Efficacy of a parainfluenza virus 5 (PIV5)-based H7N9 vaccine in mice and guinea pigs: antibody titer towards HA was not a good indicator for protection.

H7N9 has caused fatal infections in humans. A safe and effective vaccine is the best way to prevent large-scale outbreaks in the human population. Parainfluenza virus 5 (PIV5), an avirulent paramyxovirus, is a promising vaccine vector. In this work, we generated a recombinant PIV5 expressing the HA gene of H7N9 (PIV5-H7) and tested its efficacy against infection with influenza virus A/Anhui/1/2013 (H7N9) in mice and guinea pigs. PIV5-H7 protected the mice against lethal H7N9 challenge. Interestingly, the protection did not require antibody since PIV5-H7 protected JhD mice that do not produce antibody against lethal H7N9 challenge. Furthermore, transfer of anti-H7 serum did not protect mice against H7N9 challenge. PIV5-H7 generated high HAI titers in guinea pigs, however it did not protect against H7N9 infection or transmission. Intriguingly, immunization of guinea pigs with PIV5-H7 and PIV5 expressing NP of influenza A virus H5N1 (PIV5-NP) conferred protection against H7N9 infection and transmission. Thus, we have obtained a H7N9 vaccine that protected both mice and guinea pigs against lethal H7N9 challenge and infection respectively.

Rigid removable cover for dorsal wound protection and tube fixation in pigs

Objective To report the design and benefits of a rigid polyethylenecover ‘shell’ for the protection of dorsal torso wounds andtube fixation in pigs.

Methods Open C-shaped polyethylene shells were designed toprotect wounds and dressings on the dorsum of pigs used inresearch into negative pressure dressing-assisted wound healing.The shells were designed to resist trauma and contamination, tobe comfortable and expansible, and to facilitate tube fixation andmanagement. Strap fixation was optimised during experimentation. Efficacy was assessed by direct observation of dressing andwound protection, tube integrity and by macroscopic and microscopicassessments of wound healing.

Results The shells effectively protected the wounds againstblunt and sharp trauma, were simple to remove and reapply, were well tolerated and allowed for growth of the pigs. Circumferentia lneck straps attached by lateral straps to the shells provedcritical. There was no wound infection or inflammation underlyingthe shells. Porting tubing via mid-dorsal holes in the shells andaffixing the tubing just cranial to these holes prevented tubedamage and traction, permitted tube management from outsidethe cages and allowed the pigs to move freely without becomingentangled.

Conclusion These shells effectively protected dorsal skinwounds and dressings, prevented tube damage and facilitatedtube management in pigs. Similar systems may be useful forother production animals for wound management and for tubemanagement with negative pressure wound healing, drain tubesor the delivery of nutrition, fluids or medications.

Dietary conjugated linoleic acid differentially alters fatty acid composition and increases conjugated linoleic acid content in porcine adipose tissue

Conjugated linoleic acids (CLA) have been shown to decrease body fat content in pigs. It is possible that feeding pigs diets rich in CLA may increase carcass lipid CLA to levels that could provide health benefits when included as a part of a healthy diet. Therefore, the aim of the present study was to determine whether dietary CLA supplementation has any effect on the fatty acid composition of subcutaneous and intramuscular adipose tissue in pigs. Thirty-five female cross bred (Large White X Landrace) pigs (initial weight 57·2 kg and initial P2 back fat 11·5 mm) were used in the present study. Pigs were housed individually and randomly allocated to one of six dietary treatments (0·00, 1·25, 2·50, 5·00, 7·50 and 10·00 g CLA55 (55 g CLA isomers/100 g total fatty acids; Natural Lipids Ltd, Hovdebygda, Norway)/kg)
and fed their respective diets for 8 weeks. Twelve CLA isomers in the diet and in pig tissue lipids were separated by Agþ-HPLC. CLA was incorporated at fivefold higher levels in subcutaneous fat as compared with intramuscular fat and in a dose-dependant manner. Overall, the transfer efficiency of CLA was maximized at 5·00 g CLA55/kg. However, there was clear selectivity in the uptake or incorporation of cis,trans-9,11 isomer over the trans,cis-10,12 isomer. In general, CLA supplementation produced significant changes in skeletal muscle and adipose tissue fatty acid composition, indicating that dietary CLA had a potent affect on lipid transport and metabolism in vivo. Significant increases in myristic, palmitic and palmitoleic acids and a reduction in arachidonic acid were observed, suggesting an alteration in
activity of Δ5-, Δ6- and Δ9-desaturases in pig adipose tissue. In conclusion, feeding pigs diets supplemented with CLA increases carcass lipid CLA, but also results in changes in the fatty acid profile in pig fat that could potentially outweigh the benefits of CLA.

Effects of dietary conjugated linoleic acid on haematological and humoral responses in the grower pig

The effects of conjugated linoleic acid (CLA) on the levels of total serum leucocytes, granulocytes including neutrophils, basophils, and eosinophils, as well as on monocytes and leucocytes were measured in pigs selected from a clean (minimal disease) herd. Thirty pigs were fed different rates of dietary CLA (0, 1.25, 2.5, 5.0, 7.5, and 10.0 g CLA-55/kg diet) for 8 weeks. Blood samples were collected at the end of the study for assessment of haematological and humoral responses to CLA supplementation. No difference in total white blood cells including the neutrophil, monocyte, and lymphocyte counts was observed among different dietary groups. A dose-dependent reduction (P = 0.02) in eosinophil concentrations suggests that CLA exerts anti-inflammatory activities. A 2-fold increase in the level of basophils was recorded in pigs fed lower levels of CLA (1.25 and 2.5 g CLA/kg diet) but the levels decreased gradually (P = 0.05) and were below the detection limit at the highest rate (10 g/kg) of CLA supplementation. The level of IgG was reduced by over 50% in CLA-fed pigs (P < 0.001), although the response was quadratic in nature (P < 0.001). T-cell population analysis showed that CD4+ cells tended (P = 0.06) to be reduced linearly with increasing inclusion of CLA in the diet. Our results suggest that dietary CLA modulates haematological and humoral responses in a dose-dependent manner.

Dietary conjugated linoleic acid improves carcass leanness without altering meat quality in the growing pig

One constraint facing the pig industry is that ad libitum feeding can often result in high levels of body fat and technologies which can reduce the ratio of lean to fat deposition in the pig are continually being explored. Conjugated linoleic acids have been shown to decrease body fat content in pigs. Therefore, the aim of this study was to determine whether dietary conjugated linoleic acids supplementation has any effect on meat quality and carcass characteristics in finisher pigs. Sixty female crossbred (Large White × Landrace) pigs (average initial weight 56.6 ± 1.9 kg and average initial P2 backfat 11.4 ± 1.3 mm) were used in the present study. Pigs were individually housed and randomly allocated to 1 of 6 dietary treatments: 0, 0.125, 0.25, 0.50, 0.75 or 1.0% (w/w) of conjugated linoleic acids-55. The wheat-based diets were formulated to contain 14.3 MJ DE and 9.3 g available lysine per kg and were fed ad libitum for 8 weeks. Pigs were slaughtered and meat quality was determined on the longissimus thoracis using standard techniques. Dietary conjugated linoleic acids reduced subcutaneous back fat in a linear manner with effects being most pronounced in the middle back fat layer. There was also a linear (P<0.001) decrease in intramuscular fat with increasing dietary conjugated linoleic acids supplementation. However, there was no effect of conjugated linoleic acids on subjective measures of marbling of the loin. Also, loin muscle ultimate pH (P = 0.94), lightness values (P = 0.46) subjective colour scores (P = 0.79), cooking loss (P = 0.71), drip loss (P = 0.40), shear force (P = 0.61) and subjective measures of wetness/firmness (P = 0.19) were unaffected. Dietary conjugated linoleic acids did not alter oxidation, as measured by the level of TBARs at day 1 post-slaughter (P = 0.38) or after 9 days of simulated retail display (P = 0.35). These data confirm that dietary conjugated linoleic acids can improve carcass quality by decreasing back fat depths without having any detrimental effects on meat quality.

Retinal sensitivity loss in third-generation n-3 PUFA-deficient rats

A previous study conducted in guinea pigs suggested that ingestion of diets high in EPA and DHA may result in suboptimal retinal function. The aim of the present study was to evaluate retinal function in pigmented (Long-Evans) rats, raised to a third generation on diets that were either deficient in n-3 PUFA or adequate (with the addition of DHA). Electroretinographic assessment employed full-field white flash stimulation. Photoreceptor responses were evaluated in terms of peak amplitudes and implicit times (a-wave, b-wave), intensity-response functions (Naka-Rushton), and the parameters of a model of transduction (P3). Retinal phospholipid FA composition was measured by capillary GLC. DHA levels were reduced by 55% in n-3-deficient animals compared with the n-3-adequate group, whereas the levels of docosapentaenoic acid n-6 were 44 times higher in n-3-deficient animals. The level of arachidonic acid was marginally higher (12.8%) in n-6-adequate animals. The n-3-deficient animals exhibited significantly reduced retinal sensitivity (σ and S values were both affected by 0.29 log units) and increased b-wave implicit times compared with those fed the n-3-adequate diet. These data suggest that n-3 PUFA are required for development of retinal sensitivity, more so than other indices of retinal function assessed by current methods, such as maximal response amplitude. However, the benefit for retinal function of adding preformed DHA to diets already replete in n-3 PUFA remains unclear.

CoQ10 conveys protection from oxidative stress in plasma but not skeletal muscle

Coenzyme Q10 (CoQ10) is commonly consumed as an antiaging supplement at doses of 30–210 mg/day. The aim of the study was to determine if CoQ10 alters markers of antioxidant status, oxidative damage, and gene expression in aging skeletal muscle. Female guinea pigs aged 26 months were supplemented for 6 weeks with CoQ10 at a human equivalent dose of 10 mg/kg/day. Body weight, plasma CoQ10 concentration, and WBC DNA abasic sites were measured at weeks 0, 2, 4, and 6 of the supplementation period. At the end of supplementation, concentrations of skeletal muscle CoQ10, glutathione, malondialdehyde, protein carbonyls, DNA abasic sites, activities of catalase and glutathione peroxidase, and the gene expression of cyctochrome c oxidase subunits were measured. Dietary supplementation with CoQ10 elevated plasma CoQ10 levels (pre 73 ± 3 nmol/L, post 581 ± 15 nmol/L, P < 0.05) and decreased abasic sites in WBC DNA (pre 16.8 ± 0.5 Ap/100000 bp, post 9.7 ± 0.4 Ap/100000 bp, P < 0.05). In contrast, all of the measures made in skeletal muscle were not different between groups (P > 0.05). These results indicate that dietary supplementation with CoQ10 at a dose of 10 mg/kg/day may be capable of increasing antioxidant protection and reducing oxidative damage in the plasma, but may have no effect in skeletal muscle.

Differential effects of natural palm oil, chemically and enzymatically-modified palm oil on weight gain, blood lipid metabolites and fat deposition in a pediatric pig model

Background: Increasing prevalence of obesity and overweight in the Western world, continue to be a major health threat and is responsible for increased health care costs. Dietary intervention studies show a strong positive association between saturated fat intake and the development of obesity and cardiovascular disease. This study investigated the effect of positional distribution of palmitic acid (Sn-1, 2 & 3) of palm oil on cardiovascular health and development of obesity, using weaner pigs as a model for young children.

Methods: Male and female weaner piglets were randomly allocated to 4 dietary treatment groups: 1) pork lard (LRD); 2) natural palm olein (NPO); 3) chemically inter-esterified PO (CPO) and 4) enzymatically inter-esterified PO (EnPO) as the fat source. Diets were formulated with 11% lard or with palm olein in order to provide 31% of digestible energy from fat in the diet and were balanced for cholesterol, protein and energy across treatments.

Results: From 8 weeks onwards, pigs on EnPO diet gained (P < 0.05) more weight than all other groups. Feed conversion efficiency (feed to gain) over the 12 week experimental period did not vary between treatment groups. Plasma LDL-C content and LDL-C/HDL-C ratio in pigs fed natural PO tended to be lower compared to all other diets. The natural PO lowered (P < 0.02) the plasma triglyceride (TG) content relative to the lard or EnPO diets, but was not different from the CPO diet. The natural PO diet was associated with lower (P < 0.05) saturated fat levels in subcutaneous adipose tissue than the CPO and EnPO diets that had lower saturated fat levels than the lard diet. Female pigs had lower lean and higher fat and fat:lean ratio in the body compared with male pigs. No difference in weight gain or blood lipid parameters was observed between sexes.

Conclusions: The observations on plasma TG, muscle and adipose tissue saturated fatty acid contents and back fat (subcutaneous) thickness suggest that natural palm oil may reduce deposition of body fat. In addition, dietary supplementation with natural palm oil containing palmitic acid at different positions in meat producing animals may lead to the production of meat and meat products with lower saturated fats. An increase in fat content and a decrease in lean content in female pigs resulted in an increased body fat:lean ratio but gender had no effect on blood lipid parameters or insulin concentrations.

Modelling the health impact of environmentally sustainable dietary scenarios in the UK

BACKGROUND/OBJECTIVES:


Food is responsible for around one-fifth of all greenhouse gas (GHG) emissions from products consumed in the UK, the largest contributor of which is meat and dairy. The Committee on Climate Change have modelled the impact on GHG emissions of three dietary scenarios for food consumption in the UK. This paper models the impact of the three scenarios on mortality from cardiovascular disease and cancer.
SUBJECTS/METHODS:


A previously published model (DIETRON) was used. The three scenarios were parameterised by fruit and vegetables, fibre, total fat, saturated fat, monounsaturated fatty acids, polyunsaturated fatty acids, cholesterol and salt using the 2008 Family Food Survey. A Monte Carlo simulation generated 95% credible intervals.
RESULTS:


Scenario 1 (50% reduction in meat and dairy replaced by fruit, vegetables and cereals: 19% reduction in GHG emissions) resulted in 36 910 (30 192 to 43 592) deaths delayed or averted per year. Scenario 2 (75% reduction in cow and sheep meat replaced by pigs and poultry: 9% reduction in GHG emissions) resulted in 1999 (1739 to 2389) deaths delayed or averted. Scenario 3 (50% reduction in pigs and poultry replaced with fruit, vegetables and cereals: 3% reduction in GHG emissions) resulted in 9297 (7288 to 11 301) deaths delayed or averted.
CONCLUSION:


Modelled results suggest that public health and climate change dietary goals are in broad alignment with the largest results in both domains occurring when consumption of all meat and dairy products are reduced. Further work in real-life settings is needed to confirm these results.

Early protection in sheep against intratypic heterologous challenge with serotype O foot-and-mouth disease virus using high-potency, emergency vaccine

In 2009-2011, spread of a serotype O foot-and-mouth disease virus (FMDV) belonging to the South East Asia topotype led to the culling of over 3.5 million cattle and pigs in Japan and Korea. The O1 Manisa vaccine (belonging to the Middle East-South Asian topotype) was used at high potency in Korea to limit the expansion of the outbreak. However, no data are available on the spread of this virus or the efficacy of the O1 Manisa vaccine against this virus in sheep. In this study, the early protection afforded with a high potency (>6 PD50) FMD O1 Manisa vaccine against challenge with the O/SKR/2010 virus was tested in sheep. Sheep (n=8) were vaccinated 4 days prior to continuous direct-contact challenge with donor sheep. Donor sheep were infected with FMDV O/SKR/2010 by coronary band inoculation 24h prior to contact with the vaccinated animals, or unvaccinated controls (n=4). Three of the four control sheep became infected, two clinically. All eight O1 Manisa vaccinated sheep were protected from clinical disease. None had detectable antibodies to FMDV non-structural proteins (3ABC), no virus was isolated from nasal swabs, saliva or oro-pharyngeal fluid and none became carriers. Using this model of challenge, sheep were protected against infection as early as 4 days post vaccination.

The effect of repeated boar exposure on cortisol secretion and reproduction in gilts

It has been proposed that short-term activation of the hypothalamo-pituitary adrenal axis, with a consequent increase in the secretion of cortisol, amy disrupt the endocrine events prior to ovulation and thereby impair reproduction in females. We investigated this concept in gilts in which oestrus was detected by introduction to boars, where intense physical contact is possible, or by applying pressure to the back of gilts (back-pressure test) during fence-line exposure to boars, where intense physical contact is prohibited. We expected that there would be a greater release of cortisol and that reproduction would be inhibited in gilts introduced to boars compared to gilts in which the back-pressure test was used. As expected, introduction of gilts to boars resulted in a significant transient increase in plasma concentrations of cortisol while there was no significant effect of using the back-pressure test on plasma cortisol. Nevertheless, introduction of gilts to boars did not impair reproduction and there was no effect of method of detecting oestrus on duration of oestrus, sexual receptivity, fertility or fecundity. The length of the oestrous cycle was decreased and ovulation rate increased in gilts that were introduced to boars compared to gilts that underwent the back-pressure test, indicating that introduction of gilts to boars may have stimulated these aspects of reproduction. These stimulatory effects may have been due to an increased exposure of gilts to sexual behaviour and stimuli from boars when introduced to boars and/or to stimulatory effects of the hypothalamo-pituitary adrenal axis on some aspects of reproduction.

Repeated acute activation of the hypothalamo-pituitary adrenal axis prior to and during estrus did not affect reproductive performance in gilts

We investigated the effects of repeated acute activation of the hypothalamo-pituitary adrenal axis, prior to and during estrus, on reproduction in gilts. Individual gilts (n = 24 per treatment) either served as controls or were subjected to daily acute stress ("negative handling," brief electric shock with a battery-operated prodder during confinement with the experimenter) commencing, on average, 8 days prior to estrus. Gilts subjected to negative handling had a significant elevation in plasma concentrations of cortisol that lasted at least 3-4 h, and these gilts were slower than control gilts to approach and interact with the experimenter in a standard test. Nevertheless, reproductive performance--as measured by sexual receptivity and proceptivity, ovulation, the percentage of gilts that became pregnant, the number of embryos 20-21 days after insemination, and the weight of embryos--was not affected by repeated acute activation of the hypothalamo-pituitary adrenal axis. Our results suggest that repeated acute activation of the hypothalamo-pituitary adrenal axis prior to and during estrus does not affect the factors that control estrus and ovulation in gilts.

Sustained but not repeated acute elevation of cortisol impaired the luteinizing hormone surge, estrus, and ovulation in gilts

We tested the hypothesis that sustained and repeated acute elevation of cortisol would impair the LH surge, estrus, and ovulation in gilts. Cortisol was injected intramuscularly, to achieve a sustained elevation of plasma concentrations of cortisol, or intravenously, to achieve an acute elevation of plasma concentrations of cortisol. Control gilts received i.m. injections of oil and i.v. injections of saline. These treatments were administered to gilts (n = 6 per treatment) at 12-h intervals from Days 7 to 11 of the estrous cycle until after estrus ceased or until Day 27 or 28 of the estrous cycle, whichever came first. The repeated acute elevation of cortisol had no effect on the LH surge, estrus, or ovulation. In contrast, when the elevation of cortisol was sustained, the LH surge, estrus, and ovulation were inhibited. We conclude that cortisol is capable of direct actions to impair reproductive processes in female pigs but that plasma concentrations of cortisol need to be elevated for a substantial period for this to occur.

Monitoring the ungulate prey of the Komodo dragon Varanus komodoensis: distance sampling or faecal counts?

Monitoring the abundances of prey is important for informing the management of threatened and endangered predators. We evaluated the usefulness of faecal counts and distance sampling for monitoring the abundances of rusa deer Rusa timorensis, feral pig Sus scrofa and water buffalo Bubalus bubalis, the three key prey of the Komodo dragon Varanus komodoensis, at 11 sites on five islands in and around Komodo National Park, eastern Indonesia. We used species-specific global detection functions and cluster sizes (i.e. multiple covariates distance sampling) to estimate densities of rusa deer and feral pig, but there were too few observations to estimate densities of water buffalo. Rusa deer densities varied from from 2.5 to 165.5 deer/km2 with coefficients of variation (CVs) of 15-105%. Feral pig densities varied from 0.0 to 25.2 pigs/km 2 with CVs of 25-106%. There was a positive relationship between estimated faecal densities and estimated population densities for both rusa deer and feral pig: the form of the relationship was non-linear for rusa deer, but there was similar support for linear and non-linear relationships for feral pig. We found that faecal counts were more useful when ungulate densities were too low to estimate densities with distance sampling. Faecal count methods were also easier for field staff to conduct than distance sampling. Because spatial and temporal variation in ungulate density is likely to influence the population dynamics of the Komodo dragon, we recommend that annual monitoring of ungulates in and around Komodo National Park be undertaken using distance sampling and faecal counts. The relationships reported here will also be useful for managers establishing monitoring programmes for feral pig, rusa deer and water buffalo elsewhere in their native and exotic ranges.