Search

The aim of the current study was to investigate the effects of delayed feeding, and supplementation with sodium butyrate or glutamine in drinking water, on intestinal permeability (IP) in young broiler chickens. Newly-hatched male chickens (Ross 308) were allocated to four groups comprising Control, 24 h delayed fed (DF), DF supplemented with sodium butyrate (0.1%) in the drinking water and DF supplemented with glutamine (1%) in the drinking water. On days 2, 4 and 7, twelve birds per group were randomly selected, weighed and orally gavaged with fluorescein isothiocyanate dextran (FITC-d) at 2.2 mg / ml / chicken. Serum FITC-d concentration was analysed by spectrophotometry while serum diamine oxidase and d-lactic acid concentrations were analysed by microplate reader. FITC-d concentrations in the Control and DF groups were not statistically different on any day, suggesting that delayed feeding did not affect IP. Additionally, sodium butyrate increased IP compared to DF and Control on day 2 only (p

Summary Short-term fasting for 4.5 and 9 hr has been demonstrated to increase intestinal permeability (IP) in chickens. This study aimed to investigate the effects of 0, 4.5, 9 and 19.5 hr fasting on intestinal gene expression and villus-crypt architecture of enterocytes in jejunal and ileal samples. On day 38, Ross-308 male birds were fasted according to their group and then euthanised. Two separate intestinal sections (each 2 cm long, jejunum and ileum) were collected. One section was utilised for villus height and crypt depth measurements. The second section was snap-frozen in liquid nitrogen for quantitative polymerase chain reaction (qPCR) analysis of tight junction proteins (TJP) including claudin-1, claudin-3, occludin, zonula occludens (ZO-1, ZO-2), junctional adhesion molecules (JAM) and E-cadherin. Additionally genes involved in enterocyte protection including glucagon-like peptide (GLP-2), heat-shock protein (HSP-70), intestinal alkaline phosphatase (IAP), mammalian target of rapamycin (mTOR), toll-like receptors (TLR-4), mucin (MUC-2), cluster differentiation (CD-36) and fatty acid-binding protein (FABP-6) were also analysed. Normally distributed data were analysed using one-way analysis of variance ANOVA. Other data were analysed by non-parametric one-way ANOVA. Villus height and crypt depth were increased (p

Fasting of up to 24 hr has been shown to increase intestinal permeability (IP) in chickens. The aim of this study was to determine whether fasting duration of 4.5 and 9 hr increased IP and whether l-glutamine (a non-essential amino acid) supplementation before fasting provided some protection of barrier function as shown in other species. Ross 308 male broilers (n = 96) were fed either a control diet or the same diet supplemented with 1% glutamine from d0 to d38 post-hatch. On d37, the birds were assigned to single-bird metabolism cages and were fasted for either 0, 4.5, 9 or 19.5 hr. This study design was 2 × 4 factorial with two levels of glutamine and four levels of fasting. Birds in the 0-hr fasting group had free access to feed. All birds had ad libitum access to water. To measure IP on day 38, following their respective fasting periods, birds were administered two separate oral gavages of fluorescein isothiocyanate dextran (FITC-d) followed by lactulose, mannitol and rhamnose (LMR) sugars, 60 min apart. Whole blood was collected from the jugular vein 90 min post-LMR sugar gavage. FITC-d and L/M/R ratios were measured by spectrophotometry and high-performance ionic chromatography respectively. Lipopolysaccharide (LPS) endotoxins in plasma of the birds fed the control diet were also measured using chicken-specific LPS antibody ELISA. Serum FITC-d and plasma L/M and L/R ratios for 4.5, 9 and 19.5 hr were significantly (p .05) higher compared to the non-fasting group. However, IP was not different in the glutamine-supplemented group (p .05) compared to the control group. LPS concentrations measured by the ELISA were below the detectable range. We conclude that fasting periods of 4.5 and 9 hr increased IP compared to non-fasted birds and dietary glutamine supplementation did not ameliorate changes in IP.

Increased intestinal permeability (IP) can lead to compromised health. Limited in vivo IP research has been conducted in chickens. The objectives of the current study were to develop a model of increased IP utilizing lipopolysaccharide (LPS Escherichia coli O55:B5) and to evaluate IP changes using the lactulose, mannitol and rhamnose (LMR) sugar permeability test. In addition, fluorescein isothiocyanate dextran (FITC-d), d-lactate, zonula occludens (ZO-1) and diamine oxidase (DAO) permeability tests were employed. Male Ross chickens were reared until day 14 on the floor in an animal care facility and then transferred to individual cages in three separate experiments. In each of experiments 1 and 2, 36 chicks were randomly allocated to receive either saline (control) or LPS (n=18/group). Lactulose, mannitol and rhamnose sugar concentration in blood was measured at 0, 30, 60, 90, 120 and 180 min in experiment 1, at 60, 90 and 120 min in experiment 2 and at 90 min in experiment 3 (n=16/group). Lipopolysaccharide was injected intraperitoneally at doses of 0.5, 1 and 1 mg/kg BW in experiments 1, 2 and 3, respectively, on days 16, 18 and 20, whereas control received sterile saline. On day 21, only birds in experiments 1 and 2 were fasted for 19.5 h. Chicks were orally gavaged with the LMR sugars (0.25 gL, 0.05 gM, 0.05 gR/bird) followed by blood collection (from the brachial vein) as per time point for each experiment. Only in experiment 3, were birds given an additional oral gavage of FITC-d (2.2 mg/ml per bird) 60 min after the first gavage. Plasma d-lactate, ZO-1 and DAO concentrations were also determined by ELISA in experiment 3 (n=10). Administration of LPS did not affect IP as measured by the LMR sugar test compared with control. This was also confirmed by FITC-d and DAO levels in experiment 3 (P>0.05). The plasma levels of d-lactate were decreased (P

Increased intestinal permeability (IP) can lead to compromised health in chickens. As there is limited literature on in vivo biomarkers to assess increased IP in chickens, the objective of this study was to identify a reliable biomarker of IP using DSS ingestion and fasting models. Male Ross chickens (n = 48) were reared until day 14 on the floor pen in an animal care facility, randomized into the following groups: control, DSS and fasting (each with n = 16), and then placed in metabolism cages. DSS was administered in drinking water at 0.75% from days 16 to 21, while controls and fasted groups received water. All birds had free access to feed and water except the birds in the fasting group that were denied feed for 19.5 h on day 20. On day 21, all chickens were given two separate oral gavages comprising fluorescein isothiocyanate dextran (FITC-d, 2.2 mg in 1 ml/bird) at time zero and lactulose, mannitol and rhamnose (LMR) sugars (0.25 g L, 0.05 g M and 0.05 g R in 2 ml/bird) at 60 min. Whole blood was collected from the brachial vein in a syringe 90 min post-LMR sugar gavage. Serum FITC-d and plasma LMR sugar concentrations were measured by spectrophotometry and high-performance ion chromatography respectively. Plasma concentrations of intestinal fatty acid binding protein, diamine oxidase, tight junction protein (TJP), d-lactate and faecal α-antitrypsin inhibitor concentration were also analysed by ELISA. FITC-d increased significantly (p 0.05) after fasting compared with control. L/M and L/R ratios for fasting and L/M ratio for DSS increased compared with control chickens (p 0.05). TJP in plasma was significantly increased due to fasting but not DSS treatment, compared with controls. Other tests did not indicate changes in IP (p 0.05). We concluded that FITC-d and LMR sugar tests can be used in chickens to assess changes in IP.

Benefits of long-chain (≥C20) omega-3 oils (LC omega-3 oils) for reduction of the risk of a range of disorders are well documented. The benefits result from eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA); optimal intake levels of these bioactive fatty acids for maintenance of normal health and prevention of diseases have been developed and adopted by national and international health agencies and science bodies. These developments have led to increased consumer demand for LC omega-3 oils and, coupled with increasing global population, will impact on future sustainable supply of fish. Seafood supply from aquaculture has risen over the past decades and it relies on harvest of wild catch fisheries also for its fish oil needs. Alternate sources of LC omega-3 oils are being pursued, including genetically modified soybean rich in shorter-chain stearidonic acid (SDA, 18:4ω3). However, neither oils from traditional oilseeds such as linseed, nor the SDA soybean oil have shown efficient conversion to DHA. A recent breakthrough has seen the demonstration of a land plant-based oil enriched in DHA, and with omega-6 PUFA levels close to that occurring in marine sources of EPA and DHA. We review alternative sources of DHA supply with emphasis on the need for land plant oils containing EPA and DHA.

An observational study on range enrichment was conducted on three commercial fixed-range, free-range layer farms comprising four flocks in South Australia (flock sizes ranged from 3000 to 11700 hens). Two strategies were compared; a ‘standard’ Control treatment, typical of the type of range used in the commercial industry and a highly ‘enriched’ treatment. Both treatments were implemented on the same range with no subdivisional fences. The highly enriched side of the range incorporated shade shelters, alongside a continuum of additional enrichment structures (e.g. dust baths, peck objects and hay bales). Range treatments were investigated to determine the effects on motivating hens to use the range more effectively, and their potential to lead to a decrease in abnormal behaviours, such as injurious feather pecking and cannibalism. Additionally, two farms with high levels of tree coverage were also observed. Farms were visited monthly for 6 months. At each visit several measures were recorded live: the numbers of hens out on the range, location of hens on the range and plumage score of birds outdoors and indoors. Enrichment structure utilisation on the range was measured via video recordings and continuous counts of the number of hen visits to enrichment structures within 1 h. It was found that more hens used the ‘enriched’ side of the range, in comparison with the ‘standard’ Control range treatment (P ≤ 0.01). Overhead cover provided by constructed shelters and dust bathing pits were instrumental in enticing birds out onto the range (306 ± 27 s.e.m. and 366 ± 24 s.e.m., average number hen visits). Hay bales were also highly utilised (116 ± 14 s.e.m., average number hen visits), even though the hen numbers attracted to the hay bales were not as high as shelters and dust baths. It was also observed on one property that natural cover provided by trees attracted the greatest number of hens (1652 ± 358 s.e.m., average number of hen visits). Prevailing weather conditions and the age of the flock strongly influenced the number of hens utilising the range outdoors. Furthermore, hens outside on the range had better plumage scores with lower feather loss and decreased areas of bare skin compared with birds scored in the shed.

The skeletal muscle is the largest organ in the body. It plays a particularly pivotal role in glucose homeostasis, as it can account for up to 40% of the body and for up to 80%–90% of insulin-stimulated glucose disposal. Hence, insulin resistance (IR) in skeletal muscle has been a focus of much research and review. The fact that skeletal muscle IR precedes β-cell dysfunction makes it an ideal target for countering the diabetes epidemic. It is generally accepted that the accumulation of lipids in the skeletal muscle, due to dietary lipid oversupply, is closely linked with IR. Our understanding of this link between intramyocellular lipids (IMCL) and glycemic control has changed over the years. Initially, skeletal muscle IR was related to total IMCL. The inconsistencies in this explanation led to the discovery that particular lipid intermediates are more important than total IMCL. The two most commonly cited lipid intermediates for causing skeletal muscle IR are ceramides and diacylglycerol (DAG) in IMCL. Still, not all cases of IR and dysfunction in glycemic control have shown an increase in either or both of these lipids. In this review, we will summarise the latest research results that, using the lipidomics approach, have elucidated DAG and ceramide species that are involved in skeletal muscle IR in animal models and human subjects.

Stearidonic acid (SDA; C18:4n-3) has been suggested as an alternative to fish oil (FO) for delivering health benefits of C ≥ 20 long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA). Echium oil (EO) represents a non-genetically-modified source of SDA available commercially. This study compared EO and FO in relation to alterations in plasma and tissue fatty acids, and for their ability to afford protection against ischemia-induced cardiac arrhythmia and ventricular fibrillation (VF). Rats were fed (12 weeks) diets supplemented with either EO or FO at three dose levels (1, 3 and 5% w/w; n = 18 per group). EO failed to influence C22:6n-3 (DHA) but increased C22:5n-3 (DPA) in tissues dose-dependently, especially in heart tissue. Conversely, DHA in hearts of FO rats showed dose-related elevation; 14.8%–24.1% of total fatty acids. Kidney showed resistance for incorporation of LC n-3 PUFA. Overall, FO provided greater cardioprotection than EO. At the highest dose level, FO rats displayed lower (p < 0.05) episodes of VF% (29% vs. 73%) and duration (22.7 ± 12.0 vs. 75.8 ± 17.1 s) than the EO group but at 3% EO was comparable to FO. We conclude that there is no endogenous conversion of SDA to DHA, and that DPA may be associated with limited cardiac benefit.

Echium oil is a naturally rich source of stearidonic acid (SDA; C18:4 n −3), an n −3 polyunsaturated fatty acid ( n −3 PUFA) which is a precursor to the long chain (LC) n −3 polyunsaturated fatty acids (LC n −3 PUFA) eicosapentaenoic (EPA, C20:5 n −3) and docosahexaenoic (DHA, C22:6 n −3). The latter are LC n −3 PUFA for which there is accumulating evidence for positive cardiovascular health claims in human consumers. To determine the extent to which SDA supplementation can enrich milk fat with EPA and DHA, we supplemented 5 dairy cows on irrigated pasture with Echium oil for 10 d. The oil supplement was ruminally protected against biohydrogenation by using a protein–aldehyde matrix. Milk samples were collected during supplementation and 1, 2 and 30 d after supplementation ceased. Echium oil supplementation had no effect on levels of milk crude protein, fat, lactose and solids-not-fat. Average daily milk yield gradually declined as the period of supplementation progressed, and returned to pre-supplementation period levels after withdrawal of the supplement. The proportions of α-linolenic acid (ALA, 18:3 n −3), SDA, EPA and total n −3 PUFA in milk fat increased in response to supplementation. The initial (Day 1) and final (Day 10) concentrations (in mg/l) of ALA, SDA, EPA and DPA in whole milk were 463 ± 29.2 versus 877 ± 63.1, 38 ± 8.6 versus 144 ± 12.4, 13 ± 6.2 versus 76 ± 9.0 and 45 ± 4.5 versus 65 ± 4.3, respectively. ALA, SDA, EPA and total n −3 PUFA concentrations increased linearly with increasing days of supplementation, while increases in DPA concentrations were curvilinear with a 3–4 d delay in their rise. DHA was not detected in milk fat. In terms of fatty acid yield/cup (i.e., 250 ml) of whole milk, enrichment of milk with EPA amounted to an increase from around 3.1–13.9 mg. As there was no change in DHA content, the long-chain n −3 PUFA content based on EPA alone was less than half of the cut-off point for omega-3 “source” claim (30 mg EPA + DHA per human serving) for foods in Australia. However, the total n −3 PUFA content of milk increased from 559 ± 41.0 to 1162 ± 82.4 mg/l. Data suggest that this oil containing SDA enriched milk with EPA, but not DHA. Dose response and large scale studies are needed to determine the optimal dietary inclusion rate and the commercial feasibility of SDA-containing oils as a means of increasing n −3 fatty acids in dairy cow milk.

Vegetable oils containing stearidonic acid (SDA, 18 : 4n-3) are considered better precursors of long-chain n-3 PUFA (LC n-3 PUFA) than those with only α-linolenic acid (ALA, 18 : 3n-3). The present study re-examined this premise using treatments where added ALA from linseed oil was matched with ALA plus SDA from echium oil. Lambs (n 6) were abomasally infused with saline (control (C), 25 ml), echium oil low (EL, 25 ml), echium oil high (EH, 50 ml), linseed oil low (LL, 25 ml) or linseed oil high (LH, 50 ml) for 4 weeks. The basal ration used was identical across all treatments. EPA (20 : 5n-3) in meat increased from 6·5 mg in the C lambs to 16·8, 17·7, 13·5 and 11·7 (sem 0·86) mg/100 g muscle in the EL, EH, LL and LH lambs, respectively. For muscle DPA (docosapentaenoic acid; 22 : 5n-3), the corresponding values were 14·3, 22·2, 18·6 18·2 and 19·4 (sem 0·57) mg/100 g muscle. The DHA (22 : 6n-3) content of meat was 5·8 mg/100 g in the C lambs and ranged from 4·53 to 5·46 (sem 0·27) mg/100 g muscle in the oil-infused groups. Total n-3 PUFA content of meat (including ALA and SDA) increased from 39 mg to 119, 129, 121 and 150 (sem 12·3) mg/100 g muscle. We conclude that both oil types were effective in enhancing the EPA and DPA, but not DHA, content of meat. Furthermore, we conclude that, when balanced for precursor n-3 fatty acid supply, differences between linseed oil and echium oil in enriching meat with LC n-3 PUFA were of little, if any, nutritional significance.

Summary Increasing recognition of the health benefits of omega-3 long-chain (FC20) polyunsaturated fatty acids (omega-3 LC-PUFA or LC omega-3 oils) continues. But new sources are needed, with recent developments with novel land plants showing promise. The value of existing and future sources LC omega-3 oils occurs through aquaculture, livestock and other feeding. There is also a need toenhance the stability of oils containing LC omega-3 oils. Challenges include increasing DHA levels in land plants, increasing oxidative stability in food products and product labeling. Consumers have difficulty recognizing and differentiating long-chain and shorter-chain (SC, C18) omega-3 PUFA, both of which are referred to as “omega-3” fatty acids.

A feeding experiment was conducted to determine if the duration of supplementation of lambs with protected linseed oil (PLO) affected the apparent conversion of alpha linolenic acid (ALA) into the longer chain n-3 polyunsaturated fatty acids PUFA (n-3 PUFA): eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Forty-eight 4-month-old Merino lambs with mean initial live weights of 29.5 ± 0.27 kg were divided into four groups of 12 and randomly assigned to 0PLO, 3PLO, 6PLO or 9PLO treatments corresponding to 0, 3, 6 and 9 weeks of PLO supplementation, respectively. At slaughter, all groups had similar live weight (37–40 kg), hot carcass weight (15–16 kg) and ultimate pH (5.76–5.85). The intramuscular fat content was lower ( P Longissimus dorsi muscle were greatest in the first three weeks. PLO increased ( P L. dorsi ; changes in EPA were not significant. The total n-3 (mg/100 g muscle) content was higher in the supplemented group ( P P P >0.05) between treatments. The PLO supplement was effective in significantly enriching lamb meat with n-3 PUFA in three weeks, but longer periods were required to increase the levels of the longer chain PUFAs that are required for “source claim” and product differentiation.

α-Linolenic acid (ALA; 18 : 3n-3) and stearidonic acid (SDA; 18 : 4n-3) are on the biosynthetic pathway of EPA (20 : 5n-3) and DHA (22 : 6n-3). Then-3 fatty acid in rapeseed oil is ALA while Echium oil contains both ALA and SDA. To determine the comparative efficacy of ALA- and SDA-rich oils in enriching broiler meat withn-3 PUFA, we offered diets supplemented with rapeseed oil (rapeseed group) or Echium oil (Echium group) for 35 d to two groups of chicks (age 21 d). There were no differences in carcass weight (2·20 (sem0·06)v.2·23 (sem0·05) kg), boned, skinless thigh muscle (494 (sem20·5)v.507 (sem16·7) g), boned, skinless breast muscle (553 (sem13·4)v.546 (sem11·6) g) or organ weights (heart, liver and gizzard) between the two groups. The total intramuscular fat (IMF) percentage of thigh (8·0 (sem0·64)v.8·1 (sem0·62) %) and breast muscles (2·3 (sem0·24)v.2·0 (sem0·19) %) were also similar between the groups. In contrast, the concentrations of most of the individualn-3 fatty acids (ALA, SDA, EPA and docosapentaenoic acid) were all higher in the Echium than the rapeseed group (P n-3 yields/100 g serve thigh muscle were 265 and 676 mg for the rapeseed and Echium groups, respectively (P P n-3 fatty acids, except DHA, in broiler meat.

The present study was conducted to determine the pattern of incorporation of dietary EPA and docosahexaenoic acid (DHA) into milk, and to evaluate consequent changes in milk fat composition and sensory characteristics. Fourteen multiparous cows in early lactation were divided into two groups and were offered supplements for 10 d. While individual stalls after each morning milking, one group was offered a mixture of rumen-protected tuna oil (RPTO)–soyabean supplement (2 kg; 30:70, w/w; +RPTO) and the second group was offered the basal ration without RPTO (−RPTO). Both groups grazed together on a spring pasture after supplementation. Feeding supplemental RPTO increased the concentrations of EPA and DHA in milk fat from undetectable levels in −RPTO cows to 6·9 and 10·1 g/kg milk fat respectively. Total n-3 PUFA concentration in milk fat was increased three- to fourfold by tuna-oil supplementation (8·4 to 32·0 g/kg milk fat). There were no significant effects on milk production (35·4 v. 33·9 l/d), milk protein (28·2 v. 30·1 g/kg) or milk fat (36·2 v. 40·4 g/kg for −RPTO and +RPTO respectively). The concentration of total saturated fatty acids in milk fat was significantly reduced (568 v. 520 g/kg total fatty acids) and there was a 17 % reduction in the atherosclerotic index of milk after tuna-oil supplementation. Untrained consumer panellists (n 61) rated milk from both groups of cows similarly for taste and smell. We conclude that it is possible to enrich milk with n-3 PUFA without deleterious effects on yield, milk composition or sensory characteristics.

A study was conducted to determine whether protected tuna oil can be used to enrich sheep’s milk with eicosapentaenoic acid (EPA, 20:5) and docosahexaenoic acid (DHA, 22:6) without affecting milk yield or composition. Sixteen sheep in late lactation were selected from a dairy herd and assigned into two groups: Control (C) and protected tuna oil (PTO)-supplemented group. The two groups were run in adjacent paddocks where both had ad libitum access to oaten hay. Both were group-fed lupins (500 g per animal per day) in a trough after morning (06:00 h) and afternoon (15:00 h) milking. At morning milking the PTO group were offered a mixture of chaff (160 g) and molasses-coated (80:20, w/w), protected tuna oil supplement (150 g). At each milking, the control group were offered 50–100 g of a mixture of oaten chaff (0.70) and lupins (0.30) for contentment during milking. Supplement feeding lasted 10 days and milk samples were collected from Day 0 (pre-feeding) to 6 days post-feeding period. Tuna oil supplementation did not affect daily milk yield (722±81 ml versus 716±80 ml), fat (74±8.3 g/kg versus 77±0.8.6 g/kg) or protein percent (54±6.0 g/kg versus 56±6.3 g/kg; C versus PTO, respectively). No apparent residual effect on milk yield or composition was detected 6 days post-feeding period. The levels of EPA and DHA in milk fat from the PTO group increased linearly from Day 2 (0.7±0.7 g/kg and 1.7±0.6 g/kg) up to Day 6 (3.2±0.8 g/kg and 170±1.8 g/kg) and tended to plateau thereafter (Day 10 values: 4.7±0.5 g/kg and 19±0.9 g/kg, respectively). Six days after the supplement-feeding period, the milk from the PTO group was still significantly enriched with n −3 PUFA (EPA: 2.3±0.9 g/kg; DHA: 6.5±0.9 g/kg). No EPA or DHA was detected in milk samples from the non-supplemented group. The apparent transfer of dietary EPA and DHA to milk was 0.21±0.02 for EPA and 0.18±0.03 for DHA (computed using milk samples from Day 10). A cup (250 ml) of such n −3 PUFA-enriched milk will provide two-thirds (437 mg, 0.67) of the recommended daily intake of EPA plus DHA (650 mg) for adults. This study provides an approach that enables enrichment of milk with health-enhancing fatty acids without deleterious consequences on milk yield or composition.

The effects of Eimeria (EM) and Clostridium perfringens (CP) challenges on the mRNA levels of genes involved in mucin (Muc) synthesis (Muc2, Muc5ac, Muc13, and trefoil family factor-2 [TFF2]), inflammation (tumor necrosis factor alpha [TNF-alpha] and interleukin-18 [IL-18]), and metabolic processes (cluster of differentiation [CD]36) in the jejunum of broilers were investigated. Two parallel experiments involving 1) EM challenge and 2) EM and CP challenges were conducted. The first experiment was a 2 X 2 study with 12 birds per treatment (N = 48) involving fishmeal substitution (25%) in the diet (FM) and EM challenge. The treatments were: Control (FM-, EM-), Fishmeal (FM+, EM-), EM challenge (FM-, EM+), and fishmeal substitution and EM challenge (FM+, EM+). The second experiment was a 2 X 2 X 2 experiment with six birds per treatment (N = 48) involving fishmeal (FM-, FM+), Eimeria (EM-, EM+), and C perfringens (CP-, CP+). In both arms of the study, male broilers were given a starter diet for the whole period of 16 days, except those assigned to FM+, where 25% of the starter ration was replaced with fishmeal from days 8 to 14. EM inoculation was performed on day 9 and CP inoculation on days 14 and 15. The EM challenge birds were euthanatized for sampling on day 13; postmortem examination and sampling for the Eimeria plus C perfringens challenge arm of the study were on day 16. In the Eimeria challenge arm of the study, fishmeal supplementation significantly suppressed the mRNA levels of TNF-alpha, TFF2, and IL-18 pre-CP inoculation but simultaneously increased the levels of Muc13 and CD36 mRNAs. Birds challenged with Eimeria exhibited increased mRNA levels of Muc13, Muc5ac, TNF-alpha, and IL-18. In the Eimeria and C. perfringens challenge arm, birds exposed to EM challenge exhibited significantly lower mRNA levels of Muc2 and CD36. The mRNA levels of CD36 were also significantly suppressed by CP challenge. Our results showed that the transcription of mucin synthesis genes in the jejunum of broilers is modulated by fishmeal inclusion in the diet. Furthermore, we show for the first time suppression of CD36 mRNA levels in the intestine of broilers challenged with Eimeria or C. perfringens.

Nichols et al. (Lipids Health Dis13:2, 2014) raised concern about the higher n-6 concentration in fish oil used in our recent study which is different from typical commercial fish oils (Ramprasath et al. Lipids Health Dis12:178, 2013). The aim of our study was to compare the effect of consumption of similar amount of n-3 PUFA from krill and fish oil with placebo on plasma and RBC fatty acids. As the concentration of n-3 PUFA in the fish oil utilised was higher than that in krill oil, we deemed it important to keep consistent the concentration of n-3 PUFA and volumes to be administered to participants between krill versus fish oils. As such, the fish oil used in the study was diluted with corn oil. Although the n-6 PUFA concentration in fish oil was higher compared to traditionally used fish oil, consumption of the fish oil used in our study actually reduced the total n-6 PUFA in plasma and RBC to a similar extent as did krill oil. Overall, our conclusion was that the increases in plasma and RBC concentrations of EPA and DHA along with improvement in the omega-3 index observed with consumption of krill oil compared with fish oil are due to differences in absorption and bioavailability based on the structural difference of the two oils rather than their n-6 PUFA content.

A study was conducted to determine the transfer of eicosapentaenoic acid (EPA, 20:5) and docosahexaenoic acid (DHA, 22:6) from fish oil into goats’ milk. Goats were sequentially offered three diets: control (C) pellets (lucerne hay-oat grain: 60/40 w/w), C plus tuna oil protected against ruminal biohydrogenation (PTO pellets), and C plus unprotected tuna oil (UTO pellets). In supplemented diets, tuna oil constituted 3% of total dry matter (DM), and each supplement was fed for 7 days, with 12 days allowed between the two fish oil feeding periods to minimise carry-over effects. Dry matter intake, milk yield, protein and fat yield were reduced by feeding UTO, but not PTO, pellets. Goats produced ω-3 enriched milk (0.3–0.5% EPA and 1.01–1.12% DHA) when fed either supplement. The rate of transfer of dietary EPA and DHA to milk ranged from 3.5 to 7.6%. Significant transfer of EPA and DHA from tuna oil into goat milk, without deleterious effects on intake or milk yield is possible, provided that the oil supplement is substantially protected against ruminal biohydrogenation.

In vitro incubations were used to assess the hydrogenation of conjugated linoleic acid (CLA) isomers 9-cis 11-trans and 10-trans 12-cis present in synthetically produced CLA-60. About 80‐ 90% of the unprotected CLA was hydrogenated when incubated at 388C for 24 h anaerobically with sheep rumen fluid, the main end product of hydrogenation being trans-octadecaenoic acid (C18:1). Encapsulation of the CLA in a matrix of protein provided a protection of about 70% with a 30% hydrogenation of the CLA isomers, resulting in no significant change in the trans-C18:1 but an increase in the level of stearic acid (C18:0). Feeding sheep with unprotected CLA or protected CLA increased the proportion of isomers 9-cis 11-trans and 10-trans 12-cis in abomasal digesta. The concentration of the CLA isomers leaving the abomasum and available for absorption at the small intestine was about 3.5‐4% higher for the protected CLA, confirming protection imparted by encapsulation. Feeding lactating goats with protected CLA increased the proportion of isomers 9-cis 11-trans and 10-trans 12-cis in milk fat. The total CLA levels were enhanced by about 10-fold above the control levels present in milk fat with an efficiency of transfer into milk fat of 36‐41% and 21‐30%, respectively, for the two isomers. # 2000 Published by Elsevier Science B.V.

Intestinal health is influenced by a complex set of variables involving the intestinal microbiota, mucosal immunity, digestion and absorption of nutrients, intestinal permeability (IP) and intestinal integrity. An increase in IP increases bacterial or toxin translocation, activates the immune system and affects health. IP in chickens is reviewed in three sections. First, intestinal structure and permeability are discussed briefly. Second, the use of lipopolysaccharide (LPS) as a tool to increase IP is discussed in detail. LPS, a glycolipid found in the outer coat of mostly Gram-negative bacteria, has been reported to increase IP in rats, mice and pigs. Although LPS has been used in chickens for inducing systemic inflammation, information regarding LPS effects on IP is limited. This review proposes that LPS could be used as a means to increase IP in chickens. The final section focuses on potential biomarkers to measure IP, proposing that the sugar-recovery method may be optimal for application in chickens.

This chapter summarizes the agronomic description, health benefits, and toxicity associated with the use of echium seeds for human health. Echium seed oil has a combination of specific n-3 and n-6 PUFAs that are involved in inflammatory processes in the body. In addition to the well-recognized benefits against CVD, conditions and diseases where the evidences of n-3 PUFAs are considered to be greater are asthma, inflammatory bowel disease, and rheumatoid arthritis. The oil has two main distinguishing features from other vegetable oils: (1) it is naturally rich in SDA, and (2) its n-6 fatty acid content includes γ-linolenic acid (GLA), which is thought to lead to production of anti-inflammatory eicosanoids. Animal experiments and direct human supplementation studies show that echium seed oil can bring about beneficial changes in biomarkers of chronic diseases, such as lowering triacylglycerol (TAG) in plasma and tissue. Anti-inflammatory relief can be considered the basis of both the herbal medicine and modern use of echium seed oil as an essential oil and nutritional supplement. However, echium plants produce alkaloids as a chemical defense mechanism. The specific echium alkaloids are called pyrrolizidine alkaloids (PAs). PAs are hepatotoxic and cause liver damage.

Using performance from progeny born in 2007 and 2008 generated by the Information Nucleus program of the Cooperative Research Centre for Sheep Industry Innovation, preliminary estimates of heritability were obtained for a range of novel carcass and meat attributes of lamb relevant to consumers, including carcass characteristics, meat quality and nutritional value of lamb. Phenotypic and genetic correlations of live animal traits with carcass composition and meat quality traits were also estimated. The data were from progeny located at eight sites, sired by 183 rams from Merino, maternal and terminal meat breeds and were representative of the Merino, Border Leicester × Merino, Terminal × Merino and Terminal × Border Leicester-Merino production types of the Australian sheep industry. Data were available from 7176 lambs for weaning weight, 6771 lambs for ultrasound scanning and 4110 lambs for slaughter traits. For the novel meat quality traits, generally moderate to high heritability estimates were obtained for meat quality measures of shear force (0.27 aged 1 day, 0.38 aged 5 days), intramuscular fat (0.39), retail meat colour (range of 0.09 to 0.44) and myoglobin content (0.22). The nutritional value traits of omega-3 fatty acids and iron and zinc contents tended to have low to moderate heritabilities (0.11–0.37), although these were based on fewer records. Fresh meat colour traits were of low to moderate heritability (0.06–0.21) whereas measures of meat pH were of low heritability (~0.10). For the carcass traits, estimates of heritability were moderate to high for the various measures of carcass fat (0.18–0.50), muscle weight (0.22–0.35), meat yield (0.24–0.35), carcass muscle dimensions (0.25–0.34) and bone weight (0.27). Results indicate that for most lamb carcass and meat quality traits there is sufficient genetic variation for selection to alter successfully these characteristics. Additionally, most genetic correlations of live animal assessments of bodyweight, muscle and subcutaneous fat with the carcass and meat quality traits were favourable. Appropriate definition of breeding objectives and design of selection indexes should be able to account for the small unfavourable relationships that exist and achieve the desired outcomes from breeding programs.

Thirty 7-month-old crossbred lambs (Poll Dorset × Border Leicester × Merino) finished over 5 weeks on either low quality pasture or grain-with-hay on a farm in southern Victoria were assessed for carcass parameters, muscle fat composition and retail colour stability. Lambs on the grain diet had a mix of barley grain (80%) and lentils (20%) at 800 g/head.day (air-dry basis ~ad libitum) with cape weed (Arctotheca calendula) hay available at all times. Lambs under grazing had predominantly rye grass (Lolium perenne) and barley grass (Hordeum leporinum) available ad libitum. Carcass weight tended to be higher (P = 0.14) in grain-fed lambs than in grass-fed lambs, but fatness indicated by GR (total muscle + fat tissue thickness at 11 cm from midline) did not differ between feeding systems. Fatty acid composition was determined in the loin from the forequarter (M. longissimus thoracis) and lumbar (M. longissimus lumborum) regions and from the leg region (M. semimembranosus). This showed that grain-finished lamb had higher muscle fat (P < 0.001) and omega-6 fatty acid (P < 0.001) content. Alpha-linolenic acid, eicosapentaenoic acid (EPA) or total omega-3 fat did not differ (P > 0.05) between feeding groups. Saturated fatty acids were greater (P < 0.01) in both loin sampling sites than the leg. The levels of EPA, docosahexaenoic acid and docosapentaenoic acid were lower (P < 0.01) in the forequarter (9%) or lumbar (11%) sites than the leg sampling site. The distribution pattern of fatty acids across the three sampling sites did not differ between feed types. Retail colour stability determined over 4 days of display (only performed in muscle from the lumbar site), evaluated by the redness (HunterLab a*-value) and metmyoglobin formation (reflectance ratio at 630 : 580-nm wavelengths) was superior for grass-fed lamb compared with short-term grain-finished lamb. The results demonstrate that the health claimable omega-3 fat mainly EPA or total omega-3 fat content in lamb was not altered by short-term grain finishing compared with lamb finished under pasture grazing conditions.

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are the n-3 polyunsaturated fatty acids (n-3 PUFA) for which there is ample evidence of human health benefits, and these are also the fatty acids for which there are cut-off points for ‘source’ and ‘good source’ claims. Two consecutive experiments were conducted to determine the effect of finishing systems on the n-3 PUFA content of lamb meat in Western Australia. In experiment I, a 4-week feeding experiment was conducted using 48 Poll Dorset × Merino lambs. The lambs were divided into two lots of 24 (12 males and 12 females) and randomly assigned to either concentrate (C1) finishing on commercial lamb finishing pellets or pasture (P) finishing on kikuyu (Pennisetum clandestinum) pasture. In experiment II, 28 lambs were divided into two groups of 14 lambs (seven males and seven females) and assigned to finishing either on concentrate pellets (C2) or concentrate pellets plus linseed (C2-L). This second experiment was conducted indoors for 10 weeks. The initial liveweight (mean ± s.e.) of the lambs was 43 ± 0.6 and 32.5 ± 0.9 kg for experiments I and II, respectively. At the end of experiment II, three chops each were sampled from the leg, loin, forequarter and neck region of each carcass. The final liveweight (42 ± 0.8 v. 50 ± 1.2 kg), hot carcass weight (19 ± 0.5 v. 24 ± 0.7 kg) and GR depth (5.6 ± 0.6 v. 12.8 ± 0.6 mm) were lower (P < 0.05) for P than C1 lambs. In contrast, C2 and C2-L lambs had similar final liveweight (44 ± 0.7 v. 45 ± 0.9 kg), hot carcass weight (19 ± 0.3 v. 20 ± 0.5 kg) and GR depth (13 ± 1.3 v. 14 ± 1.2 mm). In experiment I, the total n-3 PUFA yields for C1 and P lambs in the M. longissimus lumborum were 67 ± 2.5 and 78 ± 3.2 mg per 100 g muscle, respectively. The EPA plus DHA yields were 17 and 21 mg per 100 g muscle, respectively. The sum of the long-chain (≥C20) n-3 PUFA EPA, docosapentaenoic acid and DHA for C1 and P lambs were 30 and 37 mg per 100 g, respectively. Sex had no effect on any of the n-3 fatty acids. In experiment II, the total n-3 PUFA yields for C2 lambs were 61, 54, 60 and 104 mg per 100 g for leg, loin, forequarter and neck chops, respectively. The respective values for C2-L lambs were 153, 138, 139 and 178 mg per 100 g muscle. The claimable EPA plus DHA yields for C2 lambs were 13, 10, 12 and 15 mg per 100 g of trimmed leg, loin, forequarter and neck chops, respectively. The respective values for C2-L lambs were around 2-fold higher at 27, 21, 25 and 23 mg per 100 g raw meat. All the samples from pasture-finished and linseed-supplemented groups met the 30 mg cut-off point for ‘source’ claim in Australia when the computation was based on 100 g cooked lamb serve (140 g raw). We conclude that pasture-finished lambs have more n-3 PUFA per serve than their counterparts finished indoors on commercial pellets. Further, supplementing indoor-finished lambs with linseed provided equivalent n-3 PUFA per serve to finishing lambs on pasture. Supplementation with an omega-3 source improved omega-3 per serve across the whole carcass irrespective of sex.

To re-evaluate the incorporation of n-3 fatty acids into depot fats and muscle a group of lambs were fed indoors a concentrate ration supplemented (3% DM) with much lower levels than used previously of rumen-protected tuna oil for 42 days. A second group of lambs were fed diets supplemented with tallow (3% DM) to make the diets iso-caloric. There was no difference in final liveweight, average daily gain, hot carcass yield, or dry matter intake (DMI) between lambs fed with tallow and tuna oil-supplemented diets. Both eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) levels in muscle tissue samples from tuna oil-fed lambs were thrice those in tallow-fed lambs (1.81% v. 0.61% for EPA; 1.51 v. 0.44% total fatty acids for DHA). There were also significant incorporations of EPA and DHA into omental and perirenal fat. The level of linolenic acid in both muscle and adipose tissue of tuna oil fed lambs was double that of tallow-fed lambs. Feeding protected tuna oil significantly enhanced the n-3 fatty acid content of lamb meat.

Digestibility is a very useful index of the energy content of ruminant feeds, but cheaper and quicker laboratory methods are required as an alternative to the ultimate measure of in vivo digestibility using animals. These methods involve either prediction of digestibility from chemical composition or in vitro and in situ simulation of the digestion process. This review presents a range of chemical and in vitro techniques for predicting digestibility, together with an assessment of their advantages and limitations, particularly the degree to which they account for the sources of variation in in vivo digestibility in ruminants. In situ digestion of feed samples in the actual rumen environment is probably the most accurate of the non in vivo procedures, but is not suitable for routine application. Thein vitro gas production technique offers no advantages in prediction of total tract digestibility, but is useful for screening cereal grains for rate of starch hydrolysis in the rumen. The preferred procedure for routine laboratory prediction of digestibility is the pepsin-cellulase technique, provided amylase is included or high temperature digestion is used for samples high in starch content. Prediction of digestibility from chemical composition is not recommended. The optical technique of near infrared reflectance spectroscopy can be calibrated against any of the methods outlined in this review, and is unsurpassed in terms of speed and repeatability. Direct NIR prediction of in vivo digestibility is also possible, but is limited by the lack of adequate numbers of feed samples with known in vivo values. Future work should be aimed at filling this gap and also improving the accuracy of laboratory methods for predicting the digestibility of low quality feeds.