Environmental impact of replacing soybean meal with rapeseed meal in diets of finishing pigs

The major impact of the livestock sector on the environment may be reduced by feeding agricultural co-products to animals. Since the last decade, co-products from biodiesel production, such as rapeseed meal (RSM), became increasingly available in Europe. Consequently, an increase in RSM content in livestock diets was observed at the expense of soybean meal (SBM) content. Cultivation of SBM is associated with high environmental impacts, especially when emissions related to land use change (LUC) are included. This study aims to assess the environmental impact of replacing SBM with RSM in finishing pig diets. As RSM has a lower nutritional value, we assessed the environmental impact of replacing SBM with RSM using scenarios that differed in handling changes in nutritional level. Scenario 1 (S1) was the basic scenario containing SBM. In scenario 2 (S2), RSM replaced SBM based on CP content, resulting in reduced energy and amino acid content, and hence an increased feed intake to realize the same growth rate. The diet of scenario 3 (S3) was identical to S2; however, we assumed that pigs were not able to increase their feed intake, leading to reduced growth performance. In scenario 4 (S4), the energy and amino acid content were increased to the same level of S1. Pig performances were simulated using a growth model. We analyzed the environmental impact of each scenario using life-cycle assessment, including processes of feed production, manure management, piglet production, enteric fermentation and housing. Results show that, expressed as per kg of BW, replacing SBM with RSM in finishing pig diets marginally decreased global warming potential (GWP) and energy use (EU) but decreased land use (LU) up to 12%. Between scenarios, S3 had the maximum potential to reduce the environmental impact, due to a lower impact per kg of feed and an increased body protein-to-lipid ratio of the pigs, resulting in a better feed conversion ratio. Optimization of the body protein-to-lipid ratio, therefore, might result in a reduced environmental impact of pig production. Furthermore, the impact of replacing SBM with RSM changed only marginally when emissions related to direct (up to 2.9%) and indirect LUC (up to 2.5%) were included. When we evaluated environmental impacts of feed production only, which implies excluding other processes along the chain as is generally found in the literature, GWP decreased up to 10%, including LUC, EU up to 5% and LU up to 16%.     

Effects of atherogenic diet on young farm pigs.

This study was designed to assess the usefulness of young farm pigs as an experimental model for hypercholesterolemia. In order to test this, we investigated both serologic and electrocardiographic effects of atherogenic diet. Four-week-old pigs were fed an atherogenic diet for 8 weeks. No arrhythmia was observed on ECG in all animals. There were no significant difference between control and atherogenic diet group on the values of ECG parameters. However, plasma lipids values of atherogenic diet group were significantly (p less than 0.05) higher than those of control diet group. Thus, hypercholesterolemia was induced in young farm pigs by feeding atherogenic diet in a relatively short time. This fact suggests that young farm pigs may be an useful model for further studies of the effect of hypercholesterolemia on cardiovascular function and the early pathogenesis of atherosclerosis.     

Ecology and transmission of Listeria monocytogenes infecting ruminants and in the farm environment

A case-control study involving 24 case farms with at least one recent case of listeriosis and 28 matched control farms with no listeriosis cases was conducted to probe the transmission and ecology of Listeria monocytogenes on farms. A total of 528 fecal, 516 feed, and 1,012 environmental soil and water samples were cultured for L. monocytogenes. While the overall prevalence of L. monocytogenes in cattle case farms (24.4%) was similar to that in control farms (20.2%), small-ruminant (goat and sheep) farms showed a significantly (P < 0.0001) higher prevalence in case farms (32.9%) than in control farms (5.9%). EcoRI ribotyping of clinical (n = 17) and farm (n = 414) isolates differentiated 51 ribotypes. L. monocytogenes ribotypes isolated from clinical cases and fecal samples were more frequent in environmental than in feed samples, indicating that infected animals may contribute to L. monocytogenes dispersal into the farm environment. Ribotype DUP-1038B was significantly (P < 0.05) associated with fecal samples compared with farm environment and animal feedstuff samples. Ribotype DUP-1045A was significantly (P < 0.05) associated with soil compared to feces and with control farms compared to case farms. Our data indicate that (i) the epidemiology and transmission of L. monocytogenes differ between small-ruminant and cattle farms; (ii) cattle contribute to amplification and dispersal of L. monocytogenes into the farm environment, (iii) the bovine farm ecosystem maintains a high prevalence of L. monocytogenes, including subtypes linked to human listeriosis cases and outbreaks, and (iv) L. monocytogenes subtypes may differ in their abilities to infect animals and to survive in farm environments.     

Influence of dietary fibre on nutrient digestibility and energy utilisation in growing pigs fed diets varying in soluble and insoluble fibres from co-products

The co-products from the industry are used to reduce costs in pig diets. However, the co-products used in pig diets are limited because of a high fibre content which is not digested by endogenous enzymes and is resistant to degradation in the small and large intestines. The aim of this study was to investigate digestibility of nutrients and energy, and energy utilisation in pigs fed diets with various soluble and insoluble dietary fibre (DF) from co-products. The experiment was performed as a 4 × 4 Latin square design (four diets and four periods) using four growing pigs (66.2 ± 7.8 kg) surgically fitted with a T-cannula in the end of the small intestine. The pigs were fed four experimental diets: low-fibre control (LF), high-fibre control (HF), high-soluble fibre (HFS) and high-insoluble fibre (HFI) diets. The apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of ash, organic matter, CP, fat, carbohydrates, starch and non-starch polysaccharides (NSP) divided into cellulose and soluble and insoluble non-cellulosic polysaccharide residues were measured using chromic oxide as marker. The recovery of total solid materials, organic matter and total carbohydrates in ileal digesta in pigs fed the HF and HFS diets was higher than in pigs fed LF and HFI, whereas recovery of organic matter and total carbohydrates in faecal materials in the HFS diet was lowest (P < 0.05). AID of organic matter, total carbohydrates and starch was lowest for HFS diet (P < 0.05). ATTD of organic matter and CP was higher for LF diet compared with other diets (P < 0.05), whereas total NSP, cellulose and non-cellulosic polysaccharides residues were highest for HFS diet (P < 0.05). Lactic acid in ileal digesta was influenced by dietary composition (P < 0.05) whereas neither type nor level of DF affected short chain fatty acids. The digestible energy, metabolisable energy, net energy and retained energy intake were similar among diets without influence of DF inclusion (P > 0.05). The metabolisable energy:digestible energy ratio was lower when feeding the HFS diet because of a higher fermentative methane loss. Faecal nitrogen and carbon were positively correlated with DM intake and insoluble DF in the diets (P < 0.05), but nitrogen and carbon (% of intake) were similar among diets. The present findings suggest that high-DF co-products can be used as ingredients of pig diets when features of DF are considered.     

Pig carcass tail lesions: the influence of record keeping through an advisory service and the relationship with farm performance parameters

Tail lesions are important pig welfare indicators that could be recorded during meat inspection as they are more visible on the carcass than on the live animal. Tail biting is associated with reduced performance in the bitten pig, but it is not clear whether problems with tail biting are reflected in general farm performance figures. Farm advisory services aim to improve farm productivity which could be associated with improvements in pig welfare. Record keeping forms an integral part of such advisory services. The aim of this study was to examine the influence of record keeping in the Teagasc eProfit Monitor (ePM herds) on the prevalence of tail lesion severity scores in Irish slaughter pigs. In addition, we investigated associations between the prevalence of tail lesion scores and production parameters at farm level in ePM herds. Pigs were observed after scalding/dehairing and tail lesion score (0 to 4), sex and farm identification were recorded. Tail lesion scores were collapsed into none/mild lesions (score ⩽1), moderate lesions (score 2) and severe lesions (score ⩾3). The effect of record keeping (ePM herd) on the different tail lesion outcomes was analysed at batch level using the events/trials structure in generalized linear mixed models (PROC GLIMMIX). Spearman’s rank correlations were calculated between average tail lesion score of a batch and production parameters. A total of 13 133 pigs were assessed from 73 batches coming from 61 farms. In all, 23 farms were identified as ePM herds. The average prevalence of moderate tail lesions was 26.8% and of severe tail lesions was 3.4% in a batch. Batches coming from ePM herds had a lower prevalence of moderate tail lesions than non-ePM herds (P<0.001). Average tail lesion score was negatively associated with age (P<0.05) and weight (P<0.05) at sale/transfer of weaners, and tended to be positively associated with the number of finishing days (P=0.06). In addition, the prevalence of severe tail lesions was negatively associated with average daily gain in weaners (P<0.05) and tended to do so with average daily gain in finishers (P=0.08). This study provides the first indication that record keeping through an advisory service may help to lower the risk of tail biting, which is associated with improved farm performance.     

Bacterial genome sequencing tracks the housefly-associated dispersal of fluoroquinolone- and cephalosporin-resistant Escherichia coli from a pig farm

The regular use of antimicrobials in livestock production selects for antimicrobial resistance. The potential impact of this practice on human health needs to be studied in more detail, including the role of the environment for the persistence and transmission of antimicrobial-resistant bacteria. During an investigation of a pig farm and its surroundings in Brandenburg, Germany, we detected abundant cephalosporin- and fluoroquinolone-resistant Escherichia coli in pig faeces, sedimented dust, and house flies (Musca domestica). Genome sequencing of E. coli isolates revealed large phylogenetic diversity and plasmid-borne extended-spectrum beta lactamase (ESBL) genes CTX-M-1 in multiple strains. [Correction added on 28 February 2023, after first online publication: In the preceding sentence, ‘and TEM-1’ was previously included but has been deleted in this version.] Close genomic relationships indicated frequent transmission of antimicrobial-resistant E. coli between pigs from different herds and across buildings of the farm and suggested dust and flies as vectors for dissemination of faecal pathogens. Strikingly, we repeatedly recovered E. coli from flies collected up to 2 km away from the source, whose genome sequences were identical or closely related to those from pig faeces isolates, indicating the fly-associated transport of diverse ESBL-producing E. coli from the pig farm into urban habitation areas. The observed proximity of contaminated flies to human households poses a risk of transmission of antimicrobial-resistant enteric pathogens from livestock to man.     

Sustainability assessment of salmonid feed using energy,classical exergy and eco-exergy analysis

Reduction of the environmental impact of feed products is of paramount importance for salmon farming. This article explores the potential to compare three thermodynamically based ecological indicators. The environmental impact of partial replacement of fish meal (FM) and fish oil with alternative ingredients was investigated using energy, classical exergy and eco-exergy analysis. Seven hypothetical feeds were formulated: one with high levels of FM and fish oil, four feeds based on plant ingredients, one containing krill meal, and one based on algae-derived products. Analysis included cultivation of crops and algae, fishing for fish and krill, industrial processing of these ingredients and production of complete fish feed. Because most harvested products are refined in multiple product outputs that have good value to society, two scenarios were compared. In the base case scenario, no allocation of co-products was used and all the environmental costs were ascribed to one specific co-product. Co-product allocation by mass was used in the second scenario; this is considered to be the preferred scenario because it accurately reflects the individual contributions of the co-products to the environmental impact of the feed products. For this scenario, the total energy consumption for a fish-based diet was 14,500 MJ, which was similar to a krill diet (15,600 MJ), about 15–31% higher than plant-based diets, and 9% higher than an algae diet. Substituting FM and fish oil with alternative ingredients resulted in minor changes in total classical exergy degradation (2–16% difference). The calculations based on energy only consider the energy conservation based on the First Law of Thermodynamics, whereas those based on classical exergy also takes the Second Law of Thermodynamics into account; energy that can do work is distinguished from energy that is lost as heat to the environment. The calculations based on eco-exergy consider the total loss of work energy in the environment including the work energy associated with the information embodied in the genomes of organisms. The diet based on fishery-derived ingredients was the highest total work energy consumer compared with plant-based diets (24–30% greater), the diet containing krill meal (25% greater), and the algae diet (four times higher). Thus, reducing FM and fish oil levels in fish feed can contribute significantly to more sustainable aquaculture. In particular, algae-derived products in aquafeeds could drastically decrease environmental costs in the future.     

Danish free-ranging mink populations consist mainly of farm animals: Evidence from microsatellite and stable isotope analyses

Two methods were used to separate free-ranging mink Mustela vison into wild mink and escaped farm mink. Analysis of stable carbon isotopes was performed on teeth and claws of 226 free-ranging mink from two areas in Denmark. A classification based on empirical data resulted in three groups (n=213); 47% were newly escaped farm mink and another 31% had been born in farms and lived in nature for more than ca. 2 months. The remaining 21% may or may not have been born in nature, but they had been free ranging for more than a year and were thus considered wild. A genetic analysis by means of microsatellites was performed on a subsample of the trapped mink (86 individuals) and on 70 farm mink, in order to assess the proportion of escaped farm mink in the free-ranging population. Strong genetic evidence for a high percentage of escaped farm mink in the free-ranging population (86%) was found, in agreement with the carbon isotope results. Both methods can be used to distinguish between farm and wild mink, but whereas microsatellites can only say whether a given mink originated from a farm or not, carbon isotopes can give some more detail on the period of time that a farm mink has been living in natural habitats. The high proportion of escaped farm mink in the Danish nature could have serious implications for the preservation of other vulnerable species and should be carefully considered when designing conservation strategies.     

Analysis of the mitochondrial haplogroups of farm and wild-living raccoon dogs in Poland

Raccoon dogs' mitochondrial DNA genes (MT-CYTB, MT-CO1 and MT-CO2) containing a total of 1.5?kbp exhibited 11 synonymous substitutions in the polymorphism described, with almost 73% found in the gene MT-CO2. The polymorphism was observed in 27.3% of the loci in wild-living animals, and in over 90% of the loci in farm raccoon dogs. Seven mitochondrial haplogroups have been determined, among which three (Np1, Np2 and Np4) were found in the wild-living raccoon dogs and the other four (Np3, Np5, Np6 and Np7) in the farm animals. The occurrence of new haplogroups in the farm animals indicates the appearance of adaptive mutations. Differences were observed between the sequence under study and the reference sequence in MT-CYTB; they involved two non-synonymous substitutions (T304I and F332L). Analyses carried out to determine the deleterious effect of mutations indicated an almost 50% probability that a single amino acid substitution (T304I) in the protein has a negative impact on its function.     

Entire male pigs in farrow-to-finish pens—Effects on animal welfare

Aggressive and sexual behaviour can hamper animal welfare in entire male pig production. The aim of the present study was to investigate if rearing entire male pigs in sibling groups (in farrow-to-finish pens) could reduce aggressive and sexual behaviour and thereby improve animal welfare in entire male pig production. Frequencies of aggressive and sexual behaviour among finishing pigs were recorded in three different groups in one herd; FTF-group (entires + gilts, siblings), mix-group (entires + gilts, mixed) and castrate-group (castrates + gilts, siblings). Frequencies of skin wounds were recorded in this herd and in an additional herd (only FTF-group and mix-group) shortly before the animals were sent to slaughter. Higher skin lesion scores in the entire male pig groups were in accordance with the behaviour data. Rearing entire male pigs in sibling groups reduces aggressive behaviour, though the frequency of the aggressive behaviour bouts was still higher than it was in the castrate-group. The frequency of skin wounds in the FTF-group was reduced to similar levels as in the castrate-group. The findings suggest that rearing entire males in sibling groups may be an appropriate management strategy for improving animal welfare in entire male pig production.     

Agricultural intensification in a Philippine frontier community: Impact on labor efficiency and farm diversity

There continues to be much debate in anthropology concerning the mechanism by which agricultural intensification takes place and its impact on labor efficiency, farm diversity, and quality of diet. A major reason for this lack of consensus is the paucity of data from case studies that focus on specific agricultural systems at the point of transition from extensive to intensive methods of cultivation. Research in a frontier community in the Philippines, where farmers are making the shift from swidden cultivation to small-scale irrigated rice production, indicates that intensification does not necessarily result in lower efficiency or a decline in dietary standards. Rather, farmers faced with growing population pressure and an unproductive short fallow swidden system have been motivated to adopt irrigation because it increases the efficiency of their labor while maintaining a reliable and diverse farming system.     

Modelling batch farrowing management within a farrow-to-finish pig herd: influence of management on contact structure and pig delivery to the slaughterhouse

Pathogen spread within pig host populations can vary depending on within-herd interactions among pigs also called the contact structure. The recommended batch farrowing management, allowing for a fixed-interval mating for groups of sows of equal size, called batches, leads to an all-in/all-out management of pigs in which animals in different batches have no contact. To maintain a profitable pig delivery, producers have to deliver groups of pigs at a given weight, what needs sometimes herd management adaptations. However, producers’ adaptations that avoid delivering pigs below slaughtering weight (out-of-range pigs), result in increasing the contact between animals from different batches. To study the influence of herd management on contact structure and on pig delivery, a stochastic mathematical model representing population dynamics within a farrow-to-finish herd was elaborated. Sixteen management systems were represented combining or not the all-in/all-out management system with producers’ decisions: batch mixing, use of an extra room, suppression of the drying period and sale of post-weaning batches. Two types of contact were considered: via the animals themselves, when batch mixing occurred; and via the room, when decontamination was not complete. The impact of producers’ decisions on contact structure and on pig delivery, differed radically when pig growth was normal and when it was slow (i.e. mean age at slaughtering weight increased by 20%). When pig growth was normal, the all-in/all-out management prevented both contact via the animals and via the room but resulted in 9% of pigs delivered out of range. The use of an extra room or batch mixing decreased this percentage, the latter resulting in very frequent contact between batches via the animals. When pig growth was slow, the all-in/all-out management led to a very high percentage of pigs delivered out of range (almost 80%). The suppression of the drying period at the end of the finishing period and the sale of post-weaning batches induced a significant decrease in this percentage (down to 2% to 20%), the latter allowing to reduce the percentage of batches that made contact via the room (40% instead of 80%). This pig herd model helped to understand the compromise for producers between implementing internal biosecurity or maintaining a profitable pig delivery. Our results show that there was no unique optimal system and that efficient producers’ decisions (for biosecurity and delivery) may differ, depending on pig growth.     

Social life cycle assessment of average Irish dairy farm

Purpose

The majority of sustainability studies of dairy farms focused on environmental performance and profitability; however, social aspect has been hardly assessed. This study aims to investigate the social impacts of dairy farm via a case study using a social life cycle assessment framework.

Methods

The assessment was carried out applying the social LCA Guideline by UNEP-SETAC. Nineteen suitable social indicators were selected from four stakeholder categories of the guideline. Characterization and normalization were further developed based on data availability. National farm survey data was used as foreground data for farm activities, supplemented with background data from public database and life cycle working environment (LCWE) data by Gabi database. All indicators were divided into three groups: functional unit-related quantitative indicators, non-functional unit-related quantitative indicators and semi-quantitative indicators.

Results and discussion

Irish dairy farming has positive social impacts on value chain actors and society, predominantly positive impacts for local community and generally positive values for workers. The main negative impacts are health and safety issue, equal opportunity for workers, and safe and healthy living conditions for the local community. Possible actions to improve the social performance include introducing more efficient and robotic milk production systems; applying better handling methods and using real time decision support to operational management for emissions reduction.

Conclusions

This study is the first attempt of social LCA in Ireland. It demonstrated a possible method to carry out SLCA for Irish dairy sector. The results identified the positive and negative social hotspot of dairy farm with recommendation for future improvement.

     

MicroRNAs in farm animals

MicroRNAs (miRNAs) are a class of ∼22 nucleotide-long small noncoding RNAs that target mRNAs for translational repression or degradation. miRNAs target mRNAs by base-pairing with the 3′-untranslated regions (3′-UTRs) of mRNAs. miRNAs are present in various species, from animals to plants. In this review, we summarize the identification, expression, and function of miRNAs in four important farm animal species: cattle, chicken, pig and sheep. In each of these species, hundreds of miRNAs have been identified through homology search, small RNA cloning and next generation sequencing. Real-time RT-PCR and microarray experiments reveal that many miRNAs are expressed in a tissue-specific or spatiotemporal-specific manner in farm animals. Limited functional studies suggest that miRNAs have important roles in muscle development and hypertrophy, adipose tissue growth, oocyte maturation and early embryonic development in farm animals. Increasing evidence suggests that single-nucleotide polymorphisms in miRNA target sites or miRNA gene promoters may contribute to variation in production or health traits in farm animals.     

东莞桥头镇农业生态系统模式的研究

为探索东莞市桥头镇的农业现代化,运用面上调查和定点分析的研究方法,概括了全镇现有的４大类农业生态系统模式,对其进行了能流和磷流分析,得到如下结果：规模经营的综合种养场水稻产出较高,纯收益较好,光能利用和辅助能能效较高,而传统小规模水稻则有机肥投入比例大,磷效高;单－蔬菜种植模式的菜场,干物产量低,光能利用率和辅能能效低,磷素投入高,但有机磷比例低,故磷效低,但经济效益好。综合种养场猪和鱼的养殖,生产成本低,经济效益好,养猪和鱼分别可将生活废弃物中３９．６２％和１２．６８％的磷转化为产品磷。农科园集约化鸡场能量产投比低,但对全价饲料中磷素的转化率高达６２．６５％。本文还就该镇在新的经济环境下,调整农业布局、采纳王高农业模式方面展开了论述。     

Modelling environmentally mediated spread of livestock-associated methicillin-resistant Staphylococcus aureus in a pig herd

Infectious disease models are a useful tool to support within-herd disease control strategies. This study presents a stochastic compartment model with environmentally mediated transmission to represent the spread of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) in a farrow-to-finish pig herd. The aims of the study were to (1) construct a model of the spread of LA-MRSA that included spread of LA-MRSA through the environment; (2) parameterise the model to fit previously published observational data in order to obtain realistic LA-MRSA transmission rates; (3) and to investigate how changes in the mixing of animals in the farrowing and finishing units may affect the prevalence of LA-MRSA in a herd. The results showed that indirect transmission allowed LA-MRSA to persist in the herd without the assumption of persistently shedding individuals. Reducing the mixing of pigs upon entry to the finishing unit was also shown to lower the LA-MRSA prevalence in the unit if the initial LA-MRSA level in the unit was low, but at high prevalence, no effect of mixing was identified. In the farrowing unit, changing the proportion of piglets that were cross-fostered did not affect the within-herd LA-MRSA prevalence. The study demonstrates that there are several important knowledge gaps regarding the shedding and transmission of LA-MRSA in different animal age groups and further experimental studies are needed. This work also provides a new, robust and flexible model framework for the investigation of control and mitigation strategies for LA-MRSA and other infections in a pig herd.     

Effect of biofuel co-products in pig diets on the excretory patterns of N and C and on the subsequent ammonia and methane emissions from pig effluent

This study was conducted to investigate the effects of incorporation into pig diets of 20% of different co-products from the biofuel industries, which are rich in fibre, on animal growth performance, on nitrogen (N) and carbon (C) excretions, and on the subsequent ammonia volatilisation and methane production during the storage of slurry. Five experimental diets mainly based on wheat and soyabean meal were formulated: two control diets, a control high-protein (CHP) diet with 17.5% of crude protein (CP) and a control low-protein (CLP) diet with 14.0% of CP and three experimental diets with 20% of (i) dried distiller's grain with solubles (DDGS), (ii) sugar beet pulp (SBP) or (iii) fatty rapeseed meal (FRM). The animals used (20 castrated males) were housed individually in metabolism cages and fed one of the five diets (i.e. four pigs per diet). Urine and faeces were collected separately from each pig in order to measure nutrient digestibility and the excretory patterns of N and C. For each diet, ammonia volatilisation was measured from samples of slurry subsequently produced, over a 16-day storage period in a laboratory pilot scale system. The ultimate methane potential (B0, expressed in litres CH4/kg organic matter (OM)) was measured from the same slurry, for each diet, in anaerobic storage conditions over 100 days. The addition of sources of fibres to the diet decreased (P < 0.05) the animal growth performance by 13% and increased (P < 0.05) the amount of faeces excreted by 100%, whereas the amount of urine was not affected. For the high-fibre diets, there was a shift of N partitioning from urine to faeces, resulting in a much higher faecal N excretion (10 v. 5 g N/pig per day). Concurrently, the fibre enrichment in diets significantly increased (P < 0.05) the C content of the faeces by 68%. Ammonia emission from slurry was significantly reduced (P < 0.05) by 19% to 33% for the high-fibre diets, compared to the CHP diet. Ammonia emission was also reduced (P < 0.05) by 33% for the CLP compared to the CHP diet. B0 values ranged from 428 to 484 l CH4/kg OM. When these are expressed per pig and per day, the B0 from slurry was, on average, 70 l for the two control diets, and 121, 91 and 130 l for the slurry originating from the DDGS, SBP and FRM diets, respectively.     

Farm‐by‐farm analysis of microsatellite,mtDNA and SNP genotype data reveals inbreeding and crossbreeding as threats to the survival of a native Spanish pig breed

The Chato Murciano (CM), a pig breed from the Murcia region in the southeastern region of Spain, is a good model for endangered livestock populations. The remaining populations are bred on approximately 15 small farms, and no herdbook exists. To assess the genetic threats to the integrity and survival of the CM breed, and to aid in designing a conservation program, three genetic marker systems – microsatellites, SNPs and mtDNA – were applied across the majority of the total breeding stock. In addition, mtDNA and SNPs were genotyped in breeds that likely contributed genetically to the current CM gene pool. The analyses revealed the levels of genetic diversity within the range of other European local breeds (H_e = 0.53). However, when the eight farms that rear at least 10 CM pigs were independently analyzed, high levels of inbreeding were found in some. Despite the evidence for recent crossbreeding with commercial breeds on a few farms, the entire breeding stock remains readily identifiable as CM, facilitating the design of traceability assays. The genetic management of the breed is consistent with farm size, farm owner and presence of other pig breeds on the farm, demonstrating the highly ad hoc nature of current CM breeding. The results of genetic diversity and substructure of the entire breed, as well as admixture and crossbreeding obtained in the present study, provide a benchmark to develop future conservation strategies. Furthermore, this study demonstrates that identifying farm‐based practices and farm‐based breeding stocks can aid in the design of a sustainable breeding program for minority breeds.     

Environmental impacts of precision feeding programs applied in pig production

This study was undertaken to evaluate the effect that switching from conventional to precision feeding systems during the growing-finishing phase would have on the potential environmental impact of Brazilian pig production. Standard life-cycle assessment procedures were used, with a cradle-to-farm gate boundary. The inputs and outputs of each interface of the life cycle (production of feed ingredients, processing in the feed industry, transportation and animal rearing) were organized in a model. Grain production was independently characterized in the Central-West and South regions of Brazil, whereas the pigs were raised in the South region. Three feeding programs were applied for growing-finishing pigs: conventional phase feeding by group (CON); precision daily feeding by group (PFG) (whole herd fed the same daily adjusted diet); and precision daily feeding by individual (PFI) (diets adjusted daily to match individual nutrient requirements). Raising pigs (1 t pig BW at farm gate) in South Brazil under the CON feeding program using grain cultivated in the same region led to emissions of 1840 kg of CO₂-eq, 13.1 kg of PO₄-eq and 32.2 kg of SO₂-eq. Simulations using grain from the Central-West region showed a greater climate change impact. Compared with the previous scenario, a 17% increase in climate change impact was found when simulating with soybeans produced in Central-West Brazil, whereas a 28% increase was observed when simulating with corn and soybeans from Central-West Brazil. Compared with the CON feeding program, the PFG and PFI programs reduced the potential environmental impact. Applying the PFG program mitigated the potential climate change impact and eutrophication by up to 4%, and acidification impact by up to 3% compared with the CON program. Making a further adjustment by feeding pigs according to their individual nutrient requirements mitigated the potential climate change impact by up to 6% and the potential eutrophication and acidification impact by up to 5% compared with the CON program. The greatest environmental gains associated with the adoption of precision feeding were observed when the diet combined soybeans from Central-West Brazil with corn produced in Southern Brazil. The results clearly show that precision feeding is an effective approach for improving the environmental sustainability of Brazilian pig production.     

Evaluation of the use of pooled serum, pooled muscle tissue fluid (meat juice) and pooled faeces for monitoring pig herds for Salmonella

AIMS: Monitoring for Salmonella in slaughter pigs is important to enable targeted control measures to be applied on problem farms and at the abattoir. The aim of this study was to determine whether pooled serum and meat juice could be used to identify finishing pig herds with a high prevalence of infection. METHODS AND RESULTS: Samples of meat juice, serum, caecal contents, carcase swabs and pooled faeces from pig pens were taken from 20 commercial pig finishing farms and comparisons were made between the results of Salmonella culture, individual ELISA tests on serum and meat juice and pooled samples of serum and meat juice. Salmonella was isolated from samples from 19 of 20 farms. None of the ELISA tests showed a statistically significant correlation with caecal carriage of Salmonella or contamination of carcases. Serum mean optical density (O.D.) from pools of five, 10 or 20 sera showed a significant correlation with the Salmonella status of farm pen faeces. All pooled serum O.D. and sample/positive control ratio results correlated significantly with the results of the conventional individual sample ELISA. There was a statistically significant correlation between the incidence of Salmonella in farm pen pooled faeces and the prevalence of Salmonella in caeca of slaughter pigs. CONCLUSIONS: The results show a generally poor correlation between serological and bacteriological results but pooled serum or meat juice samples could be used as a cheaper substitute for serological screening of farms for Salmonella than individual samples. SIGNIFICANCE AND IMPACT OF THE STUDY: The availability of a cheaper test should allow the costs of Salmonella monitoring of pig farms to be reduced or allow more regular testing to enhance the designation of farm Salmonella risk status.