Review: Assessment of completeness of reporting in intervention studies using livestock: an example from pain mitigation interventions in neonatal piglets.

Accurate and complete reporting of study methods, results and interpretation are essential components for any scientific process, allowing end-users to evaluate the internal and external validity of a study. When animals are used in research, excellence in reporting is expected as a matter of continued ethical acceptability of animal use in the sciences. Our primary objective was to assess completeness of reporting for a series of studies relevant to mitigation of pain in neonatal piglets undergoing routine management procedures. Our second objective was to illustrate how authors can report the items in the Reporting guidElines For randomized controLled trials for livEstoCk and food safety (REFLECT) statement using examples from the animal welfare science literature. A total of 52 studies from 40 articles were evaluated using a modified REFLECT statement. No single study reported all REFLECT checklist items. Seven studies reported specific objectives with testable hypotheses. Six studies identified primary or secondary outcomes. Randomization and blinding were considered to be partially reported in 21 and 18 studies, respectively. No studies reported the rationale for sample sizes. Several studies failed to report key design features such as units for measurement, means, standard deviations, standard errors for continuous outcomes or comparative characteristics for categorical outcomes expressed as either rates or proportions. In the discipline of animal welfare science, authors, reviewers and editors are encouraged to use available reporting guidelines to ensure that scientific methods and results are adequately described and free of misrepresentations and inaccuracies. Complete and accurate reporting increases the ability to apply the results of studies to the decision-making process and prevent wastage of financial and animal resources.

H/L ratio as a measurement of stress in laying hens - methodology and reliability.

Measuring the ratio of heterophils and lymphocytes (H/L) in response to different stressors is a standard tool for assessing long-term stress in laying hens but detailed information on the reliability of measurements, measurement techniques and methods, and absolute cell counts is often lacking. Laying hens offered different sites of the nest boxes at different ages were compared in a two-treatment crossover experiment to provide detailed information on the procedure for measuring and the difficulties in the interpretation of H/L ratios in commercial conditions. H/L ratios were pen-specific and depended on the age and aviary system. There was no effect for the position of the nest. Heterophiles and lymphocytes were not correlated within individuals. Absolute cell counts differed in the number of heterophiles and lymphocytes and H/L ratios, whereas absolute leucocyte counts between individuals were similar. The reliability of the method using relative cell counts was good, yielding a correlation coefficient between double counts of r > 0.9. It was concluded that population-based reference values may not be sensitive enough to detect individual stress reactions and that the H/L ratio as an indicator of stress under commercial conditions may not be useful because of confounding factors and that other, non-invasive, measurements should be adopted.

Pain management in the neonatal piglet during routine management procedures. Part 2: grading the quality of evidence and the strength of recommendations.

Piglets reared in swine production in the USA undergo painful procedures that include castration, tail docking, teeth clipping, and identification with ear notching or tagging. These procedures are usually performed without pain mitigation. The objective of this project was to develop recommendations for pain mitigation in 1- to 28-day-old piglets undergoing these procedures. The National Pork Board funded project to develop recommendations for pain mitigation in piglets. Recommendation development followed a defined multi-step process that included an evidence summary and estimates of the efficacies of interventions. The results of a systematic review of the interventions were reported in a companion paper. This manuscript describes the recommendation development process and the final recommendations. Recommendations were developed for three interventions (CO2/O2 general anesthesia, non-steroidal anti-inflammatory drugs (NSAIDs), and lidocaine) for use during castration. The ability to make strong recommendations was limited by low-quality evidence and strong certainty about variation in stakeholder values and preferences. The panel strongly recommended against the use of a CO2/O2 general anesthesia mixture, weakly recommended for the use of NSAIDs and weakly recommended against the use of lidocaine for pain mitigation during castration of 1- to 28-day-old piglets.

Nest use is influenced by the positions of nests and drinkers in aviaries.

The influence of the nest location and the placement of nipple drinkers on nest use by laying hens in a commercial aviary was assessed. Twenty pens in a laying hen house were equipped with the same commercial aviary system, but the pens differed in the nest location and the placement of nipple drinkers. Nests were placed along the walls in 10 pens, and nipple drinkers were installed in front of the nests in 5 of these pens. The other 10 pens were equipped with nests placed on a tier within the aviary (integrated nests). Nipple drinkers were installed in front of the nests in 5 of these pens. A total of 225 Lohmann Selected Leghorns were housed per pen. The hens were offered 4 nests per pen: 2 facing the service corridor of the laying hen house and 2 facing the outdoor area. The numbers of nest eggs and mislaid eggs were counted daily per pen. At 25, 36, and 43 wk of age, the nest platforms were videotaped and the behavior of laying hens in front of the nests was analyzed. The nest location affected the stationary and locomotive behaviors in front of the nests. Hens in front of the integrated nests and the nests with drinkers displayed more stationary behaviors than hens in front of wall-placed nests or nests without drinkers. No difference in the number of nest eggs could be detected, but the integration of the nests inside the aviary led to a more even distribution of hens while nest searching. In the pens with wall-placed nests, significantly more hens laid eggs in the nests at the wall near the service corridor than at the wall near the outdoor area. Due to this imbalance, crowding in front of the preferred nests occurred and pushing and agonistic interactions on the nest platforms were significantly more frequent. Placement of nipple drinkers in front of nests had no effect on the number of eggs laid in those nests.

Impact of general injection anaesthesia and analgesia on post-castration behaviour and teat order of piglets.

Injection anaesthesia with a combination of ketamine and azaperone (K/A) is discussed as a painless alternative to commonly used non-anaesthetized castration. To protect anaesthetized piglets from being crushed, they have to be separated from the sow for 3 h following castration. The aim of this study was to test if this separation and the different treatments would affect short-term behaviour after castration (3 to 6 h after castration) as well as weight gain. Piglets were 5 to 7 days old. Treatment Group 1 received a combination of anaesthesia and analgesia (n = 29, ketamine: 25 mg/kg BW; azaperone: 2 mg/kg BW; meloxicam: 0.4 mg/kg BW), Group 2 received only analgesia (n = 24) and Group 3 received no medication (n = 29). Behaviour and suckling order were compared for a 3 h period the day before castration and after castration. A significantly higher number of teats used by anaesthetized piglets (P = 0.004) suggests a decrease in suckling order stability. There were significant treatment effects between all three groups in the time spent at the sow's teat, with an increase in Group 2 (+69%), decrease in Group 1 (-28%), whereas the control Group 3 (+2%) almost remained unchanged. The anaesthetized piglets showed an increase in the time spent active away from the sow after castration of almost 200% (Groups 2 and 3: ∼50%, P < 0.001). However, no significant treatment effect was seen for weight gain. The results suggest that analgesia has an effect on behaviour, perhaps due to less post-castration pain. This advantage is not apparent for animals receiving additional anaesthesia, probably because of impaired coordination. Although the behavioural changes did not affect weight gain significantly, a decrease in suckling order stability indicates a certain degree of stress due to fighting over teat positions as a consequence of separation. Thus, post-castration behaviour must be taken into account when evaluating alternative castration methods.

Analysis of ordered categorical data with threshold models exemplified by plumage damage scores from laying hens differing in their genotype and rearing environment.

Plumage damage scores (PDS) were assessed in laying hens of 2 genotypes (Lohmann Tradition and Lohmann Silver) at the 45th and 70th weeks of age, with scores ranging from zero (no damage) to 6 (completely denuded). This ordinally scaled categorical characteristic was recorded from different body regions of 365 hens that had experienced different housing environments (2 enrichment levels) during their rearing and laying periods. The so-called threshold model is an option for analyzing repeated ordered categorical data from individual animals. This model represents a generalized linear mixed model if the linear predictor additionally includes the animal as a random effect. This paper is intended to fill the gap between the theoretical aspects of generalized linear mixed models and their practical application in animal science. A cumulative probit model was adapted for analyzing plumage damage. The variation among birds was considered as a random effect for the analysis of cumulative probabilities. The numerical implementation of the methodology was done based on the NLMIXED procedure of the SAS statistical program. A threshold model with inhomogeneous residual variances for the latent variable was used because less plumage damages were observed up to the 45th week of age compared to the 70th week of age. Differences in PDS were evident between genotypes, age, and enrichment levels during housing periods. However, neither of the 2 enriched environments proved consistent superiority or inferiority across all traits. Major plumage damage (PDS larger than or equal to 5) was observed for the breast region in 56.6% of all birds with the Lohmann Tradition genotype and in 34.4% with the Lohmann Silver genotype when we look at the mean over all treatments. The most severe plumage damage was observed at the 70th week of age for the traits breast and housing environment without additional enrichment.

mRNA abundance of adiponectin and its receptors, leptin and visfatin and of G-protein coupled receptor 41 in five different fat depots from sheep.

Adipose tissue (AT) expresses adipokines, which are involved in the regulation of energy expenditure, lipid metabolism and insulin sensitivity. Visceral (v.c.) and subcutaneous (s.c.) depots largely differ concerning their metabolic characteristics as to the control of lipolysis and the sensitivity to insulin. The adipokines adiponectin, leptin and visfatin influence lipolysis and insulin sensitivity. Signalling by G-protein coupled receptor 41 (GPR 41) stimulates leptin release via activation by short-chain fatty acids. We hypothesized that the metabolic differences between v.c. and s.c. fat depots may also apply to the expression of adiponectin, its receptors, leptin, visfatin, insulin receptor (IR) and GPR 41. Therefore, we aimed to compare the mRNA expression of adiponectin, leptin and visfatin, of the adiponectin receptors 1 and 2 (AdipoR1/2) and IR as well of GPR 41 between several s.c. and v.c. fat depots in sheep. Samples from 10 rams were collected at slaughter (40 kg BW) from three s.c. depots, i.e. close to sternum (s.c.S), close to withers (s.c.W), and at the base of tail (s.c.T), and from two v.c. depots, i.e. from perirenal (v.c.P) and omental (v.c.O) fat. The mRNAs of both adiponectin receptors, as well as IR and putative GPR 41, were higher expressed in v.c. fat than in s.c. fat (p ≤ 0.05). Leptin mRNA abundance was greater in s.c. than in v.c. fat (mean ± SEM: s.c.: 2.55 ± 0.81; v.c.: 0.66 ± 0.21) and also differed among the five separately measured fat depots. Our results show differences in mRNA abundance for leptin, AdipoR1 and R2, as well as for IR and GPR 41 in s.c. compared with v.c. fat, thus confirming the need for individual consideration of distinct fat depots, when aiming to characterize adipose functions in ruminants.

Animal welfare implications of surgical castration and its alternatives in pigs.

This paper constitutes a review on the welfare aspects of piglet castration that considers the scientific literature published after 2004. Castrating during the neonatal period (1 to 3 days of age) is clearly painful. In addition, inflammatory processes may take place at the sites of incision, thus adding further pain to the procedure. Surgical castration with general and local anaesthesia, in combination with long-term analgesia, has been shown to reduce pain but the additional handling and injection of the anaesthetic, the effectiveness and limited safety margins have to be thoroughly evaluated. Raising entire males during the whole fattening period or immunocastration of males towards the end of the fattening period are other alternatives with welfare benefits in young pigs compared to current surgical castration, but with some potential welfare drawbacks regarding handling stress and behaviour during fattening. Based on the current knowledge, it can be concluded that sperm sexing and raising entire males after genetic control of boar taint are potentially preferable alternatives to current practices, but need further research, as these methods are not yet available.

Role of loose feathers on the development of feather pecking in laying hens.

1. The effect of the presence of loose feathers (on the floor) on the behaviour and plumage condition of laying hens (Lohmann Silver, LS) was studied during the rearing and laying periods. 2. From one day old, 60 birds in each of 4 straw-bedded pens (n = 240 in total) with 6.5 birds/m(2) were either kept under conventional rearing and management conditions (CT: control group with feathers on the floor; n = 120) or in pens from which the feathers were collected from the floor 4 times/week (FR: feathers removed; n = 120). Fifty birds from each of these 4 groups (n = 200 in total) were randomly selected at the age of 16 weeks and allocated to 4 identical pens in a poultry layer house (PH; with perches and 1/3 slatted floor) with access to an outside area (winter garden, WG) at a stocking density of 6 birds/m(2) in both PH and WG. 3. Observations on feather pecking and other behaviours (feeding, drinking, preening, standing, sitting, foraging, moving and dust bathing) were carried out at 8 ages: 6, 10, 15 (rearing period), 20, 25, 30, 35 and 40 weeks (laying period). Feather scoring was carried out at 15, 32 and 39 weeks of age. 4. There were no differences in feather pecking rates, forms (gentle, severe and aggressive pecks) as well as in the plumage condition between groups at the end of the rearing period. 5. Birds in the FR group exhibited lower rates and less severe feather pecking during the laying period. Accordingly, birds in the control group had worse feather condition at 32 and 39 weeks of age. Feather pecking rates within groups were, in general, greater in the afternoon compared to the morning periods. Birds in the control group were more active in walking. 6. Wings, rump, tail and back were the main targets for feather pecking. The majority of feather pecking occurred on the floor (66%) followed by feeding area (26%), perches (4%) and slats (4%). 7. Our results suggest that loose feathers on the floor may play an important role in the development and severity of feather pecking behaviour in laying hens and support the hypothesis (McKeegan and Savory, 1999) that feather pecking can be viewed as redirected foraging behaviour.

The relationships between leptin concentrations and body fat reserves in lambs are reduced by short-term fasting.

Feed deprivation decreases plasma leptin concentrations depending on the amount of body fat reserves. While a greater response was observed in lean than in fat humans and rats, a few results for ruminants are inconsistent. The objective of this study was to determine the influence of feed deprivation on plasma leptin concentration in growing lambs with different body fat reserves and on the relationship between leptin and fatness. In addition, we included other hormones (growth hormone, GH; insulin-like growth factor-I, IGF-I and insulin) involved in tissue development. Thirty male lambs of 40 kg live weight were used. Blood was sampled before and after a fasting period of 24 h. The lambs were slaughtered and dissected into several fat and lean tissues. Feed deprivation reduced plasma leptin by an average of 34.6% (p < 0.001). Obese lambs exhibited a greater decline of leptin than lean lambs (2.50 vs. 1.36 ng/ml, p < 0.05). The correlations between leptin and several fat tissues were lower in those lambs than that were fasted. This indicates that leptin concentrations after short-term fasting scarcely reflect the extent of body fat reserves but reflect more the actual metabolic situation. Body fat did not significantly influence the response of GH, IGF-I and insulin to fasting in most cases.

Plasma leptin in growing lambs as a potential predictor for carcass composition and daily gain.

Leptin is an adipocyte derived hormone and correlates highly to the extent of body fat tissue. The aim of this study was to determine if leptin could serve as an early predictor for carcass composition and final growth rate in lambs with special emphasis on size and cellularity of the different body fat depots. Thirty intact male ad libitum fed lambs were blood sampled at 20, 25, 30, 35, and 40kg live weight. After slaughtering at 40kg, lean and the visceral, subcutaneous and intermuscular fat were measured by dissection. The fat cell diameter was determined in subcutaneous and perirenal fat. Average daily gain from birth to slaughter correlated to leptin only at 30 and 35kg live weight (r=-0.56 and -0.61, P<0.01) and thus leptin cannot be regarded as a suitable early predictor for growth rate. That goes for the prediction of subcutaneous and intermuscular fat, too; because no relationships were detected between early leptin concentrations and the amount of these tissues. Leptin concentrations measured just before slaughter were related to all fat tissues except the pelvic and intramuscular fat. Among the visceral fat depots, omental fat expressed the highest correlations to leptin (r=0.60, P<0.001). Additionally, leptin concentrations at 35 and 40kg live weight increased with increasing fat cell diameters (r=0.38, P<0.05 to r=0.59, P<0.001). This study indicates that leptin concentration measured in the slaughter weight range has the greatest potential to assess body fat content, whereas an earlier prediction does not seem to be feasible. Further studies should clarify if these results are reproducible for other breeds or species.

Relationship between plasma leptin concentrations and carcass composition in fattening mutton: a comparison with ultrasound results.

Positive relationships between circulating leptin concentrations and body fat content have been established in sheep when covering a rather broad range of age and/or body weight. The usefulness of leptin measurements for predicting carcass fat has yet to be evaluated specifically in fattening lambs. We therefore measured plasma leptin concentrations in 56 male lambs half and half Merino Mutton and Blackheaded Mutton. Subcutaneous fat thickness was measured by ultrasound 1 day before the lambs were slaughtered at 35 or 45 kg live weight. Carcass composition was determined by tissue dissection. The coefficients of correlations between leptin and the different amounts in fat depots ranged from 0.40 to 0.56 within the two live weight groups, and from 0.53 to 0.64 when taking the two groups together. Carcass fat percentage was estimated by leptin concentrations with the same accuracy (R2 = 0.34) as with ultrasound fat thickness. The accuracy was higher for leptin in the 35 kg-group whereas the accuracy was higher for ultrasound fat thickness in the 45 kg-group (R2 = 0.26 vs. 0.31). A combination of leptin and ultrasound fat thickness clearly enhanced the precision of estimation in all groups. Further investigations on the influence of factors such as breed, gender, duration of feed withdrawal or photoperiod on the association between leptin and carcass composition are necessary before the suitability of plasma leptin concentration for practical application can be evaluated.

Prediction of lamb carcass composition by impedance spectroscopy.

The objective of this study was to compare impedance spectroscopy with resistance measurements at a single frequency (50 kHz) for the prediction of lamb carcass composition. The impedance spectrum is usually recorded by measuring the complex impedance at various frequencies (frequency domain); however, in this study, we also applied the faster and simpler measurement in the time domain (application of a current step and measurement of the voltage response). The study was carried out on 24 male, German Black-headed Mutton lambs with an average BW of 45 kg. Frequency- and time domain-based impedance measurements were collected at 20 min and 24 h postmortem with different electrode placements. Real and imaginary parts at various frequencies were calculated from the locus diagram. Left sides were dissected into lean, fat, and bone, and right sides were ground to determine actual carcass composition. Crude fat, crude protein, and moisture were chemically analyzed on ground samples. Frequency- and time domain-based measurements did not provide the same absolute impedance values; however, the high correlations (P < 0.001) between these methods for the "real parts" showed that they ranked individuals in the same order. Most of the time domain data correlated higher to carcass composition than did the frequency domain data. The real parts of impedance showed correlations between -0.37 (P > 0.05) and -0.74 (P < 0.001) to water, crude fat, lean, and fatty tissue, whereas the relations to CP were much lower (from 0.00 to -0.47, P < 0.05). Electrode placements at different locations did not substantially improve the correlations with carcass composition. The "imaginary parts" of impedance were not suitable for the prediction of carcass composition. The highest accuracy (R2 = 0.66) was reached for the estimation of crude fat percentage by a regression equation with the time domain-based impedance measured at 24 h postmortem. Furthermore, there was not a clear superiority of measurements in a wide frequency range over a single frequency measurement at 50 kHz for the prediction of carcass composition. Even though we calculated the impedance at 50 kHz based on the locus diagram, which allowed for a high precision for predicting this impedance trait, single-frequency impedance devices typically used in practice cannot record the locus diagram and, therefore, exhibit a greater amount of uncertainty.

Outdoor use, tonic immobility, heterophil/lymphocyte ratio and feather condition in free-range laying hens of different genotype.

1. Movement (frequency of changes) between inside and outside housing areas, time spent in each area, tonic immobility (TI) and differential blood cell counts were studied in relation to feather condition in laying hens of two genotypes, white (LSL) and brown (LT). 2. From 18 weeks of age, LSL and LT were kept in 4 groups of 50 birds in a poultry house with passages to a roofed scratching room and a grassland area with a stocking density of one bird/10 m2. 3. All birds had transponders to record the movements of each hen between inside and outside areas and the time spent in each area during 24 h. Feather scoring was carried out at 6 ages from 20 to 48 weeks. At 44 weeks of age, TI reactions of 40 hens (20 from each genotype) were quantified and blood smears from 20 hens (10 from each genotype) were analysed for differential leucocyte counts. 4. LSL hens moved more frequently to outdoor areas than LT hens (44.66 vs 28.78 least square/d). However, the proportion of time spent on grassland was greater in LT than in LSL hens, whereas time (%) spent by LT hens in the roofed scratching area was less than for LSI hens. 5. In LT hens TI was shorter while heterophil/lymphocyte ratio and basophilia were greater than in LSL hens. 6. Total body feather score was poorer in LSL than in LT hens. Incidence of footpad inflammation was higher in LSL than LT hens. 7. There was a positive association between TI and footpad inflammation. The percentage of time spent on grassland and feather damage were inversely correlated. 8. More movement between the areas, as in LSL hens, was positively associated with fearfulness, whereas long periods on grassland, as in LT hens, were associated with indicators of increased stress. The negative correlation between feather damage and time spent outside suggests that feather pecking risk decreases in birds attracted to grassland.

[Animal welfare-conforming fallow deer farming in Germany--a review]. / Tierschutzkonforme Damwildhaltung in Deutschland--eine Ubersicht.

Fallow deer farming for venison production on pasture and fallow land has gained importance in Germany during recent years. As fallow deer farming constitutes a relatively young farming practice, many questions concerning a welfare-conforming and ecologically sound keeping of fallow deer are still open. Based on the recommendations on the keeping of fallow deer in enclosures for the purpose of venison meat production including by-products from 2 November 1979, a critical comparative review considering the current knowledge from research and practical deer farming experience was conducted. Recommendations on measures for breeding management and administration (statistics on farms and stocks, security and control of enclosures, training and experience of stockperson, practical skills for immobilisation and killing) are proposed. The cultivation goals for the care of landscape by fallow deer farming in protected areas need to be defined precisely. Due to infection risk, mixed herds with domesticated ruminants are not recommended. Potential progress can be foreseen in preventive health measures (control of endoparasites) and by appropriate feeding and water supply, considering feeding and drinking place design, feeding behaviour and water needs. The knowledge on handling and immobilisation methods should also be applied to small herd sizes. More research is needed on transportation of fallow deer.

[Noise in animal housing--a review with special reference to pig housing]. / Lärm in der Nutztierhaltung--eine Ubersicht, unter besonderer Berücksichtigung der Schweinehaltung.

The interpretation of research on noise assessment in animal housing is difficult as goals and methodology of assessment differ substantially between studies. Besides the differences in housing conditions and technology used for measuring noise, a lack of knowledge exists for intra- and interspecies communication, hearing ability and assessment of detrimental consequences following noise exposure. Due to the development of intensive production systems, pigs in all stages of housing are exposed to monotonous chronic noise as well as to a variety of intense noise events. The intention of this review is to document and compare the results of previous studies on noise assessment, in particular housing situations and to demonstrate the impact and significance of the noise problem for farm animal welfare, housing, design and management.

[Behavior of piglets during castration with and without local anesthesia]. / Verhalten von Ferkeln während der Kastration mit und ohne Lokalanästhesie.

According to the German welfare act of 1998 (Art.5(3)1.), surgical castration of up to 4 wk old pigs does not require anaesthesia. However, the application of a local anaesthesia is discussed in the context of pain related responses to this procedure. In these experiments, effects of different methods of application on the behaviour of piglets during castration are evaluated as a contribution to the welfare assessment of this procedure. A total of 36 piglets between 10 and 14 days of age were castrated with and without a local anaesthesia. Local anaesthesia with Lidocaine 2% was applied in two ways: a) via intratesticular (i.t.) injection and b) intratesticular injection combined with subcutaneous (s.c.) infiltration of the anaesthetic into the tissue around the spermatic cord. The assessment of pain was performed on the basis of vocalisations and resistance movements of the animals during the procedure. Local anaesthesia resulted in a reduction of the relative proportion of resistance movements from the entire period of fixation (castration with i.t. anaesthesia 12.73%, with i.t. and s.c. anaesthesia 14.50% or without a local anaesthesia 18.96%; P < 0.05). In particular, local anaesthesia resulted in a reduction of resistance movements during the cutting of the spermatic cord. The response of piglets to additional skin stimulation of the scrotum was not different between the three treatments.

[Voluntary testing procedures of farm animal housing equipment according to the Animal Welfare Act of 1998]. / Freiwilliges Prüfverfahren für Stalleinrichtungen entsprechend dem novellierten Tierschutzgesetz von 1998.

Before its broad application in practice, housing equipment should be tested, in particular with regard to animal welfare. The differing positions of the German Federal Council (Bundesrat) and the German Federal Parliament (Bundestag), whether such testing should be mandatory or voluntary, have been conciliated in the amended animal welfare act by empowering the Federal Ministry of Food, Agriculture and Fisheries (BML) to fix official standards for voluntary testing procedures by regulation. On request of the BML, a report as scientific basis for a draft regulation is currently prepared by the scientific animal welfare committee of the German Agricultural Society (DLG). The scientific animal welfare committee has been appointed by the DLG in order to provide support in the effort to strengthen animal welfare aspects in the DLG-utility testing procedure of housing equipment, which is in place since 1953. The committee elaborates standards concerning testing methods, assessment criteria and the necessary size of investigations. As required, the scientific animal welfare committee may support the DLG-testing bodies in the implementation of the animal welfare part of the testing procedure. It will, moreover, be involved in the welfare assessment based on the testing results. The amendments of the already established testing procedure will help to fulfill the general requirements on an acceptable animal welfare testing procedure. While keeping in mind that there are certain limits in what can be achieved by a voluntary testing procedure, the enhanced consideration of animal welfare aspects within the DLG-utility testing procedure has the advantage to be relatively unbureaucratic and in line with EU legislation, and is, therefore, an appropriate tool for a contibrution to improved animal welfare in livestock housing.

Impact of feeding regimen on behavioral and physiological indicators for feeding motivation and satiety, immune function, and performance of gestating sows.

The effect of daily or interval (every 3 d) feeding on body weight change, blood glucose and cholecystokinin (CCK) concentrations, immune function, and behavioral activity were determined during the gestation period of sows. Sows were fed a corn-soybean meal diet either 2 kg daily or 6 kg once every 3rd d (interval). Body weight changes for the 42-d trial period were not different (P > .05) between regimens. Blood glucose concentrations were similar before feeding (P > .05). Two hours after feeding, glucose concentrations increased in interval-fed sows but not in daily-fed sows (P < .05). Premeal plasma CCK concentrations were greater for daily-fed sows than for interval-fed sows (P < .05). The CCK concentrations in sows of both regimens increased after feeding above premeal levels (P < .05), and interval-fed sows exhibited higher concentrations than daily-fed sows (P < .05). Immune function as evaluated through mitogen-induced proliferation of T cells was greater in daily-fed sows than in interval-fed sows (P < .05). Daily-fed sows were more active overall and on any given day than interval-fed sows (P < .05) and thus seemed to expend more energy. Further, daily-fed sows exhibited higher levels of mouth-based activities (i.e., sham chewing, licking, appetitive and consummatory feeding behavior, and excess drinking) than sows restricted to consumption of one large meal every 3rd d. These indicators suggest that feeding motivation significantly affected overall performance of sows. This study emphasizes the need for evaluating the impact of feeding regimens and meal size on feeding motivation and, ultimately, on the well-being of the gestating sows.