Now showing items 21-40 of 1423

    • Improving the Yield and Quality of Arable Crops in Organic Production Systems

      Crowley, J.G. (Teagasc, 2005-04-01)
      Ireland's ability to supply organic arable products to meet future market requirements depends on the provision of scientific quantitative information on the production of these crops. The conversion of an 8-ha site at Oak Park is described. The establishment of a single stockless 7-year rotation (wheat, potatoes, oats, legume, spring barley followed by two years’ grass/clover lea) with three replicates is described. The results of the first series of experiments are presented and the possible implications discussed.
    • Phylogenetic and functional potential links pH and N2O emissions in pasture soils

      Samad, Sainur; Biswas, Ambarish; Bakken, Lars R.; Clough, Timothy J.; de Klein, Cecilia A.M.; Richards, Karl G.; Lanigan, Gary J.; Morales, Sergio E. (Nature Publishing Group, 2016-10-26)
      Denitrification is mediated by microbial, and physicochemical, processes leading to nitrogen loss via N2O and N2 emissions. Soil pH regulates the reduction of N2O to N2, however, it can also affect microbial community composition and functional potential. Here we simultaneously test the link between pH, community composition, and the N2O emission ratio (N2O/(NO + N2O + N2)) in 13 temperate pasture soils. Physicochemical analysis, gas kinetics, 16S rRNA amplicon sequencing, metagenomic and quantitative PCR (of denitrifier genes: nirS, nirK, nosZI and nosZII) analysis were carried out to characterize each soil. We found strong evidence linking pH to both N2O emission ratio and community changes. Soil pH was negatively associated with N2O emission ratio, while being positively associated with both community diversity and total denitrification gene (nir & nos) abundance. Abundance of nosZII was positively linked to pH, and negatively linked to N2O emissions. Our results confirm that pH imposes a general selective pressure on the entire community and that this results in changes in emission potential. Our data also support the general model that with increased microbial diversity efficiency increases, demonstrated in this study with lowered N2O emission ratio through more efficient conversion of N2O to N2.
    • Carbon cycling in temperate grassland under elevated temperature

      Jansen-Willems, Anne B.; Lanigan, Gary; Grunhage, Ludger; Muller, Christoph (Wiley, 2016-11-01)
      An increase in mean soil surface temperature has been observed over the last century, and it is predicted to further increase in the future. The effect of increased temperature on ecosystem carbon fluxes in a permanent temperate grassland was studied in a long-term (6 years) field experiment, using multiple temperature increments induced by IR lamps. Ecosystem respiration (R-eco) and net ecosystem exchange (NEE) were measured and modeled by a modified Lloyd and Taylor model including a soil moisture component for R-eco (average R2 of 0.78) and inclusion of a photosynthetic component based on temperature and radiation for NEE (R2 = 0.65). Modeled NEE values ranged between 2.3 and 5.3 kg CO2 m−2 year−1, depending on treatment. An increase of 2 or 3°C led to increased carbon losses, lowering the carbon storage potential by around 4 tonnes of C ha−1 year−1. The majority of significant NEE differences were found during night-time compared to daytime. This suggests that during daytime the increased respiration could be offset by an increase in photosynthetic uptake. This was also supported by differences in δ13C and δ18O, indicating prolonged increased photosynthetic activity associated with the higher temperature treatments. However, this increase in photosynthesis was insufficient to counteract the 24 h increase in respiration, explaining the higher CO2 emissions due to elevated temperature.
    • Novel Graphical Analyses of Runs of Homozygosity among Species and Livestock Breeds

      Iacolina, Laura; Stronen, Astrid V.; Pertoldi, Cino; Tokarska, Małgorzata; Norgaard, Louise S.; Munoz, Joaquin; Kjaersgaard, Anders; Ruiz-Gonzalez, Aritz; Kaminski, Stanislaw; Purfield, Deirdre C (Hindawi, 2016)
      Runs of homozygosity (ROH), uninterrupted stretches of homozygous genotypes resulting from parents transmitting identical haplotypes to their offspring, have emerged as informative genome-wide estimates of autozygosity (inbreeding). We used genomic profiles based on 698 K single nucleotide polymorphisms (SNPs) from nine breeds of domestic cattle (Bos taurus) and the European bison (Bison bonasus) to investigate how ROH distributions can be compared within and among species. We focused on two length classes: 0.5–15 Mb to investigate ancient events and >15 Mb to address recent events (approximately three generations). For each length class, we chose a few chromosomes with a high number of ROH, calculated the percentage of times a SNP appeared in a ROH, and plotted the results. We selected areas with distinct patterns including regions where (1) all groups revealed an increase or decrease of ROH, (2) bison differed from cattle, (3) one cattle breed or groups of breeds differed (e.g., dairy versus meat cattle). Examination of these regions in the cattle genome showed genes potentially important for natural and human-induced selection, concerning, for example, meat and milk quality, metabolism, growth, and immune function. The comparative methodology presented here permits visual identification of regions of interest for selection, breeding programs, and conservation.
    • Isolation and characterisation of κ-casein/whey protein particles from heated milk protein concentrate and role of κ-casein in whey protein aggregation

      Gaspard, Sophie J.; Auty, Mark A.E.; Kelly, Alan L.; O'Mahony, James A.; Brodkorb, Andre (Elsevier, 2017-06-12)
      Milk protein concentrate (79% protein) reconstituted at 13.5% (w/v) protein was heated (90 °C, 25 min, pH 7.2) with or without added calcium chloride. After fractionation of the casein and whey protein aggregates by fast protein liquid chromatography, the heat stability (90 °C, up to 1 h) of the fractions (0.25%, w/v, protein) was assessed. The heat-induced aggregates were composed of whey protein and casein, in whey protein:casein ratios ranging from 1:0.5 to 1:9. The heat stability was positively correlated with the casein concentration in the samples. The samples containing the highest proportion of caseins were the most heat-stable, and close to 100% (w/w) of the aggregates were recovered post-heat treatment in the supernatant of such samples (centrifugation for 30 min at 10,000 × g). κ-Casein appeared to act as a chaperone controlling the aggregation of whey proteins, and this effect was stronger in the presence of αS- and β-casein.
    • A Simple Method for the Purification of Nisin

      Gough, Ronan; Gomez-Sala, Beatriz; O'Connor, Paula M.; Rea, Mary C.; Miao, Song; Hill, Colin; Brodkorb, Andre (Springer, 2017-05-29)
      Nisin, an antimicrobial peptide showing activity against a broad range of Gram-positive bacteria, is widely used as a food preservative and has potential as a therapeutic for a range of infectious diseases. Here, we present a simple purification method, based on a salting-out approach, which can produce a powder containing ∼33% nisin, from a nisin-producing culture in a whey permeate-based medium. This process removes over 99% of the lactic acid, NaCl, lactose and non-nisin proteins from the cell-free culture supernatant. The approach can also enrich a commonly used commercial nisin preparation over 30-fold to a purity of ∼58%. These are higher purities than comparable published methods. The simplicity of this approach facilitates its use in research and also its scale-up.
    • Bacteriocin-Antimicrobial Synergy: A Medical and Food Perspective

      Mathur, Harsh; Field, Des; Rea, Mary C.; Cotter, Paul D.; Hill, Colin; Ross, R.Paul (Frontiers, 2017-06-29)
      The continuing emergence of multi-drug resistant pathogens has sparked an interest in seeking alternative therapeutic options. Antimicrobial combinatorial therapy is one such avenue. A number of studies have been conducted, involving combinations of bacteriocins with other antimicrobials, to circumvent the development of antimicrobial resistance and/or increase antimicrobial potency. Such bacteriocin-antimicrobial combinations could have tremendous value, in terms of reducing the likelihood of resistance development due to the involvement of two distinct mechanisms of antimicrobial action. Furthermore, antimicrobial synergistic interactions may also have potential financial implications in terms of decreasing the costs of treatment by reducing the concentration of an expensive antimicrobial and utilizing it in combination with an inexpensive one. In addition, combinatorial therapies with bacteriocins can broaden antimicrobial spectra and/or result in a reduction in the concentration of an antibiotic required for effective treatments to the extent that potentially toxic or adverse side effects can be reduced or eliminated. Here, we review studies in which bacteriocins were found to be effective in combination with other antimicrobials, with a view to targeting clinical and/or food-borne pathogens. Furthermore, we discuss some of the bottlenecks which are currently hindering the development of bacteriocins as viable therapeutic options, as well as addressing the need to exercise caution when attempting to predict clinical outcomes of bacteriocin-antimicrobial combinations.
    • Whole-Genome Shotgun Sequence of Salmonella bongori, First Isolated in Northwestern Italy

      Romano, Angelo; Bellio, Alberto; Macori, Guerrino; Cotter, Paul D; Manila Bianchi, Daniela; Gallina, Silvia; Decastelli, Lucia (American Society for Microbiology, 2017-07-06)
      This study describes the whole-genome shotgun sequence of Salmonella bongori 48:z35:–, originally isolated from a 1-year-old symptomatic patient in northwest Italy, a typically nonendemic area. The draft genome sequence contained 4.56 Mbp and the G+C content was 51.27%.
    • Draft Genome Sequences of Three Lactobacillus paracasei Strains, Members of the Nonstarter Microbiota of Mature Cheddar Cheese

      Stefanovic, Ewelina; Fitzgerald, Gerald; McAuliffe, Olivia (American Society for Microbiology, 2017-07-20)
      Lactobacillus paracasei strains are common members of the nonstarter microbiota present in various types of cheeses. The draft genome sequences of three strains isolated from mature cheddar cheeses are reported here.
    • Future Protein Supply and Demand: Strategies and Factors Influencing a Sustainable Equilibrium

      Henchion, Maeve; Hayes, Maria; Mullen, Anne Maria; Fenelon, Mark; Tiwari, Brijesh (MDPI, 2017-07-20)
      A growing global population, combined with factors such as changing socio-demographics, will place increased pressure on the world’s resources to provide not only more but also different types of food. Increased demand for animal-based protein in particular is expected to have a negative environmental impact, generating greenhouse gas emissions, requiring more water and more land. Addressing this “perfect storm” will necessitate more sustainable production of existing sources of protein as well as alternative sources for direct human consumption. This paper outlines some potential demand scenarios and provides an overview of selected existing and novel protein sources in terms of their potential to sustainably deliver protein for the future, considering drivers and challenges relating to nutritional, environmental, and technological and market/consumer domains. It concludes that different factors influence the potential of existing and novel sources. Existing protein sources are primarily hindered by their negative environmental impacts with some concerns around health. However, they offer social and economic benefits, and have a high level of consumer acceptance. Furthermore, recent research emphasizes the role of livestock as part of the solution to greenhouse gas emissions, and indicates that animal-based protein has an important role as part of a sustainable diet and as a contributor to food security. Novel proteins require the development of new value chains, and attention to issues such as production costs, food safety, scalability and consumer acceptance. Furthermore, positive environmental impacts cannot be assumed with novel protein sources and care must be taken to ensure that comparisons between novel and existing protein sources are valid. Greater alignment of political forces, and the involvement of wider stakeholders in a governance role, as well as development/commercialization role, is required to address both sources of protein and ensure food security.
    • The Fungal Frontier: A Comparative Analysis of Methods Used in the Study of the Human Gut Mycobiome

      Huseyin, Chloe E.; Cabrera Rubio, Raul; O'Sullivan, Orla; Cotter, Paul D; Scanlan, Pauline D. (Frontiers, 2017-07-31)
      The human gut is host to a diverse range of fungal species, collectively referred to as the gut “mycobiome”. The gut mycobiome is emerging as an area of considerable research interest due to the potential roles of these fungi in human health and disease. However, there is no consensus as to what the best or most suitable methodologies available are with respect to characterizing the human gut mycobiome. The aim of this study is to provide a comparative analysis of several previously published mycobiome-specific culture-dependent and -independent methodologies, including choice of culture media, incubation conditions (aerobic versus anaerobic), DNA extraction method, primer set and freezing of fecal samples to assess their relative merits and suitability for gut mycobiome analysis. There was no significant effect of media type or aeration on culture-dependent results. However, freezing was found to have a significant effect on fungal viability, with significantly lower fungal numbers recovered from frozen samples. DNA extraction method had a significant effect on DNA yield and quality. However, freezing and extraction method did not have any impact on either α or β diversity. There was also considerable variation in the ability of different fungal-specific primer sets to generate PCR products for subsequent sequence analysis. Through this investigation two DNA extraction methods and one primer set was identified which facilitated the analysis of the mycobiome for all samples in this study. Ultimately, a diverse range of fungal species were recovered using both approaches, with Candida and Saccharomyces identified as the most common fungal species recovered using culture-dependent and culture-independent methods, respectively. As has been apparent from ecological surveys of the bacterial fraction of the gut microbiota, the use of different methodologies can also impact on our understanding of gut mycobiome composition and therefore requires careful consideration. Future research into the gut mycobiome needs to adopt a common strategy to minimize potentially confounding effects of methodological choice and to facilitate comparative analysis of datasets.
    • Synergistic Nisin-Polymyxin Combinations for the Control of Pseudomonas Biofilm Formation

      Field, Des; Seisling, Nynke; Cotter, Paul D.; Ross, R. Paul; Hill, Colin (Frontiers, 2016-10-26)
      The emergence and dissemination of multi-drug resistant pathogens is a global concern. Moreover, even greater levels of resistance are conferred on bacteria when in the form of biofilms (i.e., complex, sessile communities of bacteria embedded in an organic polymer matrix). For decades, antimicrobial peptides have been hailed as a potential solution to the paucity of novel antibiotics, either as natural inhibitors that can be used alone or in formulations with synergistically acting antibiotics. Here, we evaluate the potential of the antimicrobial peptide nisin to increase the efficacy of the antibiotics polymyxin and colistin, with a particular focus on their application to prevent biofilm formation of Pseudomonas aeruginosa. The results reveal that the concentrations of polymyxins that are required to effectively inhibit biofilm formation can be dramatically reduced when combined with nisin, thereby enhancing efficacy, and ultimately, restoring sensitivity. Such combination therapy may yield added benefits by virtue of reducing polymyxin toxicity through the administration of significantly lower levels of polymyxin antibiotics.
    • Stress and immunological response of heifers divergently ranked for residual feed intake following an adrenocorticotropic hormone challenge

      Kelly, A. K; Lawrence, P.; Earley, Bernadette; Kenny, David A.; McGee, Mark (Biomed Central, 2017-08-08)
      Background When an animal is exposed to a stressor, metabolic rate, energy consumption and utilisation increase primarily through activation of the hypothalamic-pituitary-adrenal (HPA) axis. Changes to partitioning of energy by an animal are likely to influence the efficiency with which it is utilised. Therefore, this study aimed to determine the physiological stress response to an exogenous adrenocorticotropic hormone (ACTH) challenge in beef heifers divergently ranked on phenotypic residual feed intake (RFI). Results Data were collected on 34 Simmental weaning beef heifers the progeny of a well characterized and divergently bred RFI suckler beef herd. Residual feed intake was determined on each animal during the post-weaning stage over a 91-day feed intake measurement period during which they were individually offered adlibitum grass silage and 2 kg of concentrate per head once daily. The 12 highest [0.34 kg DM/d] and 12 lowest [−0.48 kg DM/d] ranking animals on RFI were selected for use in this study. For the physiological stress challenge heifers (mean age 605 ± 13 d; mean BW 518 ± 31.4 kg) were fitted aseptically with indwelling jugular catheters to facilitate intensive blood collection. The response of the adrenal cortex to a standardised dose of ACTH (1.98 IU/kg metabolic BW0.75) was examined. Serial blood samples were analysed for plasma cortisol, ACTH and haematology variables. Heifers differing in RFI did not differ (P = 0.59) in ACTH concentrations. Concentration of ACTH peaked (P < 0.001) in both RFI groups at 20 min post-ACTH administration, following which concentration declined to baseline levels by 150 min. Similarly, cortisol systemic profile peaked at 60 min and concentrations remained continuously elevated for 150 min. A RFI × time interaction was detected for cortisol concentrations (P = 0.06) with high RFI heifers had a greater cortisol response than Low RFI from 40 min to 150 min relative to ACTH administration. Cortisol response was positively associated with RFI status (r = 0.32; P < 0.01). No effect of RFI was evident for neutrophil, lymphocytes, monocyte, eosinophils and basophil count. Plasma red blood cell number (6.07 vs. 6.23; P = 0.02) and hematocrit percentage (23.2 vs. 24.5; P = 0.02) were greater for low than high RFI animals. Conclusions Evidence is provided that feed efficiency is associated with HPA axis function and susceptibility to stress, and responsiveness of the HPA axis is likely to contribute to appreciable variation in the efficiency feed utilisation of cattle.
    • Illumina MiSeq 16S amplicon sequence analysis of bovine respiratory disease associated bacteria in lung and mediastinal lymph node tissue

      Johnston, Dayle; Earley, Bernadette; Cormican, Paul; Murray, Gerard; Kenny, David A; Waters, Sinead M; McGee, Mark; Kelly, Alan K; McCabe, Matthew S (Biomed Central, 2017-05-02)
      Background Bovine respiratory disease (BRD) is caused by growth of single or multiple species of pathogenic bacteria in lung tissue following stress and/or viral infection. Next generation sequencing of 16S ribosomal RNA gene PCR amplicons (NGS 16S amplicon analysis) is a powerful culture-independent open reference method that has recently been used to increase understanding of BRD-associated bacteria in the upper respiratory tract of BRD cattle. However, it has not yet been used to examine the microbiome of the bovine lower respiratory tract. The objective of this study was to use NGS 16S amplicon analysis to identify bacteria in post-mortem lung and lymph node tissue samples harvested from fatal BRD cases and clinically healthy animals. Cranial lobe and corresponding mediastinal lymph node post-mortem tissue samples were collected from calves diagnosed as BRD cases by veterinary laboratory pathologists and from clinically healthy calves. NGS 16S amplicon libraries, targeting the V3-V4 region of the bacterial 16S rRNA gene were prepared and sequenced on an Illumina MiSeq. Quantitative insights into microbial ecology (QIIME) was used to determine operational taxonomic units (OTUs) which corresponded to the 16S rRNA gene sequences. Results Leptotrichiaceae, Mycoplasma, Pasteurellaceae, and Fusobacterium were the most abundant OTUs identified in the lungs and lymph nodes of the calves which died from BRD. Leptotrichiaceae, Fusobacterium, Mycoplasma, Trueperella and Bacteroides had greater relative abundances in post-mortem lung samples collected from fatal cases of BRD in dairy calves, compared with clinically healthy calves without lung lesions. Leptotrichiaceae, Mycoplasma and Pasteurellaceae showed higher relative abundances in post-mortem lymph node samples collected from fatal cases of BRD in dairy calves, compared with clinically healthy calves without lung lesions. Two Leptotrichiaceae sequence contigs were subsequently assembled from bacterial DNA-enriched shotgun sequences. Conclusions The microbiomes of the cranial lung lobe and mediastinal lymph node from calves which died from BRD and from clinically healthy H-F calves have been characterised. Contigs corresponding to the abundant Leptotrichiaceae OTU were sequenced and found not to be identical to any known bacterial genus. This suggests that we have identified a novel bacterial species associated with BRD.
    • Baled Silage - Development Of Reliable Baled Silage Systems

      O'Kiely, Padraig; Forristal, Dermot; Lenehan, J.J. (Teagasc, 1999-05-01)
      Baled silage is now made on two-thirds of all farms in Ireland, and accounts for one third of all silage made. It is particularly prevalent as the primary silage-making system on both beef farms and smaller-sized farms. However, it is also widespread as a second silage-making system on many other farms. The series of experiments contained in this report were conducted as part of a collaborative EU Structural Funds supported research project jointly carried out between the Teagasc research centres at Grange and Oak Park. Some of the research was also conducted in collaboration with the Botany Dept. at University College Dublin.
    • Maize silage for milk production - Part 2: Effect of concentrate quality and quantity fed withmaize silage based forages on milk production

      Fitzgerald, J.J.; Murphy, J.J.; Culleton, N. (Teagasc, 1998-11-01)
      In some of the studies outlined in Part 1 of this report, mixed forages containing grass silage and a high proportion (60%) of maize silages varying in maturity and starch content were supplemented with concentrates at different levels to compare the response in milk production with a maize silage based forage and with good quality grass silage as the sole forage. The most suitable type of energy ingredient in the concentrate, i.e. high starch or low starch, high fibre ingredients, as supplements to maize silage based forages or grass silage was investigated. A range of levels of crude protein in the concentrate were examined in one study to determine the optimum level of crude protein in the supplement for maize silage based forages compared with grass silage.
    • Maize silage for milk production - Part 1: Effect of the quality of maize silage on milk

      Fitzgerald, J.J.; Murphy, J.J.; O'Mara, Frank P.; Culleton, Noel (Teagasc, 1998-11-01)
      Ensiled forage maize is an alternative or complementary forage to grass silage and is the main source of forage for ruminant livestock in many European countries. The growing of maize for silage was tried unsuccessfully in Ireland in the 1970’s, was resumed in the late 1980’s and is now well established in suitable areas in the south and east of Ireland. However, variation in growing conditions and summer radiation can result in considerable variation in the yield, maturity and feeding value of the crop from year to year and between regions or locations within years. A series of experiments were conducted at Moorepark and at Johnstown Castle Research Centre to evaluate the role of maize silage in the diet of lactating dairy cows, the effect of variation in the quality (starch content and digestibility) of maize silage, the proportion of maize silage in the forage and the effect of harvesting date of immature maize silage on feed intake, milk production and milk composition compared with an all grass silage based diet. Grass silages of moderate or high digestibility were used. These studies were carried out with cows in early or mid lactation or at both stages of lactation. The forages were supplemented with concentrates at low to moderate levels of feeding (4-7 kg/cow/day). The concentrates generally contained a high level of crude protein (220- 250 g CP/kg fresh weight) to balance the low level of crude protein in maize silage. The experiments were conducted over periods of 7-9 weeks.
    • Effect of grazing management on the maintenance of white clover

      Nolan, T.; Grennan, E.J. (Teagasc, 1998-11-01)
      The objectives of the project were to compare different cultivar types and methods to establish and maintain them in reseeded and permanent pastures as a basis for efficient low cost sheep production. In Ireland only 3% of pastures are reseeded annually and permanent pastures rarely contain more than 5% white clover. Improved clover content offers benefits of higher lamb growth rate and reduced fertiliser N use. Comparisons under cutting conditions provided no basis for replacement of Grasslands Huia by the new cultivar Aberherald. Grasslands Huia established successfully following direct reseeding and rotational grazing by sheep. It established more quickly than Kentish and gave higher yield only in the first year. A mixture of small and medium size white clovers should be sown for sheep grazing. Increasing seeding rate from 2 to 4 kg per ha increased pasture clover content only in the first year. Grasslands Huia persisted quite well for up to 5 years under rotational sheep grazing. It also survived under continuous grazing but leaf size was reduced. Rotational grazing management with sheep increased the clover content of permanent pasture from under 2% to 4% over 2 years. Highest clover yields were achieved with rest intervals of 20 to 28 days. Simulated mixed sheep and cattle rotational grazing on permanent pasture resulted in intermediate (10 to 12%) clover dry matter contributions to total dry matter compared with cattle (15 to 18%) and sheep (5 to 8%). Lamb growth rate was about 35% higher when the clover content of the sward was increased from very low to about 35%.
    • A comparison of Charolais and beef X Friesian suckler cows.

      Drennan, Michael J.; Fallon, Richard J. (Teagasc, 1998-10-01)
      The studies carried out included comparisons of Charolais and Beef x Friesian suckler cows in terms of voluntary silage intake, colostrum yield and immunoglobulin level, calf immunoglobulin level and cow milk yield in addition to animal production experiments. In all experiments the Charolais animals used were a minimum of 7/8 Charolais and were the result of an upgrading programme at Grange commencing with Charolais x Friesians. In the production experiments, only Hereford x Friesian cows (and their progeny) were compared with the Charolais while in all other experiments the Beef x Friesians included both Hereford x Friesians and Limousin x Friesians.
    • Reducing the seasonality of prime lamb production

      Grennan, E.J. (Teagasc, 1998-10-01)
      Lambing part of the national lowland flock in April to late May has potential to reduce the seasonality of supply and extend the season for prime young lamb. This would, potentially, enhance ability to maintain and increase market share for Irish lamb. A farmlet system was operated over two years, with some 50 ewes on 4 ha of pasture. The objectives were: to assess the overall performance of a flock lambing in mid to late April : to monitor lamb growth rate and drafting patterns for lambs; to determine the changes in feed demand over the season; to identify any saving in feed costs, and any difficulties that may arise with late lambing. The feed demand over the grazing season differs from normal March lambing. A grass surplus tends to occur in April/May and a deficit in November/December, and this imbalance between supply and demand increases if lambing is in late May. The balance between feed demand and supply may be more easily achieved where sheep are combined with cattle or tillage. Results show that a late-lambing flock can be managed successfully on an all-grass farm. If lambing takes place from mid-April to late May, some lambs will finish off pasture in September/October. Remainder can be finished indoor on silage with concentrate supplementation for sale in October to February. Lambing from mid-April onwards allows ewes to be at pasture for 4 to 6 weeks pre-lambing and concentrate feeding to ewes pre or post lambing should not be necessary. However this saving on concentrate input is offset by the need for concentrates to finish lambs. Lamb growth rate on pasture to weaning will be somewhat lower than with March lambing, due to deterioration in pasture digestibility in mid-season. A high standard of grassland management is critical to maintain pastures leafy, in order to achieve high lamb growth rate pre and post weaning. Profitability will depend on supplying niche markets with younger lambs at premium prices.