High Inclusion Rates Research Articles

Centrale coördinatie van een multicenterstudie als alternatief voor betaling per patiënt

Objective: Multicenter clinical trials can be organized in different ways. Multiple centers participated in the HEALTH trial (Hip Fracture Evaluation with ALternatives of Total Hip Arthroplasty versus Hemi- Arthroplasty). For the Dutch sites most study tasks are managed by a central trial coordinator, whereas Canadian and US sites use local study coordinators. The aim of this study was to analyze how these strategies affected trial performance.Design: Prospective observational study.Method: Data related to ethics approval, trial startup time, inclusion rate and percentage of completed follow-ups were collected for each hospital and compared. Data from pre-trial screening were compared with actual inclusion rates.Results: The median start-up time of the trial after obtaining ethics approval was shorter in the Netherlands than in Canada and the US (4.6 versus 11.6 weeks).The inclusion rate was similar in both groups (0.62 versus 0.64/month). The median percentage of enrolled patients in the Netherlands was 27.3% versus 17.0% in Canada/US. The actual inclusion rates were lower than expected from pre-trial screening. The percentage of effectuated follow-up visits was > 90% in both groups.Conclusion: In this study, central trial coordination contributed to faster trial start-up and higher inclusion rates, but had no effect on the effectuated followup visits. Central coordination is therefore a suitable alternative for appointing these tasks to local research assistants and per patient payment. Central coordination enables non-academic hospitals to participate in clinical trials. Limiting conditions for central coordination are budget availability, a manageable number of patients, and a manageable distance between participating sites.

The Nutritional Value of Quality Protein Maize for Weaner Pigs

This study was done to find out the potential and efficacy of Quality Protein Maize (QPM) as a substitute for normal maize variety in intensive pig production in an attempt to reduce the cost of production. Thirty-two weaner pigs were assigned to four treatment groups in a completely randomized block design with a 2×2 factorial arrangement of treatments. Blocking was done on initial weight and sex. The treatments were a high inclusion rate of both QPM and normal maize at 72.3% inclusion rate compared to a low inclusion rate of 64.3% in both cases. Water and feed was provided ad-libitum throughout the study period. Feed intake, water consumption, weight gain and mortality were recorded. Feed intake was more (P 0.05). The results indicated that feeding QPM to weaner pigs at a higher level of 72.3% inclusion level could command a higher food conversion efficiency and at a reduced cost of production.

Effects of carob bean gum on performance, nutrient digestibility and Salmonella enterica var. Enteritidis colonisation in chickens

Salmonella is presently one of the microorganisms of higher concern for food safety in poultry products. The present study examined the effect of feeding galactomannans from carob bean gum on nutrient digestibility and performance in chickens, and on the prevalence of Salmonella enterica var. Enteritidis in challenged animals. Four experiments were performed with either broiler or leghorn chickens, challenged with 106CFU (colony-forming units) of S. Enteritidis at 1day of life, and feeding carob bean gum at different concentrations (25, 50 or 100g/kg, depending on the experiment), alone or in combination with β-mannanase, cellulase or α-galactosidase at 8.3U/g; or feeding D-mannose at 25g/kg, or depolymerized carob bean gum or guar gum at 100mg/kg. Trials lasted 3or 4weeks. Body weight and feed intake were determined and feed conversion ratio calculated (feed:gain). Faeces were collected during the last week on trial for evaluation of nutrient balance (energy, lipids and protein), using chromium oxide as inert marker. Viscosity of the ileal content was also determined at the end of the second experiment. Salmonella presence in caeca was determined two and 3weeks after challenge. Performance and nutritive value of diets were impaired in birds fed carob bean gum, with higher effect at higher inclusion rates. D-mannose impaired performance variables only whereas depolymerized gums did not affect bird performance or nutritive value of the diets. Of the enzymes tested, only β-mannanase significantly decreased the viscosity of the intestinal contents of birds fed carob bean gum and partly counteracted the impairment in bird performance and the reduction in the nutritive value of the diets. The number of Salmonella-positive birds varied among experiments and was lower in the third week post-challenge compared to the second week post-challenge. However, the reduction in the number of Salmonella-positive birds was more constant and marked when carob bean gum was present in the diet. The inclusion of carob bean gum in the diet of chickens at the high concentrations used in the present experiment reduced the presence of Salmonella in challenged birds, but it also impaired performance and nutrient digestibility. These impairments were partially counteracted by the addition of β-mannanase to the diet. Carob bean gum might be used to reduce the incidence of Salmonella in chickens, while its negative effects on performance and nutrient digestibility could be counteracted by β-mannanase.

Control of Abscess Disease of Sheep by Concurrent Vaccination, Zinc Injection and Antiseptic Washing

Sixteen lambs ranging in a ge between 9-12 m onths with l ive body weight 30-32 kg were u sed in a n e xperiment with 12-week periods to det ermine the effects of dietary deep stack broiler litter level on growth performance. Deep s tack was prepared in an underground s ilo pi t (2*2*2m) for a period of month. Four concentrate rations were used compromising deep stacked broiler litter at a rate of 0, 15, 30 and 45% of ration in addition to other feed ingredients of molasses, sorghum, groundnut cake, wheat bran, groundnut hullus, limestone and salt. Dry matter i ntake as g/ kg m etabolic b ody weight were not found to be different from each other except for h igher inclusion rate wh ich increased ( P <0.05). At higher inclusion rate both to tal ga in a nd the average daily gain in creased (P <0.05). A lso feed conversion ratio was not a ffected by inclusion of deep stack broiler l itter excep t for t he hi gher inclusion rat e (P <0.05). When inclusion rat e o f deep stack broiler l itter i s increased the l ambs tend to consume more wat er. There was a s ignificant ( P <0.05) d ifference among rat ions on diges tibility of dry matter ( DMD), crude fibre (CFD) and A sh content (AshD). Animal fed on ration A and C had a h igher DMD, CFD and A shD than ration B and D. Hence there was no significant (P <0. 05) difference among rations on digestibility of organic mat ter (OMD), crude protein ( CPD), ether extract (EED), Ca and P. The nitrogen intake was increased while t he i nclusion rat e o f deep stack broiler l itter i ncreased. However there was a s ignificant (P <0. 05) difference among rations on N intake. Whereby there was no s ignificant difference (P <0. 05) among rat ions on f eaces N, u rine N and N-retention. There was a s ignificant (P <0.05) di fference in t he 3 pH and the concentration of NH -N in the rumen liquor a mong rations, w hich a higher v alue of N H3-N and pH was recorded for ration D. While there was no significant difference (P <0. 05) in concentration of VFA which a higher value for r ation A and D than ration B and C. The co st of one kg body weight gain was lowering as the b roiler l itter i nclusion rat e i ncreased and then raised at 45% inclusion rat e. It could be concluded that f eeding deep stacked broiler litter with the levels o f 1 5, 3 0 and 45% concentrate inclusion rate to lambs im pose no harmful effect o n their h ealth or c ausing a severe reduction in their body p erformance and it was shown t hat it is a saf e f eed without any determinant effects on l amb's health. Even more i t was a cheap feed and produced a reasonable gr owth rat e wi thout causing any remarkable decr ease i n dai ly feed intake.

INFLUENCE OF ω-3 FATTY ACIDS SUPPLEMENTED TO LAYING HENS' DIET ON LAYING PERFORMANCE

A group-control experiment for a period of 45 days was conducted in order to determine the effects of use of ω-3 fatty acids on the production and economic results of laying hens. A total of 1264 Lohmann Brown layers were randomly devided into 4 experimental treatments with 79 replicates (4 per cage, 316 hens per treatment). The first group was fed complete feed mixture for laying hens with standard raw material and chemical composition. The feed mixtures for treatments 2., 3. and 4. were supplemented with ω-3 fatty acids. The source of ω-3 fatty acids was a microalgae Schizochytrium spp., commercial product “DHA Gold” (Martek, USA) in quantities of 0.5, 0.7 and 1.0%, respectively. The use of ω-3 PUFA supplement in higher inclusion rates, had a positive influence on the laying intensity, significantly higher (p <0.01) in the experimental groups supplemented in the amount of 0.7 and 1.0%. Layers of all experimental groups fed supplemented feed mixtures had lower average egg weights (68.1, 68.7 and 68.4 g) compared to the control group (68.8 g). However, supplementation with higher inclusion rates of ω-3 product resulted in higher total egg mass during the experiment (743 and 764 kg) in the third and fourth experimental groups, compared to the control group (691.9 kg). Experimental groups with a higher inclusion of ω-3 PUFA (0.7 and 1.0%), achieved higher daily consumption of 0.16% and 0.51% in comparison to the control group, but the best feed conversion (2.38 and 2.32), while supplementation in the amount of 0.5% resulted in the weakest conversion in the experimental group 2 (2.63). The lowest feed cost per produced egg was achieved by the control group fed complete, unsupplemented feed. Using supplemented feed with addition of ω-3 PUFA – DHA above the 0.5%, a significant difference was observed regarding the productivity of laying hens.

Extending Rare-Variant Testing Strategies: Analysis of Noncoding Sequence and Imputed Genotypes

Next Generation Sequencing Technology has revolutionized our ability to study the contribution of rare genetic variation to heritable traits. However, existing single-marker association tests are underpowered for detecting rare risk variants. A more powerful approach involves pooling methods that combine multiple rare variants from the same gene into a single test statistic. Proposed pooling methods can be limited because they generally assume high-quality genotypes derived from deep-coverage sequencing, which may not be available. In this paper, we consider an intuitive and computationally efficient pooling statistic, the cumulative minor-allele test (CMAT). We assess the performance of the CMAT and other pooling methods on datasets simulated with population genetic models to contain realistic levels of neutral variation. We consider study designs ranging from exon-only to whole-gene analyses that contain noncoding variants. For all study designs, the CMAT achieves power comparable to that of previously proposed methods. We then extend the CMAT to probabilistic genotypes and describe application to low-coverage sequencing and imputation data. We show that augmenting sequence data with imputed samples is a practical method for increasing the power of rare-variant studies. We also provide a method of controlling for confounding variables such as population stratification. Finally, we demonstrate that our method makes it possible to use external imputation templates to analyze rare variants imputed into existing GWAS datasets. As proof of principle, we performed a CMAT analysis of more than 8 million SNPs that we imputed into the GAIN psoriasis dataset by using haplotypes from the 1000 Genomes Project.

Nationwide, population-based data from 11,074 ERCP procedures from the Swedish Registry for Gallstone Surgery and ERCP

The Swedish Registry for Gallstone Surgery and ERCP (GallRiks) is the first nationwide Web-based quality registry for gallstone surgery and ERCP in the world. In this article we report data from 11,074 ERCPs performed in 2007 and 2008. The aim of this study is to present outcomes, safety data, and success rates of ERCPs performed in Sweden. Data gathering from a medical record database. This study reviewed 11,074 ERCPs performed in 2007 and 2008. In GallRiks, data concerning surgery performed for gallstone disease as well as all ERCPs are recorded. The registry is approved by the Swedish Surgical Society and is based on an Internet platform with online data registration. The online program includes 30-day follow-up information as well as the opportunity to retrieve electronic reports on demand. The present data represent 76% of all ERCPs performed in Sweden in 2007 and 95% of those performed in 2008. The database also has been validated, indicating a complete match between the medical records and the database in 97.3% of ERCP cases. Cannulation success and perioperative and postoperative complications. A successful bile duct cannulation was achieved in 92% of the ERCPs performed. The presence of common bile duct stones was the predominant finding and was seen in 36.8% of examinations. Perioperative and postoperative complication rates were 2.5% and 9.8%, respectively. The rate of ERCP-induced pancreatitis was 2.7%, and the total 30-day mortality rate in the database was 5.9% but varied significantly among the different diagnostic groups. The indications for ERCP differed between high-volume and low-volume centers, indicating an adequate referral pattern of complex cases in Sweden. GallRiks registration is voluntary and thus not 100%. This makes selection bias a possibility. ERCP is widely used at Swedish hospitals, with acceptable cannulation success rates and perioperative and postoperative complication rates similar to established standards. GallRiks is a population-based nationwide registry with good data validity and high inclusion rates regarding ERCPs.

Effects of source and level of fish oil supplementation in late pregnancy on feed intake, colostrum production and lamb output of ewes

Supplementing pregnant ewes with fish oil to enhance the dietary supply of 20:4 n-6 and 22:6 n-3 has the potential to improve neonatal vigour and increase lamb survival rates. However, dietary fish oil has been shown to reduce colostrum production of ewes which can adversely affect lamb survival. To investigate the effects of source and level of fish oil in this response, 55 twin-bearing ewes were offered grass silage (0.5 kg dry matter per day) plus concentrates (0.5 kg/d) and supplemented with 0, 20 or 40 g/d herring (H) or salmon oil (S) during the final 6 weeks of pregnancy, giving a total of 5 treatments being control, H20, H40, S20 and S40. Salmon oil increased the supply of 18:2 n-6 (2.37) and 22:4 n-6 (1.98) but reduced the supply of 22:6 n-3 (0.84) relative to herring oil. Silage DM intake was marginally lower for S40 ewes ( P<0.05) but there were no dietary effects on ewe live weight or body condition score. Plasma non-esterified fatty acids (NEFA) ( P<0.05) and urea ( P<0.001) concentrations were elevated in ewes fed fish oil. Lambs born to control ewes had higher serum IgG concentrations than those fed herring oil ( P<0.01). Colostrum output at 10 h ( P<0.01) and total yield of colostrum ( P<0.05) were lower for fish oil-supplemented ewes. Concentrations of 10 h IgG ( P<0.05), 18 h fat ( P<0.001), 18 h total solids ( P<0.05) as well as outputs of fat ( P<0.05), protein ( P<0.01), casein ( P<0.05), IgG ( P<0.001) and total solids ( P<0.05) were reduced by feeding fish oil. Compared with controls, ewes fed herring oil had a higher 10 h lactose concentration ( P<0.05) while those fed salmon oil had lower outputs of 18 h protein ( P<0.05) and 18 h casein ( P<0.05). Offering 20 g/d, but not 40 g/d, fish oil increased the number of lambs weaned (+0.55 lambs/ewe; P=0.06) and the total output of weaned lamb (19.4 kg; P<0.05), but otherwise there were no effects of fish oil level and source on ewe or lamb performance. Results indicate that low levels of crude fish oil supplementation (up to 20 g/d) during late pregnancy improved lamb survival and output at weaning, but these benefits disappeared at higher inclusion rates.

Arginine and Vitamin E improve the antibody responses to infectious bursal disease virus (IBDV) and sheep red blood cells in broiler chickens

1. Dietary arginine (ARG) and vitamin E (VE) have been shown to improve immune responses in broiler chickens, but their combined effects have not been well documented. The objective of this study was to evaluate the combined effects of dietary ARG and VE on antibody responses to sheep red blood cell (SRBC, agglutination assay) inoculation in 13-d-old chicks, and antibody titres (ELISA) to infectious bursal disease virus (IBDV) before and after vaccination of 20-d-old chicks. 2. One-day-old broiler chicks were fed diets with normal (NARG, 12 g/kg of feed) or high (HARG, 22 g/kg of feed) inclusion rates of ARG, and three rates of VE (40, 80, or 200 mg/kg of feed; 40 mg being the supplement used in commercial diets) in a factorial arrangement. 3. Antibody titres to SRBC at 5, 8, and 12 d after inoculation were higher in chicks fed on the HARG diet than in those on NARG, and in chickens on VE80 compared with those on VE200 at 5, 8, and 12 d after inoculation. Antibody titres to the IBDV 2 days before and 19 d after vaccination were higher in chickens on HARG compared with those on NARG, and in chicks on VE80 compared to those on VE40 but similar to those on VE200. Conversely, 5 d after vaccination titres against IBDV were higher in chicks on NARG than in those on HARG, and in chickens on VE40 compared with those on VE80, yet similar to those on VE200. 4. These results show that diets with high ARG and high VE (80 mg/kg) improved the humoral-mediated immune response of broilers to IBDV and SRBC, suggesting it could be a strategy to improve vaccination protection and resistance to diseases.

An Assessment of the Suitability of Backyard Produced Compost as a Potting Soil

Current scientific knowledge of compost is largely derived from research into commercially produced green compost. This has shown that such compost tends to have high pH, high conductivity, and potential for organic and/or mineral pollutants and therefore can be problematic for use in growing media at high inclusion rates. Little work has been undertaken at an amateur composting scale and it is unclear whether these problems are prevalent in amateur-produced compost. This paper describes trials assessing the suitability as growing media of different composts produced using a range of amateur gardener methods. The resultant compost was then used to produce potting soil mixes with different compost inclusion ratios (with loam acting as the diluent) and assessed by growing tomatoes and lettuce. When comparing the effects of the compost mixes, the open vessels exhibited significantly higher weed germination counts than the wooden and plastic vessels. Turning the compost also significantly increased the weed count. In terms of seeds (lettuce and tomato), significantly lower germination counts were determined in the undiluted mixes when compared to the diluted mixes earlier in the assessment period. By the end of the assessment period these differences were reduced. By the final harvest, tomato heights and biomass were significantly greater in the undiluted mixes when compared to the diluted mixes and were comparable to the control mixes. Backyard produced compost would appear to have some value as a potting soil but the method of production needs to be taken into account when considering its use.

Divergent modulation of swine ileal microbiota by formic acid and methionine hydroxy analogue-free acid

Management of intestinal microbiota of monogastric animals has increased in importance since the ban of growth promoting antibiotics in many countries. Organic acids have been used as alternatives to antibiotics by many feed manufacturers. Regardless of the wide usage, the effect, dose response and mode of action of acids on intestinal microbes is poorly understood. In this study, we investigated the effects of dietary supplementation of three commonly used products, namely formic acid (FA) (90%), dl-methionine (DLM) (99%) and liquid methionine hydroxy analogue-free acid (88%), on ileal microbiota of pigs. Laboratory simulation system, mimicking swine ileum, was used to study the products at various concentrations and combinations. Furthermore, selected combinations were tested in a piglet trial to confirm the findings made in in vitro studies. FA turned out to have a dual effect on ileal microbiota. At concentrations below 0.5%, it significantly stimulated bacteria, but at higher inclusion rates it was highly inhibitory. This finding, which was consistent in in vitro and in vivo studies, implies that reducing the dose of FA does not lead to a diluted inhibitory effect, but in fact, an opposite, stimulatory effect on intestinal microbiota. It is highly important that feed compounders acknowledge this finding. Unlike FA, the inhibitory effect of methionine hydroxy analogue on ileal bacteria was linearly dose dependent and significant at inclusion levels above 0.2%, in vitro. Partial replacement of methionine hydroxy analogue by FA, or FA by methionine hydroxy analogue, led to an unpredictable outcome due to the dual effects of FA; e.g., a minor inclusion of added FA changed the inhibitory effect of methionine hydroxy analogue into microbial stimulation by FA. Inhibition of ileal microbiota by methionine hydroxy analogue was detected only in in vitro studies, suggesting that intact methionine hydroxy analogue may not have reached the ileum, in live animals. Therefore, if the target is to ensure the inhibitory effect of FA, the FA level in feed should be kept above 0.6%, and not reduced, if methionine hydroxy analogue is used as a methionine source instead of DLM. DLM was totally inert with regard to bacterial growth and metabolism, both in vitro and in vivo. The results of these studies reveal the importance of knowing how each acid product works. Inconsistent results in animal trials may have been partly due to quadratic dose–response effects of products, and unpredictable product combination effects.

Effects of using thermally treated lupins instead of soybean meal and rapeseed meal in total mixed rations on in vitro microbial yield and performance of dairy cows

The objective was to study whether thermally treated lupins (TTL) can replace solvent-extracted soybean meal (SBM) and rapeseed meal (RSM) in dairy cow rations. Three total mixed rations (TMR) were used. They differed in the inclusion of the main protein feeds (TTL alone, TTL + RSM and RSM + SBM) but were equal in organic matter digestibility and metabolizable energy content. In vitro organic matter fermentation was not significantly different between the TMR. Efficiency of microbial crude protein (MCP) synthesis was significantly higher for TMR RSM + SBM than for TTL. In vitro gas production potential was similar for the three TMR. The maximal rate of gas production was achieved later in TMR TTL than in RSM + SBM. Feed intake of dairy cows was significantly lower when TMR TTL was fed than when TMR TTL + RSM or RSM + SBM were fed. Milk yield was significantly lower with the high inclusion rate of TTL in comparison with the other TMR. The contents of milk protein and milk fat were significantly lower when the two TTL containing TMR were fed in comparison with the RSM + SBM ration. Effects of TTL inclusion on MCP synthesis may affect the amino acid supply to the duodenum of cows to a greater extent than differences in the degradability of feed proteins.

Quantification and visualization of three-dimensional inconsistency of the ventrointermediate nucleus of the thalamus in the Schaltenbrand-Wahren brain atlas

This work quantifies and visualises 3D inconsistencies of the ventrointermediate nucleus (VIM) of the thalamus, including the VIM externum (VIMe) and VIM internum (VIMi), in the Schaltenbrand-Wahren (SW) brain atlas. For each VIM, VIMe, VIMi the 3D models, 3D-A, 3D-C and 3D-S were reconstructed from the SW axial, coronal and sagittal microseries, respectively, by applying a shape-based method. All 3D models, placed in the SW coordinate system, were compared quantitatively in terms of location (centroids), size (volumes), shape (normalised eigen values), orientation (eigen vectors), and mutual spatial relationships (overlaps and inclusions). The reconstructed 3D models differ significantly in location, size, shape, and inclusion rate. The centroid of 3D-A/VIM differs considerably from those of 3D-C/VIM and 3D-S/VIM. The difference between the centroids of 3D-C/VIM and 3D-S/VIM is in laterality only: that of 3D-C/VIM is located more medially (11.85 mm) than that of 3D-S/VIM (14.62 mm). 3D-A/VIM has the smallest volume (69.00 mm(3)); 3D-C/VIM is 3.71 and 3D-S/VIM 3.89 times larger. The overlap is also highly variable: 104.88 mm(3) for 3D-C/VIM with 3D-S/VIM, and very low (3.22 and 7.45 mm(3)) when 3D-A/VIM is involved. The highest inclusion rate is for 3D-C/VIM with 3D-S/VIM (39.10 and 40.97%) and the lowest for 3D-A/VIM with 3D-C/VIM (1.26 and 4.66%). The centroid of 3D-A/VIMe differs noticeably from those of 3D-C/VIMe and 3D-S/VIMe. The difference between the centroids of 3D-C/VIMe and 3D-S/VIMe is mainly in laterality: that of 3D-C/VIMe is located more medially (12.91 mm) than that of 3D-S/VIMe (16.65 mm). 3D-A/VIMe has the smallest volume (49.87 mm(3)); 3D-S/VIMe is 3.24 and 3D-C/VIMe 3.36 times larger. The overlap sizes are low: 32.72 mm(3) for 3D-C/VIMe with 3D-S/VIMe, and very low (1.32 and 2.01 mm(3)) when 3D-A/VIMe is involved. The inclusion rates are also low: the highest is for 3D-C/VIMe with 3D-S/VIMe (19.53 and 20.29%) and the lowest for 3D-A/VIMe with 3D-C/VIMe (1.19 and 4.01%). Lateral scaling of the coronal microseries by 1.2897 to match the 3D-C/VIMe and 3D-S/VIMe centroids increases the inclusion rates for the sagittal microseries by more than twice. The volume of scaled 3D-C enlarges to 216.24 mm(3) which is 1.34 bigger than that of 3D-S. There are substantial differences among the centroids of 3D-A/VIMi, 3D-C/VIMi and 3D-S/VIMi. The centroid of 3D-A/VIMi is located more anteriorly (-1.92 mm) than that of 3D-C/VIMi (-5.02 mm). The centroid of 3D-A/VIMi is located more ventrally (2.88 mm) than those of 3D-C/VIMi and 3D-S/VIMi (each at 5.34 mm). 3D-A/VIMi has the smallest volume (19.75 mm(3)); 3D-S/VIMi is 3.23 and 3D-C/VIMi 4.30 times larger. 3D-A/VIMi practically does not overlap with 3D-C/VIMi and 3D-S/VIMi. The inclusion rates for 3D-C/VIMi with 3D-S/VIMi are medium (32.63 and 43.43%). Each VIM, VIMe, VIMi as reconstructed from the SW atlas has a significant 3D inaccuracy within each orientation and across them. Therefore, absolute and direct reliance on the original SW atlas is unreliable and unsafe, and this atlas has to be used with great care and understanding of its strengths and limitations.

High inclusion rate of wet corngluten feed on performance oflate-lactation holstein cows:preliminary results (2008)

A novel diet formulation strategy incorporating wet corn gluten feed at 47% of diet dry matter was evaluated in late-lactation cows. Diets were formulated for similar protein and energy concentrations with dramatic differences in forage sources. Milk fat and protein concentrations increased with the high wet corn gluten feed inclusion rate, and this diet tended to increase milk fat yield. The preliminary work indicates that very low cost rations incorporating wet corn gluten feed may be formulated to maintain milk production, at least in late-lactation cows.

Developing organisational ‘off‐the‐shelf’ capacity: Continued implications for tutors who wish to increase their re‐use of electronically delivered time‐based media

Higher inclusion rate of different media types within technology‐supported learning scenarios is becoming more necessary for higher education, as it seeks to attract more technologically‐minded students and still offer effective learning. An ‘off‐the‐shelf’ model is needed, for making third‐party, non‐text‐based, electronic resources available to academic staff who are building courses, but is shown to still be some way off. Ideally this type of model should allow independent, legal use of such resources by academic staff who rely predominantly on standardised forms of organisational services. When achieved, less‐intensive day‐to‐day support should be required per learning scenario developed so that use of different media types becomes more scaleable than at present. This paper specifically concentrates on aspects related to time‐based media (TBM).

Immunocompetence in organically fed finishing pigs: Effect of corn cob mix

Two consecutive experiments were performed to evaluate the effects on the immune response of corn cob mix (CCM) in an organic pig diet. The immunoglobulin (Ig) M, IgA and IgG responses against an intramuscularly injected model antigen, bovine thyroglobulin, were used as indicator. The experiments were performed in an organic barn with nine pens of four crossbred pigs (two barrows and two sows) from 45 kg to slaughter. In the first experiment, the organic concentrate was mixed with organic CCM-silage to obtain three concentrate: CCM ratios of 100:0, 80:20 and 60:40 (w:w). In the second experiment, three concentrates were produced to obtain diets with equal nutrient levels on a dry matter basis after 0%, 20% and 40% CCM inclusion. Higher inclusion rates of CCM in the ration were accompanied by lower thyroglobulin-specific IgG responses. These effects could not be attributed to one specific component of the CCM, such as fatty acid composition, although there was a degree of correlation with lower vitamin A concentrations. Mycotoxin concentrations were absent or minimal. The study indicated that dietary ingredient composition may affect immunocompetence.

Alternative plant protein sources in sea bass diets

A control diet (C) containing animal protein (mainly fish meal) was compared with 6 experimental diets containing different plant proteins (soybean meal, SM; rapeseed meal, RM; potato protein concentrate, PPC and a mix of the three vegetable protein sources, M). The plant protein replaced either 25 (1) or 50 (2)% of the animal protein with the exception of diet RM2 where the substitution rate was lowered to 35%, and in diet M where 55% of the total protein given was replaced in equal amounts by the three plant proteins. For the growth trial, which lasted 97 days, 528 European sea bass (initial live weight 107 ± 0,06g), distributed among 24 fibreglass tanks with three replicates per treatment, were used. The pelleted feed was distributed 5 times per day using an automatic dispenser. Energy, crude protein and crude fat digestibility values for fish meal and soybean meal were similar and not statistically different while the values for rapeseed meal and potato protein concentrate were significantly lower. Digestive utilization for NFE was higher in fish meal and decreased significantly in soybean meal, rapeseed meal and even more noticeably in potato protein concentrate. Diet digestibility values showed a similar trend with a clear worsening effect at the higher inclusion rates used. Diet M gave digestibility coefficients lower than those observed with diets C, SM1, SM2, RS1 and RS2 and higher than those of diets PPC1 and PPC2. Fish fed a diet in which 25% of the total protein was replaced by soybean had similar performances to those of the control group. On the other hand, sea bass fed diets SM2, RS1, RS2 and M had lower growth rates and worse feed utilization than those observed with the control. Finally, specific growth rates and food conversion efficiency in sea bass fed diets containing potato protein concentrate were poor because of the low palatability. These results show that soybean meal can substitute up to 25% of the total protein of the diet without any negative effect on sea bass performance.

Assessment of Hull-less Barley as a Locally Grown Swine Feed Ingredient in the Mid-Atlantic Region of the United States

Crossbred pigs (six replicate pens of four pigs per treatment, avg. initial BW = 38 kg) were used in a 6-wk growth and digestibility trial to assess a hull-less barley adapted for the mid Atlantic region of the U.S. as the primary ingredient in pelleted diets for growing pigs. There were five experimental diets: 1) a corn-soybean meal-based diet, 2) a diet containing 46% hull-less barley and 1.6% added fat, 3) a diet containing 41% hulled barley and 4.1% added fat, 4) a diet containing 46% hulled barley and 1.6% added fat, and 5) a diet containing 46% wheat and 0.68% added fat. For diets based on small grains, a fixed inclusion rate of 25% corn was used. With the exception of Diet 4, all diets were formulated to be iso-lysinic and iso-caloric. Diet type had no effect (P>0.10) on ADFI or ADG. Pigs fed the hulled barley, high-fat diet (Diet 3) had slightly improved feed efficiency (P<0.05) relative to pigs fed the corn, hull-less barley or hulled barley, low-fat diets. Only minor differences in digestibility of DM, energy, and protein were observed among the corn, hull-less barley, hulled barley, high-fat, and wheat diets. The digestibility of these components in the hulled barley, low-fat diet (Diet 4) was 3.9 to 6.9 percentage units less (P<0.05) than in the other diets. These results demonstrate that good quality hulled and hull-less barley adapted for the mid-Atlantic region of the U.S. can be used at a relatively high inclusion rate in pelleted grower pig diets and produce growth performance comparable with similar diets based mainly on corn or wheat.

Tolerance for excess basic zinc chloride and basic copper chloride in chicks

1. Four chick experiments were conducted to determine toxicity estimates for basic zinc chloride (BZC) and basic copper chloride (BCC), now being used as sources for these minerals. 2. In experiment 1, New Hampshire × Columbian crossbred chicks were fed 0, 500, 1000, 1500, 3000 and 5000 mg Zn/kg from BZC (Zn5Cl2(OH)8). Broken-line regression analysis showed that the minimal toxic break points for chick weight gain and gain:food were 1720 and 2115 mg Zn/kg, respectively. 3. Crossbred chicks were fed 0, 150, 250, 500, 750 and 1000 mg Cu/kg from BCC (Cu2(OH)3C) in experiment 2. Regression analysis indicated that the minimal toxic break points for chick weight gain and gain:food were 642 and 781 mg Cu/kg, respectively. 4. In experiment 3, commercial broiler chicks were fed 0, 1500, 2000 and 2500 mg supplemental Zn/kg from BZC or 0, 500, 650 and 800 mg supplemental Cu/kg from BCC. Broiler chicks fed those high inclusion rates of Zn did not show reduced weight gain in comparison to chicks fed no supplemental Zn. All high concentrations of supplemental Cu depressed chick weight gain in comparison to control chicks. 5. Experiment 4 involved two separate 4 × 2 factorial designs with supplemental Zn (0, 2500, 3500 and 4500 mg/kg) or Cu (0, 500, 750 and 1000 mg/kg) and two breeds of chicks (crossbred and commercial). Significant interactions for weight gain, food intake, gain:food and liver Cu suggested that the crossbred and commercial chicks responded differently to high concentrations of supplementary dietary Cu.

The effect of dietary chicken egg-yolk antibodies on the clinical response in weaned pigs challenged with a K88+ Escherichia coli isolate

Objectives: To determine if supplementing the diet of weaned pigs with a specific chicken egg-yolk-antibody product would protect against experimentally induced colibacillosis. Methods: Four treatment groups of 12 newly weaned pigs (approximately 22 days old) were fed either a control diet (Groups 1 and 2) or the same diet containing chicken egg-yolk antibodies (IgY) at inclusion rates of 0.32% (Group 3) and 3.2% (Group 4). Pigs in Groups 2, 3, and 4 were challenged with 5 mL of a suspension containing 1011 colony forming units per mL of a K88+ isolate of Escherichia coli. Results: Pigs in Group 1 (unchallenged controls) did not develop diarrhea. In the three groups challenged with E coli, pigs developed watery diarrhea and dehydration. Prevalence and severity of clinical signs were similar in all three groups. No appreciable levels of IgY were detected either in treated or control pigs by ELISA testing of small intestine content. Discussion: The E coli challenge was successful in creating a clinical response similar to field cases. The presence of chicken egg-yolk antibodies in the ration did not appear to be effective in preventing the disease. It is possible that IgY activity is greatly reduced by gastric acid and pepsin, and therefore, even at high inclusion rates, egg-yolk antibodies may not be efficacious in pigs as old as 3 to 4 weeks of age. Implications: Supplementation of chicken egg-yolk-antibody products may not be effective in controlling postweaning E coli diarrhea.