced by the use of milk replacers made for cattle. Consequently, colostrum restriction can lead to an increase in disease susceptibility, high mortality rates and compromises future performance. In addition, mothers show a more temperamental behavior, making milk ejection difficult due to the anatomical characteristics of the udder in this species. On the other hand, a continuous suckling system may be more beneficial to weight, immune status, and welfare of calves but may cause economic losses due to delayed postpartum estrus. The results in terms of susceptibility to stress are contradictory; some authors conclude that separation between mother and calves does not generate stress, as long as weaning is carried out within the first hours or days after birth (3–6 days old) after colostrum intake, compared to weaning at 45 and 90 days. However, these calves have greater difficulty in learning to eat on their own and show an increase in abnormal behaviors. The most commonly utilized form of weaning is abrupt. Behavioral and physiological indicators suggest that abrupt weaning is stressful for both the mother and the offspring. The protocols for performing gradual weaning seem to offer advantages in reducing stress in buffalo compared to abrupt weaning. On buffalo farms, calf management is one of the critical points of breeding, therefore, more studies are required to improve current breeding systems and promote the welfare of water buffalo calves.

This paper forms a part of a series of studies aiming to estimate the costs of abortion in Iranian dairy herds. In previous studies we have determined mastitis as a significant risk factor for abortion. In order to provide a more reliable estimation of the costs associated with abortion in Iranian dairy herds, the risk of a cow getting infected with mastitis needs to be included. Data from 6 commercial herds and 32,191 cows was assigned to 3-weeks in milk (3-WIM) records from 1 to 567 d after calving (1st–27th 3-WIM). The effect of herd, parity, calving season, past incidence of abortion, cumulative FCM yield level (CFCML), past incidence of mastitis in previous 3-WIM periods (EMAS), days in milk (DIM) and their significant 2-way interactions on mastitis in current 3-WIM period (MAS) were evaluated using a logistic regression model. Mastitis rate (MR) in studied herds was on average 28.3%. Results show that herd, parity, EMAS, CFCML, calving season, and lactation stage significantly (P It can be concluded that a risk factor analysis with all significant interactions is more informative than a model without the interactions, especially when making the optimal decision for a cow with given characteristics. Moreover, knowledge on the effect of influential factors on mastitis will be useful when designing mastitis control programs at herd or national level.

Woody rangelands are important forage resources for grazing goats in the Mediterranean basin. Goats are well adapted in these heterogeneous and complex ecosystems due to their particular anatomic characteristics, metabolic efficiency and browsing ability. However, the mechanism of grazing behavior and forage selection in goats is quite complex and depends on several factors. The present study deals with the seasonal changes of chemical composition in the selected forages and ingested diets as well as their effects on milk yield and composition of goats grazing in a Mediterranean woody rangeland. Hand plucked forage samples similar to those consumed by the goats were collected for chemical analysis. The nutritive value of consumed forages, in combination with the different feeding and grazing system per trial period, influenced milk quality and performance. The replacement of feed supplementation with an increase of the contribution of grazing in the rangeland could maintain the milk yield and quality at the late stage of lactation. In addition, this paper focuses on the influence of the chemical composition of selected forages on the diet selection of goats using a modeling approach. The model showed a high interpretative accuracy and explanatory value (R2 = 0.923) and was able to distinguish the goats' most important criteria for selecting among the forage plant species in relation to several factors. The results indicate that the dietary preferences of goats were influenced, not only by the seasonality of nutritive value and availability of forages in the rangeland, but also by the plant origin of each nutrient source. The selection of Quercus frainetto was highly correlated with its NDF content. Herbaceous species, Cistus creticus and other woody species were mainly selected due to their CP content. The ADL content seemed to have the lowest influence of all nutritive variables on the selection among groups of plant species. The modeling approach, apart from the understanding of grazing behavior of goats, offers additional information that can be useful to the shepherds in order to manage more effectively the feeding and grazing system of their goat's flock.

The spleen plays a key role in immune regulation. Progesterone (P4) exhibits different immunological effects through binding to different types of receptor. In the present study, splenic samples were obtained at day 16 of non-pregnancy and days 13, 16, and 25 of pregnancy to study the expression of P4 receptor (PGR) and P4-induced blocking factor (PIBF) in ewes through quantitative real-time PCR, Western blot and immunohistochemistry analysis. Our results showed that the relative expression levels of PGR and PIBF mRNA increased from day 13–16 in pregnant ewes, but decreased from day 16–25, and the 26 kDa isoform of PGR and the 22 kDa variant of PIBF were down-regulated in the spleens at day 25 of pregnancy compared with expression at day 16 of the oestrous cycle and days 13 and 16 of pregnancy. The immunohistochemistry test results confirmed that PGR and PIBF proteins were localized in the cytoplasm of cells in the capsule, trabeculae and splenic cords. This paper reports for the first time that the 26 kDa isoform of PGR and the 22 kDa variant of PIBF were down-regulated during early pregnancy, which may be essential for normal pregnancy in ewes.

The effect of vitamin E supplementation on the growth performance, carcass traits, meat quality, and immune response of male broiler chickens was studied using a meta-analysis. The database was consisted of 51 scientific papers published in peer-reviewed journals. The dependent variables for meta-analysis included final body weight, average daily gain, daily feed intake, feed conversion ratio, vitamin E concentration in the muscle, tissue polyunsaturated fatty acid concentration, lipid peroxidation value, post mortem pH, heterophil to lymphocyte ratio, and total immunoglobulins. Linear mixed models were used to analyze the data. Vitamin E supplementation did not influence growth performance, as the estimated slopes were not different from zero, with P-values equal to 0.92 for final body weight, 0.81 for average daily gain, 0.31 for daily feed intake, and 0.83 for feed conversion ratio. Dietary vitamin E supplementation increased the vitamin E content in the muscle (P = 0.001), did not change the polyunsaturated fatty acid concentration, and decreased the lipid peroxidation (P = 0.01). The immune response was improved, the heterophil to lymphocyte ratio was constant, and the total immunoglobulins were increased (P = 0.037) by dietary vitamin E supplementation. With regard to broiler chicken performance, there seemed to be no relationship between dietary vitamin E supplementation and growth performance. There is ample indication that meat quality and immune response could be improved by dietary vitamin E supplementation.

Horse conformation has been proposed as an indirect indicator of performance, since their genetic correlations are often positive and high. In Pura Raza Espanol (PRE) horses, the selection of conformation traits more related to functionality and performance allows a pre-selection of animals and contributes towards saving costs and increasing the genetic progress. The aim of this paper is to evaluate the predictability of 16 conformation traits (14 body measurements and 2 linear conformation traits) in adult PRE horses, focusing on the conformation traits of foals. The dataset included 155,716 records (82,408 young and 73,308 adult horses) with conformation traits from 142,244 different horses, aged between 1-36 years old. Animals between 1-3 years old were included in the ‘young’ group and older animals in the ‘adult’ group. A univariate General Linear Model procedure followed by a Tukey-post-hoc test were used to assess the statistical significance of non-genetic effects. Heritability values were estimated univariately. The fitted models included breeder, age and inbreeding (F) as covariates, and sex and coat colour as fixed effects. Coat colour and F were significant for 75% and 87.5% of the traits analysed, respectively; and the other effects analysed were significant for all the conformation traits. Heritability values ranged between 0.178±0.0063 and 0.795±0.0098 in young horses, and between 0.273±0.0038 and 0.894±0.0007 in adult horses. The genetic correlations of the conformation traits between young and adult horses were above 0.75 for 93.75% of the conformation traits analysed, which confirms the efficiency of pre-selection in young horses based on conformation features to predict their adult performance.

Intensive genetic selection has improved productive traits in poultry and contributed to changes in systemic metabolism; however, their blood coagulation processes have received little study. The precise physiological mechanisms of haemostasis in birds remain poorly understood, but blood clotting is believed to be governed by an extrinsic tissue factor-dependent pathway, with some residual intrinsic pathway serving an ancillary function. Disorders of haemostasis are a common pathology in poultry rearing, manifested by bleeding, which most often occurs in the muscles, intramuscular fat, connective tissue and internal organs. Efficient diagnosis of haemostatic disorders in poultry remains an ongoing problem. The diagnostic methods currently in use in veterinary medicine are inadequate for evaluating haemostatic disorders. The optimisation of coagulometric methods and the availability of species-specific reagents remain significant obstacles. Furthermore, although vitamin K is essential for the synthesis of extrinsic coagulation factors and interacts with vitamin D in bone formation, it is frequently deficient in birds. The objective of the paper is to present the current state of knowledge of haemostatic disorders in poultry, and to stress the need to develop more detailed laboratory procedures and methods of producing species-specific reagents for determination of haemostatic parameters to deepen the understanding of blood clotting in birds.

This paper investigates the factors affecting the implementation of various management activities related to the characterization, use and conservation of animal genetic resources (AnGR) across countries. The 128 official country reports provided for The Second Report on the State of the World's Animal Genetic Resources for Food and Agriculture were analysed based on a multivariate approach. These reports investigated topics related the national level of AnGR diversity, the extent of characterization activities, use and breeding programmes and conservation activities, as well as capacities in AnGR management and the use of biotechnologies related to livestock breeding. A large part of the variability (34.7%) of the dataset could be explained by one synthetic variable, which could be interpreted as the general extent of AnGR related activities, and indicate that country efforts on AnGR are directed relatively homogenously towards the various activities and species considered. This variable differentiated mainly OECD and BRICS countries from less developed ones. OECD and BRICS countries also appeared to be differentiated with respect to the use of some specific biotechnologies such as cloning, genetic modification and transplantation of gonadal tissues. With regards to economic and development indicators, the first synthetic variable showed large correlation with the number of researchers in agricultural sciences per inhabitant ( r =0.643) and national GDP (r=0.516). Capacities in research therefore appeared to be one of the main enabling forces for activities related to AnGR and the implementation of the Global Plan of Action (GPA) for AnGR.

Horse conformation is considered an indicator of performance, which plays an important role in breeding decisions. Apart from conformation, Pura Raza Espanola horse (PRE) breeding goal is to improve its functionality, and they are being selected by some studs over the last decades as a dressage sport horse. This process may be accompanied by a mass selection which has probably caused morphological changes in recent decades. This paper has three main aims: To evaluate the development of body conformation in PRE over the last three generation intervals (GI), to evaluate the current morphological differences of PRE selected for dressage competitions by specialized stud farms with others with the others and to estimate the genetic parameters in order to show the response to individual mass selection. A maximum of 26 morphological measurements (MM) from 52,681 PRE collected between 1980 and 2013 were split into three groups of 11 years (GI). The GLM showed that gender and GI were significant factors in all the MM analyzed in the last 30 years. In the current PRE population, gender and belonging to a stud attached to the official dressage improvement program were significant factors for 17 and 16 MM respectively. The heritabilities ranged from 0.31 (angle of shoulder) to 0.80 (height at withers). There 57.5% of the genetic correlations were higher than 0.50. The predicted breeding values were different for dressage and non-dressage subpopulations.

The aim of this review paper is to present and discuss the current experimental findings describing the effects of dietary oils on the functions of immune cells and the efficacy of different mechanisms of the immune system in poultry and pigs. The majority of experiments of this kind have focussed on dietary sources of n-3 polyunsaturated long-chain fatty acids (n-3 PUFAs). Their results have shown a significant association between dietary fat (i.e., the level of n-3 PUFAs as well as n-6:n-3 PUFAs ratio in the diet) and different mechanisms of immune response. Dietary supplementation with rich sources of n-3 PUFAs, especially with fish oil, can have a beneficial, modulating influence on the immune system; specifically they appear to decrease acute and chronic inflammatory immune reactions and simultaneously to improve indices of specific immune response. However, several studies demonstrated that anti-inflammatory properties of n-3 PUFAs do not always result in improvement of growth or egg performance.

Naturally hornless cattle are called polled. The possibility to introgress the allele responsible (P) for polledness in a cattle population that is more intensively selected for other traits is investigated in this paper. Gene introgression, generally carried out by several steps of backcrossing and selection, takes a long time and may lead to unacceptable genetic loss in other traits or inbreeding. The main objective of the current study was to evaluate the use of genomic selection to speed up the introgression of a target allele in a conventional dairy cattle breeding scheme with overlapping generations. A cattle population and a breeding program were simulated and run over a 12 year selection period. Assuming that the polled population was inferior for overall genetic merit , two selection strategies were evaluated: i) selection on conventional BLUP-EBV (CBLUP); ii) selection on genomic EBV (GEBV) obtained with the genomic relationship matrix used in BLUP (GBLUP). Both selection strategies were applied with (PSEL) and without (NOPSEL) selection for the single polled locus (P). The overall level of genetic merit, the P allele frequency and the inbreeding level (F) in the new born animals were monitored each year, as well as the average genetic gain per year of selection (ΔG). The overall genetic level of new born animals was higher for GBLUP compared to CBLUP, with an average ΔG/year of 8.34% (GBLUP) against 7.49% (CBLUP). The PSEL scenario reduced genetic gain, but P allele frequency increased from 0.130 to 0.415 (CBLUP) and from 0.128 to 0.440 (GBLUP) for PSEL, after 12 years of selection. No substantial changes in allele frequency were recorded for NOPSEL scenarios, both for CBLUP and GBLUP breeding schemes. The overall inbreeding rates for GBLUP were 0.28%/y (NOPSEL) and 0.30%/y (PSEL) and for CBLUP 0.52%/y (NOPSEL) and 0.44%/y (PSEL). In conclusion, application of GS to gene introgression helped to speed up the process of introgression of a gene while simultaneously increasing the genetic gain and reducing the inbreeding rate.

The present paper was designed to assess the effect of Mycobacterium avium subsp. paratuberculosis (MAP) infection status (antibody positive vs antibody negative, as measured by ELISA) on time to culling and calving difficulty in dairy cows. The study was carried out in 8 dairy farms in Galicia (north-west Spain). All of them were taking part in an ongoing paratuberculosis control program, as well as in a dairy herd improvement program. In order to estimate the relation between time to culling and MAP serological status of dairy cows, the present study followed the Andersen–Gill model for survival analysis. Similarly, in order to evaluate the influence on calving difficulty an ordinal logistic regression model was applied. The results indicated that seropositive cows were more likely to be culled due to death/urgent slaughter (hazard ratio=1.88), low productivity (hazard ratio=2.55), infertility (hazard ratio=4.64) and other causes (hazard ratio=1.67). Additionally, the probability of difficulties at calving time was 2.74 times higher for seropositive cows. The estimated effects could determine the economic benefits of a paratuberculosis control program.

International audience; In the 1980s, Olkuska sheep went through a dramatic decline in population size, which resulted in a rapid increase in the inbreeding level. Implementation of conservation program led to enhancement of the number of flocks and resulted in establishment of flocks in regions far away from the center of origin of the breed. In this study, we analyzed genetic variation within this unique breed to better understand genetic structure and to support enhanced management strategies. The analysis of genetic diversity in Olkuska sheep was performed using two sources of information, pedigree and genomic data. Single nucleotide polymorphisms (SNP) data supported analysis of runs of homozygosity (ROH), inbreeding coefficient F-ROH, genomic inbreeding F-HOM, linkage disequilibrium and observed heterozygosity. On the basis of the pedigree data, inbreeding coefficient (F) and coancestry were calculated. Both sources of information provided similar results in regard to inbreeding level and showed significant differences between the Southern and the Central subpopulations of the breed. The average inbreeding coefficient (F) was 0.102 in the Southern subpopulation and 0.053 in the Central subpopulation. The average F-ROH in the Southern population was 0.124, and 0.082 in the Central population. The highest number of ROHs were observed on OAR1, OAR2 and OAR3. Most of ROHs were short (1-10 Mb). The pattern of ROHs detected in the study on Olkuska sheep is similar to other research findings cited in the paper. Significant differences between two subpopulations within the local breed which in the past went through a major decline in numbers, creates the threat of genetic diversity loss. Exchange of individuals between flocks located in the south and in the central Poland is strongly recommended.

This paper suggests methods to monitor sows׳ activity before, during and after farrowing using sensor data. The progress of parturition is analysed from video recordings for a total of 19 sows, of which half was provided with straw (S), and half received no straw (NS). The pre-partum high active behaviour is defined as the hours when the sows performed more than 50% active behaviour per hour, allowing for 1 h of resting. It is characterised by its duration, intensity and its last hour as compared to the onset of parturition. No difference is observed for the duration and last hour of pre-partum high activity for Group S and Group NS. Nevertheless, the intensity indicates that Group S tends ( p =0.07) to be more active (80%) than Group NS (70%) during the pre-partum high activity. The last hour of the pre-partum high active behaviour and the increase of the Lying Active behaviour characterise the onset of farrowing; and a reduction of the number of activity shifts characterises the end of farrowing. No difference of activity is observed for sows farrowing at night vs. in the daytime. Finally, results indicate that sows with a long pre-partum high activity also have more of long birth intervals (more than three times the median) during farrowing. In conclusion, the methods appear promising to monitor the activity around farrowing, and is less time consuming than video analyses. A better monitoring of these phases can potentially result in a better welfare and a reduction of piglet mortality.

Genomic prediction of genotyped individuals utilizes estimates of the effects of alleles at many loci to predict performance. Estimates of allele substitution effects are commonly obtained from multiple regression linear models. In those models, allele substitution effects tend to be treated as random effects, which shrinks their estimates compared to treating them as fixed effects. A number of alternative models that vary subtly can be used in these endeavors. Bayesian approaches that utilize Markov chain Monte Carlo methods that repeatedly sample allele substitution effects are widely used to fit these models. Genomic prediction of non-genotyped individuals utilizes predicted marker genotypes of non-genotyped individuals as well as covariance information based on pedigree relationships. Genomic prediction methodologies continue to evolve, representing a synthesis of approaches, and this paper documents that evolution.

[EN] The inclusion of genomic information on prediction of breeding values has been explored by the pig breeding industry as molecular techniques evolved. Except for a few successful cases, for example the HAL-1843 (R), the use of genomic information for pig breeding has been limited. The development of SNP chips with high density markers across the genome coupled with new statistical methods allowed genomic selection (GS) to become a common practice. GS application entailed important advantages for pig breeding as it increased the accuracy of the breeding values for selection candidates and offered an opportunity for the practice of new selection strategies. Nevertheless, the application of GS is not straightforward for every target trait and breeding scheme. Many efforts have been done to evaluate the new methods and strategies to efficiently implement GS in pig breeding. Several aspects of the population and breeding objectives must be considered before GS is applied. This paper reviews the current status and challenges faced by pig breeders in the implementation of GS and the future opportunities that may arise as molecular technologies advance. (C) 2014 Elsevier B.V. All rights reserved., This work was partially funded by the Ministerio de Economía y Competitividad, Spain (Project RTA2012-00054-C02-01).

Wolf, B. T., McLean, B. M. L., Davies, O. D., Griffith, J. B. (2014). Performance of purebred Welsh Mountain and cross bred ewes in a hill environment. Livestock Science, 165, 181-188 Paper submitted 9-8-13

Seasonal low-input milk production receives increasing interest in Alpine regions. In contrast to typical pasture-based, seasonal milk production regions such as Ireland or New Zealand, the harsher climatic conditions in the Alps require a 5–6 months barn feeding period. In addition, the dairy cow types commonly used in Alpine regions have not been selected under low-input conditions. Among others, this raises the question of the optimum calving season for different Alpine dairy cow types in low-input systems. The aim of this paper was therefore to investigate the effect of calving season on diet composition and productivity of two different cow types in an Alpine low-input and pasture-based production system. Thirty four lactations of Brown Swiss (BS) and 39 lactations of a special strain of Holstein Friesian (HFL) were compared in a seasonal, low-input system. The BS cows represented the average Austrian BS population and were primarily selected for high milk yield. HFL is a local strain of Holstein Friesian and was primarily bred for lifetime performance under low-input conditions. The dataset comprised cows which calved during the barn feeding period (late October/early November until late March/early April); the grazing period lasted from April until October. The date of calving was expressed relatively to the date of turn out to pasture and was included as a continuous covariable in a mixed model. As expected, moving calving dates towards spring increased the proportion of pasture in the diet and decreased concentrate consumption for both breeds. A significant interaction between breed and calving date was found for milk and milk solid yield per lactation, which decreased for BS when comparing autumn and spring calving, while it remained relatively stable for HFL. However, the larger quantities of concentrates fed to cows calving in autumn, did not reduce body weight loss of BS. The results indicate that for HFL spring calving is likely to be more suitable in order to yield the full economic benefit, while moving calving dates towards autumn might support BS to exploit its greater genetic merit for milk production.

In breeds where a large fraction of animals with records on a maternally affected trait are from dams that have no records and unknown parents, the genetic evaluation of such trait may be hindered by misspecification of the genetic covariance matrix. The specified covariance structure for the additive direct and maternal effects in the regular maternal animal model (MAM) when dams have no records differs from the covariance between relatives with maternal effects. Two solutions are possible. One is to include in the vectors of breeding values for direct and maternal effects the dam or a “phantom” dam if the latter is unknown. As a consequence, the number of equations to be solved in the MAM may increase considerably. Alternatively, one may replace the maternal breeding value of the dam with 2/3 of the maternal breeding of the individual, and −1/3 of the maternal breeding value of the sire of the individual. As this “regression” of breeding values has been largely ignored, the goal of this paper is to present a parsimonious equivalent MAM using such regression. The approach is extended to a similar situation for models with grand maternal effects. Two small numerical examples are used to illustrate the proposed methods.

This paper revises the evolutionary history of the stem root of the genus Equus from Eocene period (54 million years before present, MYBP) to present. It also assesses molecular taxonomy and evolutionary relationships of this line since the first appearance of fossil records in terrestrial deposits. Combining these two lines of evidences, we outline a more informative and consensus phylogeny in a more understandable context. We also compare and contrast evolutionary histories and phylogenetic relationships of equids inferred from paleontological as well as varieties of molecular data and their implications. Using pair-wise coalescence time estimates, we draw a consensus speciation order in the stem root of the genus Equus. With the help of molecular data, we suggest the reasons for enigmatic speciation events between asses and zebras as well as the backgrounds for genetic dissimilarities between hemiones of Asia and asses of Africa regardless their phenotypic similarities. Based on the evidences from molecular data and review of late Pleistocene megafauna extinction in the Americas, we believe that horses were certainly domesticated in the Eurasian Steppe or elsewhere that survived late Pleistocene megafauna's extinction than in the Americas. We discuss the true wild horse that was involved in horse domestication processes in line with recent evidences that unraveled multi-geographic origins and multi-maternal lineages in the present day domestic horses.

The aim of this paper is to review the existing literature concerning environmental enrichment for suckling piglets and lactating sows and the effects on behaviour and mortality. Most research considering environmental enrichment still focuses on weaner, grower and finisher pigs. However the European Union Directive 2001/93/EC states that all pigs should have access to a sufficient quantity of material to enable proper investigation and manipulation activities. Fortunately, research on environmental enrichment and alternative housing for piglets and sows is growing and results show important beneficial effects on welfare of both piglets and sows, by providing opportunities to engage in explorative behaviour, nest-building and social interactions and improving maternal responses. Social enrichment, increased space allowance and/or straw provide promising results on welfare but are not always practical to implicate and bring forth other potential risks and concerns. Therefore, it would also be interesting to further examine the potential of other types of enrichment, such as objects or sensory enrichment (e.g. pheromones), as possible applications and their effects on piglet and sow welfare. Other aspects which need more clarification are the relation between environmental enrichment during the farrowing period and weaning age and the relation between painful procedures, such as castration and tail docking, and environmental enrichment on the behaviour of piglets.

This paper explores the potential of using locally produced protein sources in diets for growing lambs in northern Europe. The aim of the research was to evaluate the effects on lamb growth performance of peas, rapeseed cake and hempseed cake as protein supplements in barley-based diets. Forty-eight crossbred (White Swedish Landrace × Texel) ewe lambs were penned, forming experimental units allotted to one of four experimental diets. The lambs were on average 87 (SD = 9) days of age at the start of the eight-week continuous trial, during which their live weight (LW) was recorded weekly. The four experimental diets were barley-based, with 101 g hay/kg diet on a dry matter (DM) basis. The control diet (B-0), without protein supplement, contained 112 g crude protein (CP) and the calculated metabolisable energy (ME) value was 13.0 MJ/kg DM. The other diets contained peas (B-P), rapeseed cake (B-RC) or hempseed cake (B-HC) and had similar CP concentrations (160–162 g/kg DM), but varied in ME content (13.4, 13.4 and 12.2 MJ/kg DM, respectively). Rumen undegradable CP (RUP) was 231, 99, 298 and 291 g/kg CP, with an intestinal digestibility of 605, 707, 528 and 307 g/kg RUP for the concentrates of barley, peas, rapeseed cake and hempseed cake, respectively. There were no significant differences in DM intake, which varied between 860 and 989 g/d, for the lambs on the different diets. However, CP intake was higher for lambs fed B-P and B-HC ( P P = 0.037) than for the other diets, among which there were no significant differences in these respects. Initial LW of the lambs did not differ significantly between treatments, but final LW was higher for lambs fed B-P and B-RC ( P = 0.029). Total gain and average daily gain were highest for the B-P treatment, followed by the B-RC treatment ( P P

Somatostatin (SS) and growth hormone-releasing hormone (GHRH) are synthesized and secreted by the hypothalamus, which mediates the synthesis and secretion of the growth hormone (GH) from the hypophysis, as well as regulates the GH concentrations in animals and humans. In this paper, we describe the regulation of animal growth using plasmid DNA-encoding GHRH gene. In this study, we introduce a gene transfer technique mediated by PLGA microspheres. The eukaryon expression vectors based on the RNA replicon, namely, pCMV-Rep-GHRH, were constructed; further, poly( d , l -lactide-co-glycolide) (PLGA) microsphere-encapsulating plasmids were prepared. Gilts were intramuscularly injected at day 85 of gestation with 1 or 5 mg of pCMV-Rep-GHRH microspheres. Piglets were weighed following birth and at days 20 and 50 postbirth. Blood samples were collected at day 50 to evaluate serum IGF-1 and GHRH concentrations. The result showed that the birth weight of the piglets at 20 d and 50 d were significantly higher (by 20.32–110.76%; P 0.01) than that in the group injected with saline-MP. After 50 days, the concentrations of serum IGF-I in the treatment groups injected with plasmid were observed to be significantly higher (2.5 times; P 0.01) than that in the group injected with saline-MP; the concentration of serum GHRH was higher than 21% in 1 case ( P 0.01). The lymphocyte stimulation indices detected confirmed that GHRH gene transfer could improve immunity in first-generation progeny pigs. The results of this study confirmed that PLGA microsphere-mediated GHRH expression in pregnant pig skeletal muscle enhanced the body weight of piglets prior to and following birth.

This paper aimed at evaluating closed and open nucleus schemes for Boran cattle based on genetic and economic merits of three alternative breeding programmes; 1) breeding programme closed to the members of the Boran Cattle Breeders Society aimed at improving growth (ENTIRE), 2) expanded breeding programme managed by the ENTIRE but incorporating the trait preferences of low-input farmers aimed at improving growth and adaptation (EXPO) and 3) breeding programme for the low-input farmers aimed at improving adaptation, growth and milk production (LOW). Within ENTIRE, two options were considered; option 1 included breeding objectives and selection criteria derived from the recommendation for ENTIRE (ENTIRE1) and option 2 included breeding objectives and selection criteria derived from the recommendation for the EXPO breeding programme but without extra recording for packed cell volume (ENTIRE2). Sensitivity analysis of the programmes to changes in nucleus size (5%, 10% and 25%), gene contribution to commercial herds (25%, 50% and 70%) and degree of opening the nucleus (10%, 20% and 30%) were performed. The ENTIRE1 within closed nucleus programme obtained overall monetary genetic gain of US$1.16 1 and profit amounting to US$5.36 and for ENTIRE2, the monetary genetic gain and profit rose to US$2.01 and US$11.10, respectively. The open nucleus posted higher values than the closed nucleus for monetary genetic gain (US$1.46) for ENTIRE1 but had a lower profit (US$5.02). This was a general trend in the alternative programmes. Moving from ENTIRE (growth) to EXPO (growth and adaptation) resulted in the drop in sale weight gain by almost 2 kg, but a gain of 20% in packed cell volume. The LOW posted a negative gain for milk yield of − 1.1 kg. Restrictions on growth and adaptation on the breeding objective allowed for moderate positive gains in milk. The nucleus size of 25%, genetic contribution to commercial herds of 70% and degree of opening the nucleus of 10% were most profitable. When extra recording for packed cell volume was applied in the commercial herds in EXPO, no additional benefits accrued. The trade-offs for ENTIRE due to incorporation of adaptation traits as well as the feasibility of the alternative breeding programmes are critically discussed.

Breeding objectives for meat sheep in Ireland have been defined and used in the development of selection sub-indices to provide commercial producers with an economic comparison of animals for specific performance trait groups. Using trait-by-trait bio-economic models and a range of methodologies, economic weights (in € per lamb born per genetic standard deviation in the trait) have been calculated for maternal and terminal sire performance traits as follows: production traits; −€1.41 for days to slaughter, €0.35 for carcase conformation class, −€0.52 for carcase fat class, lambing traits; −€0.69 for lambing difficulty for single-bearing ewes, −€0.37 for lambing difficulty for multiple-bearing ewes, €1.15 for lamb survival, maternal traits; €0.83 for number of lambs born, −€1.49 for ewe mature weight, health traits; −€0.09 for lamb foot rot, and −€0.82 for ewe foot rot. Results indicate the significant value of improving the ability of lambs to survive to weaning, without increasing number of lambs born. The highly negative economic weight for both days to slaughter and mature size represents a powerful unfavourable relationship between the two traits. Economic values for lambing difficulty and foot rot represent the significant costs these traits have in the Irish sheep production system. In the early stages of the development of the genetic improvement program for sheep in Ireland the breeding objective defined in this paper provides directed emphasis for trait recording, selection strategies, and mating systems. In addition the economic weights provide indications as to how much genetic improvement in a specific trait would be worth paying for. The proposed formulation of the total economic index as sub-indices provides the ability for commercial farmers to adjust breeding emphasis towards specific market outcomes or address key production aspects in their particular farming system.

This paper reports on calving data from a cow family in New Zealand which is elite for triplet calving ability. The foundation cow (named ‘Treble’) was born in 1993 and her calvings included three sets of triplets. A triplet son (named ‘Trio’), born in 1996, was used for matings in two New Zealand herds, producing 44 daughters which were retained for breeding, and these had a total of 109 calvings by 2008. Thirteen of the daughters produced a total of 15 twin and 6 triplet sets, 19% multiples (including twins and triplets). Five cows calved the 6 triplet sets; triplet calvings were 29% of all multiple calvings. This herd should provide a resource for DNA studies to identify a genetic mechanism whereby rare triplet calvings are produced.

Trotting racing is one of the most popular horse sports in Europe. The Spanish Trotter Horse (STH) can be considered as a composite of the main World trotter populations. This is because the Spanish Trotter Breed often imports breeding stock from the main Trotter Horse Breeds; mainly American and French Trotters. The Breeding Program of the STH includes earnings, placing and time traits as main selection criteria. The main aim of this paper is to estimate the genetic parameters in the STH population and to show the characteristics of the STH population as a connecting population in order to include it in an international breeding evaluation for trotting ability. For this purpose, we used 285,538 racing records from 5086 horses during a 16 year period. All the known ancestors of the recorded animals were included in the pedigree file (10,940 horses), making sure that at least four generations for foreign horses were included. A multivariate Animal Model was developed using four different performance traits: annual earnings (log transformed), percentage of first placing in a year (square root transformed), time per kilometer and best racing time per hippodrome and type of start . Genetic connectedness of performance data was adequate. The estimates of heritability ranged between 0.14 ± 0.017 for the percentage of first placing and 0.29 ± 0.018 for the best racing time per hippodrome and type of start . The other traits had a medium magnitude of heritability, and were 0.27 ± 0.018 for the annual earnings and 0.28 ± 0.017 for the annual earnings and the time per kilometer . All these values were within the range with those reported by authors for other trotter populations. The repeatability values had ranged between 0.31 for the percentage of first placing and 0.65 for the time per kilometer . The genetic correlations have medium-high magnitude, ranging between 0.61 ± 0.044 and 0.99 ± 0.005. There was a negative correlation between time traits and the other analyzed traits, as was expected because a decrease in the time traits is always related to an improvement in the performance results in races. Given its own genetic composition, the population of trotter horses in Spain could be considered as a connecting population in order to develop an international genetic evaluation. Therefore, these parameters could be taken into account for an international genetic evaluation of trotter horses.

There is growing interest in the environmental benefits of grazing by cattle, yet little information is available regarding the levels of production that might be achieved on semi-natural rough grazing (SNRG). The overall aim of this research was to assess the performance of native and ‘improved’ breeds of cattle when grazing grass/clover swards and SNRG in order to explore potential genotype × nutritional environment interactions. This paper reports the findings of three experiments conducted over three years. The first experiment assessed the performance of autumn-born Welsh Black (WB) and Charolais cross (CX) cattle aged approximately 9 months when grazing ryegrass/white clover-dominated improved permanent pasture (PP) and Molinia caerulea-dominated SNRG. Both genotype and pasture type had significant effects on liveweight gain, with growth rates higher for WB steers than CX steers (P

Acornweight, size, shape and composition varya great deal among evergreen oaks (Quercus ilex rotundifolia); however these characteristics remain constant for a tree throughout the fruiting period. The number of consumed acorns under the canopy of a tree could be an indicator of preference for its acorn characteristics. This paper analyses the characteristics of the acorns selected by free-ranging Iberian pigs at the start (November) and end (February) of the montanera or acorn mast-feeding season, when these are sustained fattened. At these two stages, acorn samples were taken from 20 oak trees (Q. ilex rotundifolia) that had been rejected by the pigs (onlyeating between 2 and 9 acorns from the ground underneath the tree) and from 20 oak trees that were actively sought out by the pigs (eating at least 40 acorns). The differences observed between the sought out and rejected acorns at the start and end of the montanera season are too great to be only a matter of chance, suggesting that Iberian pigs must form associationsbetweenvariableswhenchoosingtoeatorrejecttheacornsfromaspecificoaktree. The results show that pigs tend to select heavier acorns at the start of the montanera season, while at the end their selection is based more on the composition of the acorns. The greatest number of significant differences between the groups of acorns were found in the sought out acorns in November and February, owing to all the variables related with the composition of the acorns: crude fat (10.8±0.3 vs. 7.4±0.3), starch (58.3±1.0 vs. 50.3±0.4), sugars (6.8±0.4 vs. 13.2±0.3); most of the fatty acids; dimensions: length (38.1±0.8 vs. 31.9±0.7) and diameter

Brazil has various species of domestic animals, which developed from breeds brought by the Portuguese settlers soon after the discovery of the country. After being submitted to a long process of natural selection, these breeds present characteristics adapted to specific Brazilian environmental conditions, and are known as “criollo”, “local” or naturalized breeds. From the beginning of the 20th century, some exotic breeds, selected in temperate regions, have begun to be imported, and, although more productive, they do not have adaptive traits, such as resistance to disease and parasites found in the naturalized breeds. Even so, they gradually replaced the native breeds, to such an extent that the latter are in danger of extinction. To avoid further loss of this important genetic material, in 1983 the National Research Center for Genetic Resources and Biotechnology (Cenargen) of the Brazilian Agricultural Research Corporation (Embrapa) decided to include conservation of animal genetic resources among its priorities. The conservation activities have been conducted under the Brazilian Genetic Resources Network — Renargen, and is carried out by various research centres of Embrapa, universities and State research institutions, as well as by private farmers, with a single coordinator at national level, Cenargen. The in situ conservation of cattle, horses, buffaloes, donkeys, goats, sheep and pigs is being carried out by Conservation Nuclei, located in the animal's original habitat. Ex situ conservation is centred at the Brazilian Animal Germplasm Bank (AGB), kept at Cenargen. This is responsible for the storage of semen and embryos of various breeds of domestic animals threatened with extinction. Presently the AGB has almost 60,000 doses of semen and more than 250 embryos, as well as over 7000 DNA samples. An important challenge for this program is to increase awareness within the different segments of society in terms of the importance of the conservation of animal genetic resources. The development and evolution of Renargen and its efforts to facilitate the conservation of genetic resources of livestock in Brazil are described in this paper.

This paper is one in a series of studies treating the prerequisites for international use of nationally estimated breeding values (EBVs) of sport horse stallions. One prerequisite for effective use of national EBVs across countries (populations) is genetic connectedness among concerned populations. Thus, genetic connectedness between five sport horse populations from breeding organizations in Denmark (DWB), the Netherlands (KWPN), Sweden (SWB) and from the two German breeding organizations Hanover (Han) and Holstein (Holst) was studied. The number of stallions in common (NSC), genetic similarity (GS), variance of the differences between estimated country effects (CEV) in two organizations and correlation between estimates of country effects (CEC) were used as measures of the genetic connectedness between organizations. Stallions with progeny tested in performance tests for young horses in at least one of the five organizations were used. The material included 2457 stallions, born between 1952 and 1997, for which 49 446 progeny had been tested in the five breeding organizations. The numbers of stallions with offspring that had been tested in two, three, four and five of the participating organizations were 218, 58, 25 and 5, respectively. The material was arranged into groups according to birth-year of the stallion. Values for NSC, GS, CEV and CEC were calculated for each group to investigate whether there was any difference or trend in genetic connectedness over time. The same measures were also calculated for the whole data-set, considering all available information on pedigrees and progeny. Genetic connectedness was found between all participating organizations in all groups and grew stronger over time. The results were on a similar level to or better than comparable results for Icelandic horses and dairy cattle; they suggest that estimation of genetic correlations between similar traits tested in different organizations is feasible.

In this paper we discuss the use of genetic engineering in livestock production. We examine the main two different aspects of genetic engineering: cloning and transgenesis. After commenting what has been expected from both techniques in livestock production in the last 25 years, the practical difficulties for implementing cloning and transgenesis are examined. Apart from technical difficulties, problems derived from the detection of genetically superior animals and evaluation of the clones and the transgenic animals make these techniques less interesting than they appear to be. Most of the observed variability of the economically interesting traits is not genetic, genetic evaluation needs a large number of animals and cloning success will represent a serious loss of genetic variability and the loss of the flexibility needed for markets in constant evolution. There is a risk in transgenic animals of production of new intermediate biochemical products that may be toxic, allergenic or carcinogenic. The benefits produced by transgenic animals hitherto hardly justify this risk. The expectations that genetic engineering produced 25 years ago should be re-examined, considering the risks and the high investment required.

An experiment was carried out to study direct and indirect responses to selection in the Angora rabbit. There were two selection lines, one selected for high fleece weight and the other for low fleece weight. Data from 669 female rabbits born in 1994–2001 and having produced a total of 2923 harvest of wool were analysed to quantify the correlated responses to selection. By 2001, there had been eight cohorts of selection. The correlated responses analysed included compression, resilience, fleece quality traits (bristle and down length, average fibre diameter, comfort factor, bristle diameter) and secondary to primary follicle ratio ( S / P ). Genetic correlations were obtained by restricted maximum likelihood techniques. In response to selection, a positive difference of 0.92, 0.21 and 0.55 genetic standard deviation were observed for bristle length, comfort factor and S / P , respectively. No correlated response was observed on down length while negative differences of 1.00, 1.31, 0.38 and 0.50 genetic standard deviations were observed for compression, resilience, bristle diameter and average fibre diameter, respectively. Selection for increasing total fleece weight results in an increase of qualitative component traits of wool production in the French Angora rabbit. The quantitative traits were examined in the first (published) part of the paper.

This paper deals with the effects of hair coat characteristics on the sweating rate of Brazilian Braford cows and estimation of heritabilities and genetic correlations of these traits. Data ( n = 1607) on hair length, coat thickness, hair diameter, number of hairs per unit area, coat reflectance and sweating rate were recorded from heifers and cows of a commercial herd managed on range under extensive system. The data were analyzed considering the following effects on the model for hair coat traits: classes of sires and contemporary groups; linear effects of month and genotype; linear and quadratic effects of age. The effect of sire was important ( P P P P P P h 2 ) and broad ( H 2 ) sense for single-trait analyzes: hair thickness ( h 2 = 0.16; H 2 = 0.26); hair length ( h 2 = 0.18; H 2 = 0.39); number of hairs ( h 2 = 0.08 ± 0.07; H 2 = 0.08 ± 0.07); hair diameter ( h 2 = 0.12 ± 0.07; H 2 = 0.12 ± 0.07); coat reflectance ( h 2 = 0.30; H 2 = 0.42); and sweating rate ( h 2 = 0.10 ± 0.07; H 2 = 0.10 ± 0.07). In general, the genetic correlations between the adaptive traits were favorable as for the direction to select for adaptation in tropical environment; however, they presented high standard errors. The results of this study imply that hair coat characteristics and sweating ability are important for the adaptability to heat stress and they must be better studied and further considered for selection for genetic progress of adaptation in tropical environment.

The application of n -alkanes as faecal markers to estimate feed intake and apparent digestibility (DMD ap ) of equines and cattle was studied. Additionally, the effect of using different data on diet composition, known proportions of the diet components (DC1) and those estimated using the alkane markers (DC2), on the accuracy of intake and DMD ap estimates was evaluated. Six mature horses, divided in two groups of three animals (H1 and H2), and three adult non-lactating cows of Asturiana de los Valles breed ( C ) were housed in individual stalls. H1 and C groups were fed on a diet composed of Lolium perenne L . (70%) and heather (30%) and H2 received L. perenne (40%), heather (30%) and Ulex gallii Planchon (30%). The dietary component heather represented the field proportions of different plant species of heathland, namely Erica umbellata L., Erica cinerea L. and Calluna vulgaris L., at this experimental period. All animals received a daily dose of paper pellets containing C 24 , C 32 and C 36 n -alkanes as external markers with the purpose of using different n -alkane pairs of adjacent chain length for feed intake estimations. The results indicated that a period of 3 and 5 days was sufficient for these external markers to reach a steady concentration in faeces of cattle and equines, respectively. In contrast to the results obtained in cattle, the alkane faecal recovery in equines was unrelated to the carbon chain length. Diet composition only affected the faecal recovery of the alkanes C 24 ( P 31 ( P 32 ( P 36 ( P n -alkanes in the digesta. In equines, DMD ap estimates were not affected by the n -alkane (C 27 , C 29 , C 31 and C 33 ) used in the calculations, contrasting with the significant ( P ap estimates. Feed intake estimates were affected by the alkane pair used in the calculations in H1 ( P P C ( P P C . The differences from the known intake values were lower when using C 31 :C 32 alkane pair, overestimating intake in only an average of 4.5, 13.0 and 1.3% in H1, H2 and C , respectively, using DC1 or DC2. The results obtained in this study confirm the accuracy of the n -alkane markers to estimate simultaneously feed intake, apparent digestibility and diet composition of equines and cattle grazing these type vegetation communities.

In vitro digestibility analyses of feedstuffs and diets are integrated in the new Danish feed evaluation system for pigs. This system is based on potential physiological energy and standardised digestible amino acids. For characterisation of the energy value of actual batches of feedstuffs and complete diets for pigs, two different in vitro methods have been developed and proved to analyse precisely the digestibility of organic matter at faecal, as well as at ileal, level in the pigs. For characterisation of the protein value in the diet, table values for standardised digestibility of amino acids from the individual feedstuffs are used for calculation of their contribution to the amino acid recommendations for the specific pig category. The results in the present paper indicate that in vitro analyses for digestibility of crude protein in feedstuffs are a reliable tool for calculation of standardised ileal digestibility of the individual amino acids. Thus, the results may question the need for future experiments with surgically modified pigs for analysing ileal digestibility of amino acids in protein sources. Alternatively, in vitro digestibility analyses appear to have a general potential for a precise evaluation of amino acid digestibility in actual batches of feedstuffs and pig diets.

High dietary levels of soy oligosaccharides result in detrimental effects on intestinal and performance parameters of weaned piglets due to lack of endogenous enzymes for their hydrolysis. Intestinal fermentation of these components is connected with increased microbial activities and production of chyme, total volatile fatty acids and biogenic amines in the gut. The presence of soy oligosaccharides in piglets’ diets reduces nutrient digestibility and growth performance and increases the incidence of diarrhoea. The objective of this paper is to review the detrimental effects of oligosaccharides in soybean meal and to show the improvements in amino acids digestibility and growth performance in weaning piglets once these components are removed by ethanol extraction.