Most athletic horses are fed a high-starch diet despite the risk of health problems. Replacing starch concentrate with high-energy forage would alleviate these health problems, but could result in a shift in major substrates for muscle energy supply from glucose to short-chain fatty acids (SCFA) due to more hindgut fermentation of fibre. Dietary fat inclusion has previously been shown to promote aerobic energy supply during exercise, but the contribution of SCFA to exercise metabolism has received little attention. This study compared metabolic response with exercise and lactate threshold (VLa4) in horses fed a forage-only diet (F) and a more traditional high-starch, low-energy forage diet (forage–concentrate diet - FC). The hypothesis was that diet F would increase plasma acetate concentration and increase VLa4 compared with diet FC. Six Standardbred geldings in race training were used in a 29-day change-over experiment. Plasma acetate, non-esterified fatty acids (NEFA), lactate, glucose and insulin concentrations and venous pH were measured in samples collected before, during and after a treadmill exercise test (ET, day 25) and muscle glycogen concentrations before and after ET. Plasma acetate concentration was higher before and after exercise in horses on diet F compared with diet FC, and there was a tendency (P = 0.09) for increased VLa4 on diet F. Venous pH and plasma glucose concentrations during exercise were higher in horses on diet F than diet FC, as was plasma NEFA on the day after ET. Plasma insulin and muscle glycogen concentrations were lower for diet F, but glycogen utilisation was similar for the two diets. The results show that a high-energy, forage-only diet alters the metabolic response to exercise and, with the exception of lowered glycogen stores, appears to have positive rather than negative effects on performance traits.

The present study aimed to evaluate some cytochrome P450 metabolic enzyme activities in hepatic microsomes prepared from entire male pigs (uncastrated pigs), surgically castrated pigs and pigs immunized against gonadotropin-releasing hormone (immunocastrated pigs). The activities of the following enzymes were measured: ethoxyresorufin O-deethylase (EROD, CYP1A1/1A2), methoxyresorufin O-deethylase (MROD, CYP1A2), pentoxyresorufin O-depentylase (PROD, CYP2B), coumarin hydroxylase (COH, CYP2A) and p-nitrophenol hydroxylase (PNPH, CYP2A/2E1). The total cytochrome P450 contents were not affected by either surgical or immunocastration. Hepatic microsomal activities for EROD, PROD, COH and PNPH were lower in entire male pigs compared with surgically castrated and immunocastrated pigs (P < 0.05). Surgically and immunocastrated male pigs were similar with respect to EROD, MROD, PROD and COH activities (P > 0.05), whereas surgically castrated pigs exhibited lower PNPH activity compared with immunocastrated pigs (P = 0.029). The effect of different concentrations of testicular steroids – testosterone, 17β-estradiol, free estrone and androstenone – on enzyme activities was evaluated by in vitro microsomal study. Testosterone at the concentration of 8 pmol/ml inhibited EROD activities and estradiol-17β at the concentration of 1.8 pmol/ml inhibited PROD activities in hepatic microsomes from surgically castrated pigs. The highest concentration of androstenone (7520 pmol/ml) inhibited COH activities, whereas a 42-fold lower concentration of androstenone (180 pmol/ml) stimulated COH activities in surgically castrated pigs. Both free estrone (3.5 pmol/ml) and androstenone (55 pmol/ml) inhibited EROD activities in microsomes from entire male pigs. Stimulation of COH activities by the highest dose of free estrone (18 pmol/ml) was recorded in microsomes from entire male pigs. However, these effects of steroids were not concentration-dependent and the maximum extent did not exceed ±15% variation compared with the controls. There was no inhibition of PNPH activities in the hepatic microsomes from either entire or castrated pigs. In conclusion, we showed that EROD, PROD, COH and PNPH activities were lower in entire male pigs compared with those in surgically and immunocastrated pigs. Direct inhibition by the testicular steroids – testosterone, 17β-estradiol, free estrone and androstenone – was not the primary cause of the reduced enzyme activities.

In beef cattle, feeding behaviour and activity are associated with feed efficiency and methane (CH4) emissions. This study aimed to understand the underlying traits responsible for the contribution of cattle behaviour to individual differences in feed efficiency, performance and CH4 emissions. A total of 84 steers (530±114 kg BW) of two different breeds (crossbreed Charolais and Luing) were used. The experiment was a 2×2×3 factorial design with breed, basal diets (concentrate v. mixed) and dietary treatments (no additive, calcium nitrate or rapeseed cake) as the main factors. The individual dry matter intake (DMI; kg) was recorded daily and the BW was measured weekly over a 56-day period. Ultrasound fat depth was measured on day 56. Based on the previous data, the indexes average daily gain, food conversion and residual feed intake (RFI) were calculated. The frequency of meals, the duration per visit and the time spent feeding per day were taken as feeding behaviour measures. Daily activity was measured using the number of steps, the number of standing bouts and the time standing per day. Agonistic interactions (including the number of contacts, aggressive interactions, and displacements per day) between steers at the feeders were assessed as indicators of dominance. Temperament was assessed using the crush score test (which measures restlessness when restrained) and the flight speed on release from restraint. Statistical analysis was performed using multivariate regression models. Steers that spent more time eating showed better feed efficiency (P=0.039), which can be due to greater secretion of saliva. Feeding time was longer with the mixed diet (P<0.001), Luings (P=0.009) and dominant steers (P=0.032). Higher activity (more steps) in the pen was associated with poorer RFI, possibly because of higher energy expenditure for muscle activity. Frequent meals contributed to a reduction in CH4 emissions per kg DMI. The meal frequency was higher with a mixed diet (P<0.001) and increased in more temperamental (P=0.003) and dominant (P=0.017) steers. In addition, feed intake was lower (P=0.032) in more temperamental steers. This study reveals that efficiency increases with a longer feeding time and CH4 emissions decrease with more frequent meals. As dominant steers eat more frequently and for longer, a reduction in competition at the feeder would improve both feed efficiency and CH4 emissions. Feed efficiency can also be improved through a reduction in activity. Selection for calmer cattle would reduce activity and increase feed intake, which may improve feed efficiency and promote growth, respectively.

When modelling the effect of a changing nutrient supply to growing animals, it is important to distinguish the individual response curve of an animal from the change in this response that may occur during growth. A data analysis model is proposed where, for an individual animal, the relation between protein deposition (PD) and metabolizable energy (ME) intake above maintenance (MEp) is curvilinear, so that PD intersects the origin and reaches its maximum at the maximum protein deposition rate (PDmax). An increase of MEp beyond that required to attain PDmax would not change PD. The MEp not used for protein synthesis can be used for lipid deposition (LD). The relation between PD and LD on the one hand and ME on the other hand can then be described as a function of the maintenance energy requirement (MEm), PDmax, the level of ME required to attain PDmax (F; as a multiple of MEm) and the energetic efficiencies of PD (kp) and LD (kf). Of these statistics, only kp and kf were assumed to be independent of body weight (BW), age or genotype. Variation in PDmax was described as a Gompertz function (of age) whereas variation in F was assumed a linear function of BW. Maintenance energy requirement was expressed as a power function of BW. To evaluate the model, 145 nitrogen and energy (indirect calorimetry) balances were obtained from three types of pigs (Large White castrated males (cLW) and Piétrain × Large White castrated males (cPP× ) and males (bPP×)) ranging in BW between 45 and 100 kg and housed under thermoneutral conditions. Animals were allotted to one of four energy levels ranging from 0·70 to 1·00 of ad libitum intake. The MEm was not different between genotypes (849 kJ/kg BW0·60) whereas the kp and kf were 0·56 and 0·75, respectively. For castrated animals on ad libitum intake, PDmax started limiting PD at approximately 130 days of age (78 and 86 kg BW for cLW and cPP×, respectively). Before this age and for bPP×, PD was limited by MEp. In bPP×, the difference between PD and PDmax was small (less than proportionately 0·05). The F did not change with BW for bPP× (2·85 × MEm) whereas for the other genotypes, it decreased linearly from 4·47 at 45 kg to 2·00 at 100 kg of BW. Due to its nature, the model allows estimation of PDmax even when energy is restricting PD.

Red clover and fish oil (FO) are known to alter ruminal lipid biohydrogenation leading to an increase in the polyunsaturated fatty acid (PUFA) and conjugated linoleic acid (CLA) content of ruminant-derived foods, respectively. The potential to exploit these beneficial effects were examined using eight Hereford × Friesian steers fitted with rumen and duodenal cannulae. Treatments consisted of grass silage or red clover silage fed at 90% of ad libitum intake and FO supplementation at 0, 10, 20 or 30 g/kg diet dry matter (DM). The experiment was conducted with two animals per FO level and treatments formed extra-period Latin squares. Flows of fatty acids at the duodenum were assessed using ytterbium acetate and chromium ethylene diamine tetra-acetic acid as indigestible markers. Intakes of DM were higher (P < 0.001) for red clover silage than grass silage (5.98 v. 5.09 kg/day). There was a linear interaction effect (P = 0.004) to FO with a reduction in DM intake in steers fed red clover silage supplemented with 30 g FO/kg diet DM. Apparent ruminal biohydrogenation of C18:2n-6 and C18:3n-3 were lower (P < 0.001) for red clover silage than grass silage (0.83 and 0.79 v. 0.87 and 0.87, respectively), whilst FO increased the extent of biohydrogenation on both diets. Ruminal biohydrogenation of C20:5n-3 and C22:6n-3 was extensive on both silage diets, averaging 0.94 and 0.97, respectively. Inclusion of FO in the diet enhanced the flow of total CLA leaving the rumen with an average across silages of 0.22, 0.31, 0.41 and 0.44 g/day for 0, 10, 20 or 30 g FO/kg, respectively, with a linear interaction effect between the two silages (P = 0.03). FO also showed a dose-dependent increase in the flow of trans-C18:1 intermediates at the duodenum from 4.6 to 15.0 g/day on grass silage and from 9.4 to 22.5 g/day for red clover silage. Concentrations of trans-C18:1 with double bonds from Δ4–16 in duodenal digesta were all elevated in response to FO in both diets, with trans-11 being the predominant isomer. FO inhibited the complete biohydrogenation of dietary PUFA on both diets, whilst red clover increased the flow of C18:2n-6 and C18:3n-3 compared with grass silage. In conclusion, supplementing red clover silage-based diets with FO represents a novel nutritional strategy for enhancing the concentrations of beneficial fatty acids in ruminant milk and meat.

Although veal production is a highly standardized system, there still remains considerable variability in productivity between units. This variability might be due to the farmers working on these units, through differences in stockmanship, work attitudes or behaviour, which in turn may affect animals’ fear responses, productivity and health. A survey was conducted on 50 commercial farms affiliated to the same veal company. All units had calves housed in individual crates, a similar number of crates, and the same diets and management advice. Data were collected on: building and general farm characteristics, farmers’ backgrounds and their attitudes towards their work and calves, farmers’ behaviour with the calves, calves’ reactivity to people, and disease level of the calves. Productivity results (growth rates, food efficiency and mortality) were used to classify veal units as ‘high producing’ (no. = 24) v. ‘moderate producing’ (no. = 26). Calves were less reactive to people in units where the farmer behaved sympathetically and where there were several stockpersons working. The disease level was lower in units where the farmer had a positive attitude towards the sensitivity of the calves to contact and towards the importance of cleaning. Productivity of the veal unit was associated with the health of the calves but not with their reactivity to people.

It is suggested that the farmer can have an influence on the success of the veal unit mainly through his/her ability to control the health of the calves and that a positive attitude towards animals and towards work (specifically cleaning actions) can improve the accuracy of surveillance and care of the animals. Moreover, through his/her behaviour with the calves and his/her ability to control their health, the farmer can play an important rôle in assuring calves’ welfare.

Fatty acids are important modulators of inflammatory responses, in particular, n-3 and n-6 essential fatty acids and CLA have received particular attention for their ability to modulate inflammation. The objectives of this study were to compare the effects of CLA and essential fatty acids on the expression of pro and anti- inflammatory cytokines and their protective efficacy against inflammatory status in mammary gland by an in vitro model based on bovine mammary epithelial cells (BME-UV1). Bovine mammary epithelial cells were treated with complete medium containing either 50 µM of cis-9, trans-11 CLA (c9,t11 CLA) or trans-10, cis-12 CLA (t10,c12 CLA) or (α)-linolenic acid (aLnA) or (γ)-linolenic acid (gLnA) or linoleic acid (LA). After 48 h by fatty acids administration the cells were treated for 3 h with 20 µM of lipopolysaccharide (LPS) to induce inflammatory stimulus. Reactive oxygen species (ROS) production after treatments was assessed to verify and to compare the potential protection of different fatty acids against LPS-induced oxidative stress. The messenger RNA abundance of bovine pro and anti-inflammatory cytokines (tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6) and interleukine-10 (IL-10)) and peroxisome proliferator receptor-α/γ (PPARγ/α) were determined in BME-UV1 by real-time PCR. The results showed that cells treated with fatty acids and LPS increased ROS production compared with control cells. Among treatments, cells treated with c9,t11 CLA and t10,c12 CLA isomers revealed significant lower levels of ROS production compared with other fatty acids. All fatty acids reduced the gene expression of pro- and anti-inflammatory cytokines. Among fatty acids, t10,c12 CLA, LA and gLnA showed an homogeneous reduction of the three pro-inflammatory cytokines and this may correspond to more balanced and efficient physiological activity and may trigger a better protective effect. The PPARγ gene expression was significantly greater in cells treated with t10,c12 CLA, aLnA and LA, whereas the PPARα gene expression levels were significantly lower in cells treated with all different fatty acids, compared with the control. These results suggest that fatty acids inhibited the transcription of pro-inflammatory cytokines by the upregulation of PPARγ expression.

Two experiments were conducted with weaned, suckled calves to investigate the effect of feeding level during the post-weaning winter on their subsequent performance when continuously grazed on pasture maintained at two sward heights. Low, medium and high levels of winter feeding resulted in winter live-weight gains of 0·31, 0·58 and 0·79 (s.e. 0·027) kg/day (P < 0·001) during the 152-day winter in experiment 1 and 0·44, 0·69 and 0·84 (s.e. 0·029) kg/day (P < 0·001) for 189 days in experiment 2. During summer (93 days in experiment 1 and 87 days in experiment 2) there was a significant effect of winter food level on performance when live-weight gains were 1·10, 1·02, 0·87 and 1·35, 1·23 and 1·19 (s.e. 0·060) kg/day for the low, medium and high winter food levels on the short and tall swards respectively in experiment 1 (P < 0·01) and 0·86, 0·66, 0·51 and 1·26, 1·18 and 0·91 (s.e. 0090) kg/day in experiment 2 (P < 0·001). The cattle showing compensatory growth had higher herbage intakes and it is postulated that this occurred because of a negative association between body fat and herbage intake. Sward height had a large positive effect on herbage intake and live-weight gain and it is concluded that for maximum intake on ryegrass swards, herbage height should be at least 8 cm. Lower levels of winter live-weight gain delayed the time to slaughter, but allowed cattle to achieve heavier carcass weights at a fixed level of fatness.

It is concluded that there is no single optimum winter food level for weaned, suckled calves but that the choice will depend upon several factors, including availability of winter and summer food resources, the length of the winter feeding period, the desired date of slaughter and type of carcass to be produced.

The difficulties and costs of measuring individual feed intake in dairy cattle are the primary factors limiting the genetic study of feed intake and utilisation, and hence the potential of their subsequent industry-wide applications. However, indirect selection based on heritable, easily measurable, and genetically correlated traits, such as conformation traits, may be an alternative approach to improve feed efficiency. The aim of this study was to estimate genetic and phenotypic correlations among feed intake, production, and feed efficiency traits (particularly residual feed intake; RFI) with routinely recorded conformation traits. A total of 496 repeated records from 260 Holstein dairy cows in different lactations (260, 159 and 77 from first, second and third lactation, respectively) were considered in this study. Individual daily feed intake and monthly BW and body condition scores of these animals were recorded from 5 to 305 days in milk within each lactation from June 2007 to July 2013. Milk yield and composition data of all animals within each lactation were retrieved, and the first lactation conformation traits for primiparous animals were extracted from databases. Individual RFI over 301 days was estimated using linear regression of total 301 days actual energy intake on a total of 301 days estimated traits of metabolic BW, milk production energy requirement, and empty BW change. Pair-wise bivariate animal models were used to estimate genetic and phenotypic parameters among the studied traits. Estimated heritabilities of total intake and production traits ranged from 0.27±0.07 for lactation actual energy intake to 0.45±0.08 for average body condition score over 301 days of the lactation period. RFI showed a moderate heritability estimate (0.20±0.03) and non-significant phenotypic and genetic correlations with lactation 3.5 % fat-corrected milk and average BW over lactation. Among the conformation traits, dairy strength, stature, rear attachment width, chest width and pin width had significant (P<0.05) moderate to strong genetic correlations with RFI. Combinations of these conformation traits could be used as RFI indicators in the dairy genetic improvement programmes to increase the accuracy of the genetic evaluation of feed intake and utilisation included in the index.

The objective of this study was to investigate the effects of strain of Holstein-Friesian cow, pasture-based feeding system (FS) and their interaction on milk production, dry matter (DM) intake and energy balance over 3 years consecutively. The three strains were: high milk production North American (HP), high fertility and survival (durability) North American (HD) and New Zealand (NZ). The FS were: a high grass allowance (HG FS), a high concentrate (HC FS) and a high stocking rate (HS FS). A separate farmlet existed for each FS and a total of 99, 117 and 117 animals were used in year 1, year 2 and year 3, respectively, divided equally between strains and FS. Individual animal intakes were estimated three times each year at pasture; in May (P1), in July (P2) and October (P3), corresponding on average to day 102, 177 and 240 of lactation, respectively. The HP cows achieved the highest milk yield, the NZ the lowest, while the HD was intermediate; the HP achieved the highest solid corrected milk yield with no difference between the NZ and HD strains. The grass DM intake of the HP strain was highest ( P<0·001) in all feeding systems. There was a significant strain×FS interaction for yield of milk, fat and protein, grass DM and total DM intake. The milk production response to the HC FS in P1 and P2 was significantly greater for both the HP and HD strains than for the NZ strain, while in P3 the response was highest for the HP, lowest for the NZ and intermediate for the HD. The reduction in pasture DM intake per kg of concentrate was greatest for the NZ strain, lowest for the HP and intermediate for the HD strain. The NZ strain also had the highest grass DM intake per kg live weight. The existence of strain×FS interactions for production and DM intake indicate that greater knowledge of both genotype and feeding environment is required to predict animal performance.

The objective of this study was to determine the effects of dietary crude protein (CP) level on odour emission, odour intensity, hedonic tone, and ammonia emission from pig manure and on manure composition (pH, total nitrogen, ammonium, volatile fatty acids, indolic, phenolic and sulphur-containing compounds). An experiment was conducted with growing pigs (n = 18) in a randomised complete-block design with three treatments in six blocks. Treatment groups were 12%, 15% and 18% CP diets. Barley was exchanged for soya-bean meal. Crystalline amino acids (AA) were included in the 12% CP diet up to the level of pigs' requirement; the same amount of AA was added to the 15% and 18% CP diets. Pigs with an initial body weight (BW) of 36.5 ± 3.4 kg (mean ± s.d.) were individually penned in partly slatted floor pens and offered a daily feed allowance of 2.8 × maintenance requirement for net energy (NE: 293 kJ/kg BW0.75). Feed was mixed with water, 1/2.5 (w/w). Faeces and urine of each pig were accumulated together in a separate manure pit under the slatted floor. After an adaptation period of 2 weeks, the manure pits were cleaned and manure was collected. In the 5th week of the collection period, air samples for odour and ammonia analyses, and manure samples were collected directly from each manure pit. Air samples were analysed for odour concentration and for hedonic value and intensity above odour detection threshold. Manure samples were analysed for volatile fatty acids, and indolic, phenolic and sulphurous compounds, ammonium and total nitrogen concentrations. Reducing dietary CP from 18% to 12% lowered odour emission ( P < 0.05) and ammonia emission ( P = 0.01) from pig manure by 80% and 53%, respectively. Reduced dietary CP decreased total nitrogen, methyl sulphide, carbon disulphide, ethanethiol, phenol, 4-ethyl phenol, indole and 3-methyl indole concentrations in the manure ( P < 0.05). Volatile fatty acids and cresols concentrations in the manure of pigs fed different dietary CP levels were similar. A reduction of dietary CP and at the same time providing essential AA is an option to reduce odour emission as well as ammonia emission from pig manure.

This study was conducted to evaluate the effect of a 12-h light, 12-h dark (12L : 12D) photoperiod of green light during day 1 to day 18 of incubation time, on embryo growth, hormone concentration and the hatch process. In the test group, monochromatic light was provided by a total of 204 green light-emitting diodes (522 nm) mounted in a frame which was placed above the top tray of eggs to give even spread of illumination. No light–dark cycle was used in the control group. Four batches of eggs (n=300/group per batch) from fertile Ross 308 broiler breeders were used in this experiment. The beak length and crown–rump length of embryos incubated under green light were significantly longer than that of control embryos at day 10 and day 12, respectively (P<0.01). Furthermore, green light-exposed embryos had a longer third toe length compared with control embryos at day 10, day 14 and day 17 (P=0.02). At group level (n=4 batches), light stimulation had no effect on chick weight and quality at take-off, the initiation of hatch and hatch window. However, the individual hatching time of the light exposure focal chicks (n=33) was 3.4 h earlier (P=0.49) than the control focal chicks (n=36) probably due to the change in melatonin rhythm of the light group. The results of this study indicate that green light accelerates embryo development and alters hatch-related hormones (thyroid and corticosterone), which may result in earlier hatching.

Piétrain (P), Large White (LW) and Belgian Landrace stress negative (BN) boars were slaughtered at 50, 70, 90 or 110 kg live weight to investigate breed differences and the effect of slaughter weight on boar taint prevalence. Boar taint was quantified by four different methodologies: sensory evaluation of neckfat heated with a hot iron in the slaughterhouse, sensory evaluation of meat by consumer panels, sensory evaluation of fat and meat by expert panels and laboratory analysis of indole, skatole and androstenone in backfat. Skatole levels in backfat were significantly higher for LW and BN than for P boars. The androstenone levels and the hot iron method revealed a significant interaction between breed and slaughter weight. On the other hand, experts detected an effect of weight on the androstenone odour perception, which was significantly higher in fat from boars slaughtered at 90 kg compared with 50 kg, and significantly higher in meat from boars slaughtered at 110 kg compared with 50 kg. Consumers did not detect differences in the sensory characteristics among breeds or slaughter weight. These results indicate opportunities to minimise the risk of boar taint in entire male pigs by carefully selecting a combination of breed and slaughter weight. Along with the optimal slaughter weight, the effectiveness of reducing boar taint by lowering slaughter weight appeared to be breed dependent.

Exploring the composition and structure of the faecal microbial community improves the understanding of the role of the gut microbiota in the gastrointestinal function and the egg-laying performance of hens. Therefore, detection of hen–microbial interactions can explore a new breeding marker for the selection of egg production due to the important role of the gut microbiome in the host’s metabolism and health. Recently, the gut microbiota has been recognised as a regulator of host performance, which has led to investigations of the productive effects of changes in the faecal microbiome in various animals. In the present study, a metagenomics analysis was applied to characterise the composition and structural diversity of faecal microbial communities under two selections of egg-laying performance, high (H, n = 30) and low (L, n = 30), using 16S rRNA-based metagenomic association analysis. The most abundant bacterial compositions were estimated based on the operational classification units among samples and between the groups from metagenomic data sets. The results indicated that Firmicutes phylum has higher significant (P < 0.01) in the H group than in the L group. In addition, higher relative abundance phyla of Bacteroides and Fusobacteria were estimated in the H group than the L group, contrasting the phyla of Actinobacteria, Cyanobacteria and Proteobacteria were more relative abundance in the L group. The families (Lactobacillus, Bifidobacterium, Acinetobacter, Flavobacteriaceae, Lachnoclostridum and Rhodococcus) were more abundant in the H group based on the comparison between the H and L groups. Meanwhile, three types of phyla (Proteobacteria, Actinobacteria and Cyanobacteria) and six families (Acinetobacter, Avibacterium, Clostridium, Corynebacterium, Helicobacter and Peptoclostridium) were more abundant in the L group (P < 0.01). Overall, the selection of genotypes has enriched a relationship between the gut microbiota and the egg-laying performance. These findings suggest that the faecal microbiomes of chickens with high egg-laying performance have more diverse activities than those of chickens with low egg-laying performance, which may be related to the metabolism and health of the host and egg production variation.

A 2 × 2 factorial experiment was carried out to evaluate the effect of herbage or concentrate feeding system and tannin addition to diet on skatole and indole in ruminal fluid and adipose tissue and meat sensory properties. Twenty-eight male lambs aged 45 days were randomly assigned to one of two feeding systems (vetch green herbage or concentrates, n = 14) and within feeding system to one supplement (quebracho tannins added to the diet or none). Animals were kept in singular pens and slaughtered at the age of 105 days. Indole (P < 0.05) and skatole (P < 0.01) concentrations in ruminal fluid were higher in lambs fed herbage compared to those given concentrates. Skatole in ruminal fluid tended to be present at lower concentrations in animals that received the tannin supplementation (P = 0.07). Indole was also higher in the caudal fat of animals fed green vetch compared to those fed concentrate (P = 0.04). Skatole concentration was lower in the fat of lambs fed concentrates compared to those given herbage (P = 0.05) and was lower in the fat of animals supplemented with tannins compared to the animals not supplemented (P = 0.01). Sheep meat odour was lower in meat from animals supplemented with tannins compared to those not supplemented (P < 0.01). It is concluded that tannins are more effective in reducing skatole formation in ruminants when they are associated with concentrate diets than green herbages.

Probiotics such as lactic acid bacteria directly influence the host’s health and have beneficial effects such as decreasing the number of enteric pathogens, regulating intestinal immune responses and preventing diseases. Among domestic animals, probiotics have been expected to be an alternative to antibiotics added in the diet; and fermented liquid diet (FLD) containing probiotics has great potential as a diet for reducing the use of antibiotics. In this study, we evaluated the immunomodulatory effects of FLD, prepared using Lactobacillus plantarum LQ80 (LQ80), on the immune response of weaning pigs. Ten weaning piglets were divided into two groups and were fed the FLD (n = 5) or a non-fermented liquid diet (NFLD) (n = 5) for 28 days. At the end of the experiment, the total immunoglobulin M (IgM) and immunoglobulin G (IgG) levels in the sera of the FLD-fed piglets were significantly higher than those of the NFLD-fed piglets (P < 0.05). In contrast, the total immunoglobulin A (IgA) levels in the feces and saliva were not significantly affected by FLD feeding. However, the mean fecal IgA levels of FLD-fed piglets at day 28 were higher than those at 14 and 21 days (P < 0.05). Blood cells from the FLD-fed piglets showed a low level of interferon-γ secretion and mitogen-induced proliferation compared to that of the NFLD-fed piglets. Furthermore, the levels of interluekin-8 and tumor necrosis factor-α, which are proinflammatory cytokines, in the blood cells of the FLD-fed piglets were lower than those of the NFLD-fed piglets (P < 0.05). In conclusion, the FLD used in this study could alter the immune responses of weaning piglets by stimulation of the systemic or mucosal antibody response, without unnecessary inflammatory reactions. This indicates, that the FLD feed prepared with the use of LQ80 may be a candidate feed, with regard to enhancing immune responses and preventing diseases in weaning piglets.

It is known that supplementing dairy cow diets with full-fat oilseeds can be used as a strategy to mitigate methane emissions, through their action on rumen fermentation. However, direct comparisons of the effect of different oil sources are very few, as are studies implementing supplementation levels that reflect what is commonly fed on commercial farms. The objective was to investigate the effect of feeding different forms of supplemental plant oils on both methane emissions and milk fatty acid (FA) profile. Four multiparous, Holstein-Friesian cows in mid-lactation were randomly allocated to one of four treatment diets in a 4×4 Latin square design with 28-day periods. Diets were fed as a total mixed ration with a 50 : 50 forage : concentrate ratio (dry matter (DM) basis) with the forage consisting of 75 : 25 maize silage : grass silage (DM). Dietary treatments were a control diet containing no supplemental fat, and three treatment diets containing extruded linseed (EL), calcium salts of palm and linseed oil (CPLO) or milled rapeseed (MR) formulated to provide each cow with an estimated 500 g additional oil/day (22 g oil/kg diet DM). Dry matter intake (DMI), milk yield, milk composition and methane production were measured at the end of each experimental period when cows were housed in respiration chambers for 4 days. There was no effect of treatment diet on DMI or milk protein or lactose concentration, but oilseed-based supplements increased milk yield compared with the control diet and milk fat concentration relative to control was reduced by 4 g/kg by supplemental EL. Feeding CPLO reduced methane production, and both linseed-based supplements decreased methane yield (by 1.8 l/kg DMI) and intensity (by 2.7 l/kg milk yield) compared with the control diet, but feeding MR had no effect on methane emission. All the fat supplements decreased milk total saturated fatty acid (SFA) concentration compared with the control, and SFA were replaced with mainly cis-9 18:1 but also trans FA (and in the case of EL and CPLO there were increases in polyunsaturated FA concentration). Supplementing dairy cow diets with these oilseed-based preparations affected milk FA profile and increased milk yield. However, only the linseed-based supplements reduced methane production, yield or intensity, whereas feeding MR had no effect.

Following parturition, contamination of the uterine lumen by bacteria is ubiquitous, and uterine health is impaired in cattle because infection persists in 10% to 15% of animals as endometritis. Endometritis causes infertility for the duration of infection, and subfertility persists even after apparent successful resolution of the disease. Escherichia coli is the pathogenic bacterium most frequently isolated from the post partum uterus, and is associated with increased concentrations of peripheral plasma acute phase proteins and fetid vaginal mucus. The presence of E. coli is also associated with slower growth of the first post partum dominant follicle and perturbed oestradiol secretion. Furthermore, in animals that ovulate the first dominant follicle, the corpus luteum is smaller and secretes less progesterone. The endotoxin lipopolysaccharide (LPS), which is released from E.coli, can pass from the uterine lumen to the peripheral circulation and LPS concentrations are increased in cows with uterine infection. Infusion of E. coli LPS into the uterine lumen suppresses the pre-ovulatory luteinising hormone surge and disrupts ovulation in heifers. In vitro, endometrial explants produce prostaglandins in response to LPS. Addition of LPS or E. coli to stromal or epithelial cells increases cyclooxygenase-2 mRNA expression, and stimulates the production of prostaglandin E2 and prostaglandin F2α . Furthermore, uterine and ovarian cells express mRNA of the molecules required for recognition of LPS, Toll-like receptor-4 and CD14. In summary, E. coli is a common cause of infertility involving the perturbation of the hypothalamus, pituitary and ovary in dairy cows.

The aim of this study was to determine the effects of supplementing unprotected dietary unsaturated fatty acids (UFAs) from different plant oils on gene expression in the mammary gland of grazing dairy cows. A total of 28 Holstein–Friesian dairy cows in mid-lactation were blocked according to parity, days in milk, milk yield and fat percentage. The cows were then randomly assigned to four UFA sources based on rapeseed, soybean, linseed or a mixture of the three oils for 23 days, after which, all 28 cows were switched to a control diet for an additional 28 days. On the last day of both periods, mammary gland biopsies were taken to study genome-wide differences in gene expression on Affymetrix GeneChip® Bovine Genome Arrays (no. 900493) by ServiceXS (Leiden, The Netherlands). Supplementation with UFAs resulted in increased milk yield but decreased milk fat and protein percentages. Furthermore, the proportion of de novo fatty acids (FAs) in the milk was reduced, whereas that of long-chain FAs increased. Applying a statistical cut-off of false discovery rate of q-values <0.05 together with an absolute fold change of 1.3, a total of 972 genes were found to be significantly affected through UFA supplementation, indicating that large transcriptional adaptations occurred in the mammary gland when grazing dairy cows were supplemented with unprotected dietary UFA. Gene sets related to cell development and remodeling, apoptosis, nutrient metabolic process, as well as immune system response were predominantly downregulated during UFA supplementation. Such molecular knowledge on the physiology of the mammary gland might provide the basis for further functional research on dairy cows.

Animals destined for meat production are usually exposed to many stressful conditions during production and particularly during preslaughter operations. Handling animals on farm, loading into and unloading from vehicles, transportation, passing through livestock markets, fasting, lairage and stunning can all affect their welfare. How badly welfare can be affected will depend on both the intrinsic factors of the specific type of animal involved and the extrinsic factors of the environment where those animals live or are being handled, including the animal handlers. In South America (SA), it has been part of a strategy for improving animal welfare (AW) to address not only ethical aspects, but to emphasize the close relationship existing between handling ruminants preslaughter and the quantity and quality of the meat they produce. This has resulted not only in improvements in AW, but has also brought economic rewards to producers which in turn can lead to higher incomes for them and hence better human welfare. For producers with a high number of animals, considering AW during production and preslaughter operations can determine the possibility of exporting and/or getting better prices for their products. At smallfarmer level, particularly in some less developed countries, where human welfare is impaired, using this strategy together with education has also been relevant. It is important that education and training in AW are done not only considering global knowledge, but also including specific geographical and climatic characteristics of each country and the cultural, religious and socio-economical characteristics of its people; therefore, research within the context of each country or region becomes relevant. The aim of this review was to show the results of research dealing with AW of ruminant livestock in Chile and some other SA countries. Some of the main problems encountered are related to lack of proper infrastructure to handle animals; long distance transport with high stocking densities in the larger countries; long fasting times due to animals passing through livestock markets and dealers; bad handling of animals by untrained personnel in these and other premises; and finally the lack of knowledge and skills by operators in charge of stunning procedures. Interventions at these stages have considered training animal handlers and transporters by showing them the consequences of bad handling with audiovisual material prepared on site. Research results have helped to improve AW and support the development of new legislation or to make changes in the existent legislation related to AW.