Ruminant husbandry constitutes the most important source of anthropogenic methane (CH4). In addition to enteric (animal-derived) CH4, excreta are another source of CH4, especially when stored anaerobically. Increasing the proportion of dietary concentrate is often considered as the primary CH4 mitigation option. However, it is unclear whether this is still valid when diets to be compared are energy-balanced. In addition, non-structural carbohydrates and side effects on nitrogen (N) emissions may be important. In this experiment, diet types representing either forage-only or mixed diets were examined for their effects on CH4 and N emissions from animals and their slurries in 18 lactating cows. Apart from a hay-only diet, treatments included two mixed diets consisting of maize stover, pelleted whole maize plants and gluten or barley straw and grain and soy bean meal. The diets were balanced in crude protein and net energy for lactation. After adaptation, data and samples were collected for 8 days including a 2-day CH4 measurement in respiratory chambers. Faeces and urine, combined proportionately according to excretion, were used to determine slurry-derived CH4 and N emissions. Slurry was stored for 15 weeks at either 14°C or 27°C, and temperatures were classified as ‘cool’ and ‘warm’, respectively. The low-starch hay-only diet had high organic matter and fibre digestibility and proved to be equally effective on the cows’ performance as mixed diets. The enteric CH4 formation remained unaffected by the diet except when related to digested fibre. In this case emission was lowest with the hay-only diet (61 v. 88 to 101 g CH4/kg digested NDF). Feeding the hay diet resulted in the highest slurry-CH4 production after 7 weeks of storage at 14°C and 27°C, and after 15 weeks at 14°C. CH4 emissions were, in general, about 10-fold higher at 27°C compared with 14°C but only after 15 weeks of storage. Urinary N losses were highest with the barley diet and lowest with the maize diet. There was a trend towards similar differences in N losses from the slurry of these cows (significant at 14°C). However, contrary to CH4, slurry-N emissions seemed to be temperature-independent. In conclusion, energetically balanced diets proved to be widely equivalent in their emission potential when combining animal and their slurry, this even at a clearly differing forage : concentrate ratio. The variation in CH4 emission from slurry stored shortly or at cold temperature for 15 weeks was of low importance as such conditions did not support methanogenesis in slurry anyway.

Weaning of livestock mammals is often associated with digestive problems related to profound changes in the physiology of the gastrointestinal tract. This study was undertaken to study the developmental changes in the gastrointestinal tract of mink kits during the period of 34 to 59 days of age. Twenty-four mink kits from eight litters were included in the experiment. The dams and their litters were kept under standard farm conditions. The dams and the kits were fed a diet consisting of 48.1% protein, 40.7% fat and 11.1% carbohydrate of metabolizable energy. The mink kits were weaned at 42 days of age. At 34, 47 and 59 days of age, one male mink kit from each litter was euthanized. The activity of amylase, trypsin, chymotrypsin and lipase in the pancreatic tissue increased during the experimental period, whereas the activity of carboxyl ester hydrolase remained constant. The vitamin E concentration in plasma was stable from 34 to 59 days of age, whereas the concentration decreased in the liver. The stereochemical composition of α-tocopherol showed a steep decrease in the concentration of the biologically most active natural isomer in both plasma and liver through the whole weaning period, whereas the biologically less active 2S isomers showed a clear increase. The concentration of bile salts did not change during the experimental period. The villous height increased in the proximal part of the small intestine and decreased in the distal part, whereas the crypt depth was doubled in both the proximal and distal part of the small intestine. The mucin-staining area on the villi was markedly reduced during the experimental period but no change in the mucin-staining area in the crypts was observed.

The first limiting nutrients in typical laying hen diets are the sulphur-containing amino acids and, in particular, methionine. To fulfil the birds’ recommended requirement, conventional diets are supplemented with synthetic methionine. As this is not allowed in organic production it becomes very important to have access to alternative high-quality protein feed ingredients. An experiment was performed to evaluate the possibility to compose a diet with 100% organically approved feed ingredients using mussel meal as a major source of methionine. The experiment included 678 Lohman Selected Leghorn (LSL) and 678 Hyline White, W-98, layers during 20 to 72 weeks of age. There were 12 aviary pens with 113 birds in each. The birds were fed one of the two experimental diets containing either 3.5% or 7% dried mussel meat meal or a commercial organic diet from a Swedish feed manufacturer for comparison. Production and mortality were recorded daily per group, and egg weight was recorded once weekly. At 33, 55 and 70 weeks, 10 eggs from each treatment group were collected and analysed for internal egg quality. Diets had no significant effect on laying percentage, egg mass, feed intake, feed conversion ratio, mortality, bird live weight or proportion misplaced, cracked or dirty eggs. Egg quality, that is, shell deformation, shell breaking strength, albumen height, shell percentage and proportion of blood and meat spots were also unaffected. There was a significant difference in egg yolk pigmentation, that is, the egg yolk was more coloured when feeding 7% mussel meal compared with the other diets. Hyline hens had lower feed intake and laying percentage, and higher egg weight, but lower egg mass production than LSL birds. The age of the birds influenced all egg quality traits except for meat and blood spots. The dry matter of the excreta was significantly lower for both genotypes fed the 7% mussel meal diet. These results indicate that mussels may be a high-quality protein source and may replace fishmeal in organic diets for layers.

Cattle breeds indigenous to Africa (Sanga) compare favourably to Bos indicus breeds with regard to adaptation to harsh environments. This study compared the meat quality of three Sanga breeds (Nguni, Tuli and Drakensberger), a Sanga-related breed (Bonsmara) and a B. indicus breed (Brahman) and supported these results with biochemical and histological measurements on the M. longissimus lumborum. Twelve young grain-fed steers of each breed were slaughtered and carcasses were electrically stimulated. All Sanga (and related) breeds, with the exception of the Tuli, had lower Warner–Bratzler shear force (SF) values at 2 and 21 days post mortem compared with the BR (P < 0.05). Measurements related to the calcium-dependent protease system and myofibrillar fragmentation explained the bulk of the variation among breeds, whereas variation in fibre type, sarcomere length and connective tissue properties gave less convincing support. With the exception of the Tuli, Sanga and Sanga-related breeds produced more tender (according to SF) meat than BR, mainly due to favourable calpain-to-calpastatin ratios. Small differences in colour, drip loss and cooking properties were found among breeds (P < 0.05).

Theory that successfully explains the magnitude and range of estimates of protein retention (PR) efficiency from the cost of turnover of existing protein indicates that conventional curves for growth description are inappropriate for protein growth. A solution to this problem is found in the consideration that the rate-limiting steps for protein synthesis (PS) and breakdown are likely to be associated with the diffusion of metabolites in and between cells. The algebraic scaling of nuclear and cellular diffusion capacity with tissue or total body protein leads to a parameterization of the primal differential equation for PR (kg/day) based on two terms representing PS and breakdown, viz.where c is an arbitrary constant, Q is the proportion of nuclei active in cell growth or division in a tissue or the whole body, α is the limit mass for protein (P, kg) in a tissue or the whole body, the power X + Z represents the rate-limiting steps in protein breakdown and Y is the power of the relationship between cell volume and the amount of tissue protein. For the whole body, the contribution of the different tissues should be weighted in proportion to their PS rates with, on average, Y = 1/2. The constant 4/9 arises from the scaling of the specific diffusion rate of DNA activator precursors from nuclear dimensions and from the relationship between nuclear and cell volume. Experimental evidence on protein breakdown rate as well as protein and body mass points of inflection indicates that the range of theoretically possible numerical values of the rate-limiting powers X + Z = (i + 3)/9 for i = 1, 2, … ,12 seems adequate for the description of the range of observed whole body protein and body mass growth patterns for mammals. Q = 1 represents maximal protein retention, and for 0 < Q < 1, experimental evidence exists in support of a theoretical relationship between Q and food ingestion. The conclusion follows that some knowledge of the protein limit mass (α) and of the point of inflection (related to X + Z) is the main requirement for the application of the theory for description and prediction in animal nutrition and breeding.

We developed a method for studying the synchrony of behaviour based on calculations of overdispersion of a binomial process. The lying behaviour of cows was investigated under two different housing units inside the same barn. The first unit housed 30 cows undergoing conventional milking and the second unit housed 27 cows undergoing automatic milking. The lying behaviour of the cows was observed over 3 weeks in 12 periods of 6 h each. Every 5 min, we counted the number of cows lying down in the cubicles. As external cues, like feeding and conventional milking, can promote synchrony in dairy cows, we expected that cows conventionally milked would show more behavioural synchrony than automatically milked cows. Cows lied down synchronously in both units (overdispersion 1.67, P < 0.01). Lying synchrony tended to be slightly bigger in automatically than in conventionally milked cows (overdispersion 1.76 v. 1.58, P = 0.09), although the proportion of cows lying down was on average greater in conventionally than in automatically milked cows (60.7% v. 45.6%). This suggests that synchronized lying behaviour in cows is a constant phenomenon that depends on social facilitation rather than on external cues. The overdispersion index appears to be a useful tool for studying the synchrony of animal behaviour when observations are made at the group level.

A 2 × 2 factorial experiment was conducted to investigate the effects of cereal type (barley v. oat) and exogenous enzyme supplementation (with or without) on intestinal fermentation, and on indole and skatole levels in the intestinal content and the adipose tissue in finisher boars. The experimental treatments were as follows: (i) barley-based diet, (ii) barley-based diet with enzyme supplement, (iii) oat-based diet and (iv) oat-based diet with enzyme supplement. The enzyme supplement contained endo-1,3(4)-β-glucanase (EC 3.2.1.6) and endo-1,4-β-xylanase (EC 3.2.1.8). The animals were fed ad libitum for 45 days from 76.0 to 113.6 kg live weight. Feeding barley-based diets led to higher (P < 0.05) total volatile fatty acids concentrations in the large intestine. Proportions of propionic- and butyric-acids were higher and that of acetic acid lower in digesta from barley-based in comparison to oat-based diets (P < 0.001). Consequently, pH in the large intestine was higher after feeding oat-based in comparison to barley-based diets. Animals fed unsupplemented oat-based diet had higher (P < 0.01) indole concentrations in the digesta from the proximal colon than those fed barley-based diets. Feeding oat-based diets led to lower (P < 0.01) skatole and higher (P < 0.001) indole concentrations in the digesta from the terminal colon than barley-based diets. skatole concentrations in the adipose tissue did not differ (P > 0.05) between the experimental treatments. Pigs offered the barley-based diets had lower (P < 0.001) indole concentrations in the adipose tissue compared with those fed the oat-based diet. In conclusion, barley-based diets were more efficient than oat-based diets in limiting concentrations of indole in the adipose tissue.

Myostatin (MSTN), a member of the TGF-β superfamily, is a negative regulator of skeletal muscle mass. We have previously shown that the cell survival/apoptosis pathway is a downstream target of MSTN loss-of-function in mice through the regulation of the expression or abundance of many survival and apoptotic factors. In this study, we used western-blot and quantitative PCR (qPCR) analyses to validate these novel downstream targets of MSTN in double-muscled (DM) cattle v. their controls including 260-day-old foetuses and adult cows from the INRA95 strain. MSTN loss-of-function in DM foetuses and DM cows resulted in a glycolytic shift of the muscles (e.g. upregulation of H-MyBP, PGM1 and SNTA1 and downregulation of H-FABP), activation of cell survival pathway through regulation of some components of the PI3K/Akt pathway (e.g. upregulation of DJ-1 and Gsk-3βser9/Gsk-3βtotal ratio and downregulation of PTEN) and upregulation of cell survival factors translationally controlled tumour protein (14-3-3E, Pink1). We also found a lower abundance of pro-apoptotic transcripts and/or proteins (Caspase-3, caspase-8, caspase-9, BID, ID2 and Daxx) and a higher expression of anti-apoptotic transcripts (Traf2 and Bcl2l2) in DM muscles. All together, these results are in favour of activation of the cell survival pathway and loss of apoptosis pathway within the muscles of DM animals. Alteration of both pathways may increase myonuclear or satellite cell survival, which is crucial for protein synthesis. This could contribute to muscle hypertrophy in DM foetuses and DM cows.

To investigate the effect of dietary allicin on health and growth performance of weanling piglets, at 21 days of age. Two hundred and twenty-five piglets were weaned and randomly allocated into five groups. Piglets in the control group were fed diets supplemented with antibiotics. Those in the treatment groups were fed diets without antibiotics, but supplemented with allicin product (25% pure allicin oil) in the proportion of 0.10 g/kg, 0.15 g/kg, 0.20 g/kg and 0.25 g/kg in the diet, respectively. During the 28 days of the experiment, average daily weight gain increased linearly (P < 0.0001) and quadratically (P = 0.0014) as the level of dietary allicin increased. The feed gain ratio decreased linearly (P < 0.0001) and quadratically (P < 0.0001). As the dietary allicin level increased, the incidence of diarrhoea in the treatment piglets, especially female piglets decreased linearly (P = 0.0003) and tended to decrease quadratically (P = 0.0716). The number of flies alighting on the surface of the faeces of the piglets at each counting time point decreased linearly (P < 0.0001), quadratically (P < 0.0001) and cubically (P < 0.0001) as the dietary allicin level increased. In conclusion, supplementation of the diet with allicin may improve growth performance, reduce the incidence of diarrhoea and possibly improve their local environmental conditions by reducing the attractiveness of faeces to flies.

Transport of farm animals gives rise to concern about their welfare. Specific attention has been given to the duration of animal transport, and maximum journey durations are used in legislation that seek to minimise any negative impact of transport on animal welfare. This paper reviews the relatively few scientific investigations into effects of transport duration on animal welfare in cattle, sheep, horses, pigs and poultry. From the available literature, we attempt to distinguish between aspects, which will impair welfare on journeys of any duration, such as those associated with loading, and those aspects that may be exacerbated by journey time. We identify four aspects of animal transport, which have increasing impact on welfare as transport duration increases. These relate to (i) the physiological and clinical state of the animal before transport; and – during transport – to (ii) feeding and watering; (iii) rest and (iv) thermal environment. It is thus not journey duration per se but these associated negative aspects that are the cause of compromised welfare. We suggest that with a few exceptions, transport of long duration is possible in terms of animal welfare provided that these four issues can be dealt with for the species and the age group of the animals that are transported.

Spontaneous ovulatory activity (SOA) in spring has been used to study the out-of-season breeding ability of Merinos d’Arles (MA) ewes. Within this breed, an association was found between more intense seasonality and genotype −/− at a MnlI restriction site (allele − for its absence v. + for its presence) in Exon II of the MT1 receptor gene. This study was designed to ascertain whether this association results in a direct effect of the MT1 genotype on the expression of seasonality in MA ewes. In the first year of the study, genotyping of 314 MA ewes at locus MnlI was carried out and resulted in frequencies of 43.0%, 44.9% and 12.1% for genotypes +/+, +/− and −/−, respectively. The SOA of these ewes was determined in early April of two consecutive years by assaying plasma progesterone concentrations in two blood samples taken 9 days apart. Groups of 30 ewes of each homozygous genotype (+/+ and −/−) were identified from this population and their SOA was followed by taking blood samples at regular intervals between January and mid-April of the second and third year of the study. In the second year, groups of ewes were managed together on rangelands, whereas in the third year each group was split into two subgroups given differential feed levels. The results clearly showed that genotype had no significant effect on SOA during the 2- to 3-month period preceding the introduction of rams for spring mating. In the second year of the study, in which the experimental procedure allowed a fair comparison of the fertility of ewes in spring mating, fertility was similar for both genotypes. The reciprocity of the association was not demonstrated and the MnlI polymorphic site could not be used as a genetic marker of selection for out-of-season breeding ability, at least not in the MA breed. The percentage of cycling ewes significantly decreased between January and April, and older ewes (5 or 6 years old depending on the year of the study) were more cyclic than younger ones (2 and 3 years old, respectively). The differential feeding level of ewes from early February did not significantly affect their SOA during the time period studied in the third year of the study.

Two experiments were conducted to ascertain the effects of feeding an all-concentrate diet to growing heifers on performance, ruminal fermentation, behaviour and welfare. In experiment 1, eight tethered rumen fistulated Holstein heifers (143 ± 8.7 kg, initial BW) were used to study the effects of treatment on intake, ruminal changes and behaviour. In experiment 2, 48 Friesian female calves (initial BW = 84.5 ± 1.37 kg) were used to study the effects of treatment on performance, behaviour and welfare in feedlot conditions. In both experiments, treatments consisted of concentrate with barley straw (BS) or without barley straw (NBS) and feed was offered at 0830 h on an ad libitum basis. Experiment 1 was performed in four 42-day periods, and sampling was carried out in the last week of each period. Ruminal samples were collected over 3 days at 0, 4, 8 and 12 h post-feeding to measure pH, and volatile fatty acids (VFA) and NH3-N concentrations. Maintenance behaviour was video-recorded for 24 h over three consecutive days of each experimental period and feed intake pattern was studied by means of feed bunks mounted on digital platform scales. There were no statistical differences in average daily gain (ADG), concentrate dry matter (DM) intake or CP intake. In contrast, NDF intake and ADF intake were greater in heifers fed BS than NBS. Average ruminal pH was lower, whereas total VFA was greater, in heifers fed NBS diet. There were no differences in NH3-N, and in d- and l-lactate concentrations. Time spent in ruminating was shorter, and stereotypies were more frequent in heifers fed diet NBS compared with those fed BS. In experiment 2, nine 28-day periods were established, in which DM intake and ADG were measured, blood and faecal samples were taken for haptoglobin and glucocorticoid metabolites determination, respectively, as welfare indicators, and behaviour was monitored by video recording. Concentrate intake was similar in both treatments, but total feed intake was greater in heifers fed BS diet. As there were no differences in ADG between treatments, gain efficiency was lower in those fed BS than those fed NBS. Blood haptoglobin and faecal glucocorticoids metabolites were not different between treatments. In these competitive conditions, rumination was also reduced and stereotypic behaviour increased by straw exclusion. In conclusion, performance was either not affected or improved by straw exclusion, but animal behaviour was affected, suggesting a negative effect on animal welfare.

This study was conducted to examine the influence of supplementation of sodium butyrate, sodium monensin or calcium propionate in a starter diet on the performance and selected plasma metabolites (plasma glucose, non-esterified fatty acids and β-hydroxybutyrate) of Holstein calves during pre- and post-weaning periods. Twenty-four newborn Holstein calves were housed in individual hutches until 10 weeks of life, receiving water free choice, and fed four liters of milk daily. Calves were blocked according to weight and date of birth, and allocated to one of the following treatments, according to the additive in the starter: (i) sodium butyrate (150 g/kg); (ii) sodium monensin (30 mg/kg); and (iii) calcium propionate (150 g/kg). During 10 weeks, calves received starter ad libitum, while coast cross hay (Cynodon dactylon (L.) pers.) was offered after weaning, which occurred at the 8th week of age. Weekly, calves were weighted and evaluated for body measurements. Blood samples were taken weekly after the fourth week of age, 2 hours after the morning feeding, for determination of plasma metabolites. No differences were observed among treatments for starter or hay intake, BW and daily gain of the animals. Mean concentrations of selected plasma metabolites were similar in calves fed a starter supplemented with sodium butyrate, sodium monensin and calcium propionate. There was significant reduction in the concentrations of plasma glucose as calves aged. The inclusion of sodium butyrate, calcium propionate or sodium monensin as additives in starter feeds resulted in equal animal performance, before and after weaning, suggesting that sodium monensin may be replaced by organic acid salts.

A trial was carried out over a 7-year period (1999 to 2005 calf crops) to compare indicators of seasonality in Angus cattle, which were part of a long-term genetic selection experiment. Divergent selection was applied for early (‘AGE−’) or late (‘AGE+’) age at puberty (AP) in heifers, and selection lines differed over the 7-year period by 62 days (15% of the mean). The primary measures of seasonality studied in 629 heifer progeny (59 sire groups) were serum concentration of prolactin (PRL), and winter and summer hair growth. Serial samples were obtained for PRL from 11 to 18 months of age, and data were analysed with adjustment for cortisol concentration. Using restricted maximum likelihood procedures with an animal model, heritability estimates were: AP, 0.26 ± 0.03; logePRL concentration, 0.23 ± 0.07; logecortisol concentration, 0.22 ± 0.07; hair weight, 0.21 ± 0.04; and hair length, 0.09 ± 0.05. Corresponding repeatability estimates for the last four traits were 0.49 ± 0.03, 0.38 ± 0.03, 0.21 ± 0.04, and 0.64 ± 0.02, respectively. The genetic correlation between AP and logePRL concentration was estimated at −0.29 ± 0.13 (P < 0.05). PRL concentration in the AGE− line after passing through puberty was 11 ± 5% lower than in the AGE+ line (P < 0.05). Line effects were not significant for hair weight or hair length. It was concluded that divergent selection for AP changed PRL concentration, which may partly reflect sensitivity to changing day length.

The goal of this study was to examine the ability of a commercially available feed additive (OmniGen-AF) to reduce mammary infections caused by a single strain of mastitic pathogens (Streptococcus uberis, Escherichia coli, Staphylococcus aureus and Klebsiella pneumoniae) and to examine the effects of the additive on markers of mammary immunity. Four experiments were completed using a murine model of bovine mastitis. Infection progression was examined using Sybr-green- and TaqMan-based quantitative PCR assays of 16S ribosomal DNA. Infection of the mammary gland with all pathogens caused rapid (24 to 48 h) appearance of pathogen DNA in mammary tissue. Provision of the feed additive for 2 weeks before infection significantly (P < 0.05) reduced the extent of pathogen DNA accumulation in models of S. uberis, E. coli and S. aureus infection. The additive was ineffective in reducing mammary infections caused by K. pneumoniae. We examined mechanisms of action of the additive through assessment of mammary concentrations of mammary myeloperoxidase (MPO), major histocompatibility complex 2 class II (MHC) and macrophage inflammatory protein-1α (MIP) messenger RNA (mRNA) concentrations and by examining serum complement C3 concentration. Infection of the mammary gland increased concentrations of MPO and MHC mRNAs (P < 0.05). Ability of the pathogen to elicit changes in mammary MPO and MHC gene expression was enhanced by the provision of the additive for 2 weeks before infection. These data imply that the additive increased the mammary inflammatory response and increased antigen presentation during a mammary infection. Value of the additive in preventing mastitis in cattle awaits additional studies using a bovine model and further evaluation of additional strains of the pathogens used in this study.

In recent years, broiler mortality during transport to the slaughterhouse has become a cause for concern because of animal welfare considerations and associated economic losses. A descriptive and analytical epidemiological study was carried out to estimate the extent of DoA in poultry broiler production in the main producing regions of France and to determine factors influencing the DoA rate. Data regarding animal characteristics and rearing, catching, transport and lairage conditions were collected on farm and at the slaughterhouse for 404 chicken broiler flocks processed during 2005. The average DoA rate was 0.18% (from 0% to 1.4%). Variables found to be associated (P < 0.05) with the DoA rate in a multivariable negative binomial model were flock cumulative mortality on farm, the catching system (mechanical being more at risk than manual), the density in crates (more space allowance being associated with less mortality) and climatic conditions (rain and wind being associated with more DoA). Mortality during transport is thus related to all production steps from the farm to the slaughterhouse. Efforts have therefore to be made by all professionals to contain mortality on farm and during catching and transportation.