Now showing items 21-40 of 851

    • Effect of a single, oral administration of selenitetriglycerides, at two dose rates, on blood selenium status and haematological and biochemical parameters in Holstein-Friesian calves

      Żarczyńska, Katarzyna; Sobiech, Przemysław; Tobolski, Dawid; Mee, John F; Illek, Josef; University of Warmia and Mazury; Minister of Science and Higher Education, Poland; 010/RID/2018/19 (Biomed Central, 2021-04-23)
      Background Selenitetriglycerides are biologically active, organic forms of selenium formed as a result of the modification of selenic acid and sunflower oil. Studies in rats have shown that they are well absorbed and of low toxicity. There are no published studies on selenitetriglycerides supplementation in calves. Results In this study, selenitetriglycerides were administered once orally on the 2nd day of life at a dose of 0.5 or 1 mg Se/kg body weight to each of six Holstein-Friesian calves while six control calves were not supplemented. Blood for determination of selenium concentration, glutathione peroxidase activity, haematological parameters, aspartate aminotransferase, creatine kinase, and lactate dehydrogenase activities and glucose, total protein, albumin, triglycerides, cholesterol, urea, and creatinine concentration was collected before supplementation (day 0) and 1, 2, 5, 10 and 14 days after supplementation. Selenitetriglycerides administration increased (P < 0.01) serum selenium concentration in supplemented calves as early as day1, from a mean of 63.4 to 184.22 µg/l in calves receiving selenium at a dose of 0.5 mg/kg BW, and from 63.17 to 200.33 µg/l in calves receiving 1 mg/kg. Serum selenium concentrations remained significantly higher compared to the control group throughout the experiment. Glutathione peroxidase activity was higher in supplemented than control calves, significantly so in animals receiving the 1 mg/kg dose of Se on the 10th and 14th days (P < 0.05). There were no significant differences in the haematological and biochemical parameters between the groups. Conclusions This experiment showed that supplementation with selenitetriglycerides could significantly improve blood selenium status in calves without adverse effects on haematological or biochemical parameters. These findings are essential prerequisites for future studies on selenitetriglycerides supplementation to manage clinical selenium deficiency in calves.
    • Association between clinical respiratory signs, lung lesions detected by thoracic ultrasonography and growth performance in pre‐weaned dairy calves

      Cuevas-Gómez, Inmaculada; McGee, Mark; Sánchez, José M; O’Riordan, Edward; Byrne, Nicky; McDaneld, Tara; Earley, Bernadette; US-Ireland DAFM grant; 2018US-IRL200 (Biomed Central, 2021-03-25)
      Background Bovine respiratory disease (BRD) is the main cause of mortality among 1-to-5 month old calves in Ireland, accounting for approximately one-third of deaths. Despite widespread use of clinical respiratory signs for diagnosing BRD, lung lesions are detected, using thoracic ultrasonography (TUS) or following post-mortem, in calves showing no clinical signs. This highlights the limitation of clinical respiratory signs as a method of detecting sub-clinical BRD. Using 53 purchased artificially-reared male dairy calves, the objectives of this study were to: (i) characterise the BRD incidence detected by clinical respiratory signs and/or TUS, (ii) investigate the association between clinical respiratory signs and lung lesions detected by TUS, and (iii) assess the effect of BRD on pre-weaning growth. Results Clinical BRD (based on Wisconsin clinical respiratory score and/or rectal temperature > 39.6 ºC) was detected in 43 % and sonographic changes (lung lesions) were detected in 64 % of calves from purchase (23 (SD; 6.2) days of age) until weaning, 53 days post-arrival. Calves with clinical BRD were treated. Sixty-one per cent calves affected with clinical BRD had lung lesions 10.5 days (median) before detection of clinical signs. Moderate correlations (rsp 0.70; P < 0.05) were found between cough and severe lung lesions on arrival day, and between rectal temperature > 39.6 ºC and lung lesions ≥ 2 cm2 on day 7 (rsp 0.40; P < 0.05) post-arrival. Mean average daily live weight gain (ADG) of calves from purchase to weaning was 0.75 (SD; 0.10) kg; calves with or without clinical BRD did not differ in ADG (P > 0.05), whereas ADG of those with severe lung lesions (lung lobe completely consolidated or pulmonary emphysema) was 0.12 kg/d less (P < 0.05) than calves without lung lesions. Conclusions Thoracic ultrasonography detected lung consolidation in calves that did not show signs of respiratory disease. The presence of severe lung lesions was associated with reduced pre-weaning growth. These findings emphasise the importance of using TUS in addition to clinical respiratory scoring of calves for an early and accurate detection of clinical and sub-clinical BRD.
    • Effect of space allowance and mixing on growth performance and body lesions of grower-finisher pigs in pens with a single wet-dry feeder

      Camp Montoro, Jordi; Boyle, Laura A; Solà-Oriol, David; Muns, Ramon; Gasa, Josep; Garcia Manzanilla, Edgar; Teagasc Walsh Scholarship Programme; 0415 (Biomed Central, 2021-01-06)
      Background Low space allowance (SA) and mixing may result in reduced growth performance (GP) and animal welfare issues because of adverse social behaviours directed to pen mates. This could be exacerbated in pens with single space feeders owing to social facilitation of feeding behaviour. The present study aimed to investigate the effect of SA and mixing on GP and body lesions (BL) in pens with one single space wet-dry feeder. Results Two experiments were conducted on grower-finisher pigs from 10 to 21 weeks of age. In Exp1, pigs (N = 216) were assigned to three SA; 0.96 m2/pig (n = 6 pens; 10 pigs/pen; SA96), 0.84 m2/pig (n = 6; 12 pigs/pen; SA84) and 0.72 m2/pig (n = 6; 14 pigs/pen; SA72), in a randomized design. In Exp2, pigs (N = 230) were used in a 2 × 2 factorial randomized design considering SA and mixing as treatments. Pigs were assigned to two SA; 0.96 m2/pig (n = 10 pens; 10 pigs/pen; SA96) and 0.78 m2/pig (n = 10; 13 pigs/pen; SA78) and were either mixed or not at the entry to the finishing facility. GP was not affected by SA (P > 0.05) in either experiment. In Exp2, non-mixed pigs were 5.4 kg heavier (P <  0.001), gained 74 g more per day (P = 0.004), consumed 101.8 g more of feed per day (P = 0.007) and tended to have higher feed efficiency (P = 0.079) than mixed pigs from 11 to 21 weeks of age. Number of BL was affected by SA in both experiments. In Exp1, SA72 pigs had 74.4 and 97.4% more BL than SA96 and SA84 pigs at 20 weeks of age respectively (P <  0.01). In Exp2, SA78 pigs had 48.6, 43.6 and 101.3% more BL than SA96 pigs at 12, 16 and 21 weeks of age respectively (P <  0.05). Mixing did not affect the number of BL from 12 to 21 weeks of age in Exp2 (P > 0.05). Conclusion Mixing had a considerable effect on growth performance thus, strategies to avoid or mitigate mixing should be considered. Although space allowance had no effect on growth performance, high number of body lesions in the lower space allowance indicates that space allowances equal or below 0.78 m2/pig are detrimental to the welfare of pigs despite following the EU legislation.
    • Identifying challenges to manage body weight variation in pig farms implementing all-in-all-out management practices and their possible implications for animal health: a case study

      Rodrigues da Costa, Maria; García Manzanilla, Edgar; Diana, Alessia; van Staaveren, Nienke; Torres-Pitarch, Alberto; Boyle, Laura A; Calderón Díaz, Julia A; Department of Agriculture, Food and the Marine; Teagasc Walsh Fellowship Programme; 14/S/832; et al. (Biomed Central, 2021-01-11)
      Background Managing body weight (BW) variation is a challenge in farrow-to-finish farms implementing all-in/all-out (AIAO) production systems due to the lack of “off-site” facilities to segregate slow growing pigs (SGP). This case study investigated different approaches to managing BW variation in a farrow-to-finish commercial pig farm with a self-declared AIAO management and the possible implications for animal health. Case presentation A total of 1096 pigs (1047 pigs born within 1 week plus 49 pigs born 1 week later) were tracked until slaughter as they moved through the production stages. Piglets were individually tagged at birth and their location on the farm was recorded on a weekly basis. In total, 10.3% of pigs died during lactation. Four main cohorts of pigs were created at weaning and retrospectively identified: cohort 1 = pigs weaned at 21 days (4.5%); cohort 2 = pigs weaned at 28 days (81.0%), which was sub-divided at the end of the first nursery stage into sub-cohort 2a = pigs split at 3 weeks post-weaning (29.7%); sub-cohort 2b = pigs split at 3 weeks post-weaning from cohort 2a and split again 5 weeks post-weaning (35.5%) and sub-cohort 2c = remaining smaller size pigs from cohort 2b (10.9%); cohort 3 = pigs weaned at 35 days (2.7%) and cohort 4 = pigs weaned at 49 days (1.5%) that were later mixed with SPG, delayed pigs from other cohorts and sick/injured pigs that recovered. Four strategies to manage BW variation were identified: i) earlier weaning (cohort 1); ii) delayed weaning of SGP (cohort 3 and 4); iii) re-grading pens by BW (sub-cohorts 2a, 2b and 2c) and, iv) delayed movement of SGP to the next production stage (several pigs from all cohorts). A higher percentage of delayed pigs presented pericarditis, pleurisy and enzootic pneumonia like lesions at slaughter compared with pigs under other strategies. Conclusion A variety of management practices were implemented to minimise BW variation during the production cycle. However, several cohorts of pigs were created disrupting AIAO management. Earlier weaning should only be practiced under specific circumstances where optimal animal health and welfare are guaranteed. Delayed weaning of SGP and delaying pigs to move to the next production stage could negatively affect animal health and should be avoided.
    • Investigation of bovine abortion and stillbirth/perinatal mortality - similar diagnostic challenges, different approaches

      Mee, John F (Biomed Central, 2020-09-04)
      Abstract This pracademic paper reviews current bovine foetopathy (abortion and stillbirth) case definitions, reporting and triage, and causes and time-of-death and proposes veterinary practitioner-focused investigative standard operating procedures (SOPs). Issues of under- and over-triage and intra-institutional SOP harmonisation are also discussed. It is proposed that an ‘observable abortion’ (120–260 days of gestation) is a more practitioner-friendly definition of abortion for reporting and benchmarking purposes and that the term ‘peristillbirth’ can replace stillbirth and perinatal mortality. Diagnosis of bovine foetopathy involves an investigative triad of the farmer, veterinary practitioner and the veterinary diagnostic laboratory. However, the poor sensitivity of abortion reporting undermines the value of currently adopted scanning/passive surveillance; parallel active surveillance/sentinel herd models should also be employed. The approach to abortion investigation differs from that of peristillbirth. The former should include collecting a herd and case history, examination and sampling of dam and cohorts and sampling of the foetus and placenta. A sample selection decision tree is provided to assist test selection. In peristillbirths, non-infectious and periparturient causes-of-death are more important hence the anamnesis must focus on peristillbirth risk factors and calving management. The foetopsy, while including the sampling menu appropriate to aborted foetuses, must also include a detailed internal and external examination of the carcass for lesions indicative of periparturient causes-of-death. In addition, for aborted foetuses the time-of-death is not important as the foetus is generally not viable; however, for the peristillbirth the time-of-death is critical as it provides useful information for the farmer to address modifiable risk factors and to alter their perinatal management. Reporting of the ultimate cause-of-death is more useful to prevent future abortions and peristillbirths though the proximate cause-of-death is often reported in the absence of a complete clinical anamnesis. Finally, the common reasons for diagnosis not reached (DNR) and the limitations of current investigative approaches are discussed.
    • Antimicrobial resistance in commensal Escherichia coli and Enterococcus spp. is influenced by production system, antimicrobial use, and biosecurity measures on Spanish pig farms

      Mencía-Ares, Oscar; Argüello, Héctor; Puente, Héctor; Gómez-García, Manuel; Manzanilla, Edgar G; Álvarez-Ordóñez, Avelino; Carvajal, Ana; Rubio, Pedro; INIA; Spanish Government (Ministerio de Educación y Formación Profesional); et al. (Biomed Central, 2021-03-19)
      Background Antimicrobial resistance (AMR) is a global public health threat consequence of antimicrobial use (AMU) in human and animal medicine. In food-producing animals factors such as management, husbandry or biosecurity may impact AMU. Organic and extensive Iberian swine productions are based on a more sustainable and eco-friendly management system, providing an excellent opportunity to evaluate how sustained differences in AMU impact the AMR in indicator bacteria. Here, we evaluate the usefulness of commensal Escherichia coli and Enterococcus spp. isolates as AMR bioindicators when comparing 37 Spanish pig farms from both intensive and organic-extensive production systems, considering the effect of AMU and biosecurity measures, the last only on intensive farms. Results The production system was the main factor contributing to explain the AMR differences in E. coli and Enterococcus spp. In both bacteria, the pansusceptible phenotype was more common (p < 0.001) on organic-extensive farms when compared to intensive herds. The microbiological resistance in commensal E. coli was, for most of the antimicrobials evaluated, significantly higher (p < 0.05) on intensive farms. In enterococci, the lincosamides usage revealed the association between AMR and AMU, with an increase in the AMR for erythromycin (p < 0.01), quinupristin-dalfopristin (p < 0.01) and the multidrug-resistant (MDR) phenotype (p < 0.05). The biosecurity measures implemented on intensive farms influenced the AMR of these bioindicators, with a slightly lower resistance to sulfamethoxazole (p < 0.01) and the MDR phenotype (p < 0.05) in E. coli isolated from farms with better cleaning and disinfection protocols. On these intensive farms, we also observed that larger herds had a higher biosecurity when compared to smaller farms (p < 0.01), with no significant associations between AMU and the biosecurity scores. Conclusions Overall, this study evidences that the production system and, to a lesser extent, the biosecurity measures, contribute to the AMR development in commensal E. coli and Enterococcus spp., with antimicrobial usage as the main differential factor, and demonstrates the potential value of these bacteria as bioindicators on pig farms in AMR surveillance programs.
    • Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) prevalence in humans in close contact with animals and measures to reduce on-farm colonisation

      Crespo-Piazuelo, Daniel; Lawlor, Peadar G.; Irish Health Research Board; JPIAMR-2017–1-A (Biomed Central, 2021-08-06)
      Since the 1940s, Staphylococcus aureus has adapted to the use of different antimicrobials to treat infections. Although S. aureus can act as a commensal bacterium, some strains are facultative pathogens and acquiring them can be fatal. In particular, treating infections caused by S. aureus with acquired antimicrobial resistance is problematic, as their treatment is more difficult. Some of these S. aureus variants are methicillin-resistant S. aureus (MRSA) with prevalence across the globe in health-care facilities, community settings and on livestock farms. Apart from humans, MRSA can colonise other animal species, and because of this, resistance to new antimicrobials can appear and jump between species. Livestock and companion animals are particularly important in this regard considering the relatively high usage of antimicrobials in these species. There is a risk to humans who come into direct contact with animals acquiring MRSA but there is also the risk of animals acquiring MRSA from colonised humans. In this review, we summarise studies conducted worldwide to characterise the prevalence of MRSA in veterinarians, farmers and other personnel who come into close contact with animals. Finally, alternative treatment, preventive measures and on-farm strategies to reduce MRSA introduction to a farm and carriage within a herd are discussed.
    • Adding value to food chain information: using data on pig welfare and antimicrobial use on-farm to predict meat inspection outcomes

      Pessoa, Joana; McAloon, Conor; Rodrigues da Costa, Maria; García Manzanilla, Edgar; Norton, Tomas; Boyle, Laura; Teagasc Walsh Scholarship Programme; Meat Industry Ireland (Biomed Central, 2021-10-14)
      Background Using Food Chain Information data to objectively identify high-risk animals entering abattoirs can represent an important step forward towards improving on-farm animal welfare. We aimed to develop and evaluate the performance of classification models, using Gradient Boosting Machine algorithms that utilise accurate longitudinal on-farm data on pig health and welfare to predict condemnations, pluck lesions and low cold carcass weight at slaughter. Results The accuracy of the models was assessed using the area under the receiver operating characteristics (ROC) curve (AUC). The AUC for the prediction models for pneumonia, dorsocaudal pleurisy, cranial pleurisy, pericarditis, partial and total condemnations, and low cold carcass weight varied from 0.54 for pneumonia and 0.67 for low cold carcass weight. For dorsocaudal pleurisy, ear lesions assessed on pigs aged 12 weeks and antimicrobial treatments (AMT) were the most important prediction variables. Similarly, the most important variable for the prediction of cranial pleurisy was the number of AMT. In the case of pericarditis, ear lesions assessed both at week 12 and 14 were the most important variables and accounted for 33% of the Bernoulli loss reduction. For predicting partial and total condemnations, the presence of hernias on week 18 and lameness on week 12 accounted for 27% and 14% of the Bernoulli loss reduction, respectively. Finally, AMT (37%) and ear lesions assessed on week 12 (15%) were the most important variables for predicting pigs with low cold carcass weight. Conclusions The findings from our study show that on farm assessments of animal-based welfare outcomes and information on antimicrobial treatments have a modest predictive power in relation to the different meat inspection outcomes assessed. New research following the same group of pigs longitudinally from a larger number of farms supplying different slaughterhouses is required to confirm that on farm assessments can add value to Food Chain Information reports.
    • Genome-wide association analyses of carcass traits using copy number variants and raw intensity values of single nucleotide polymorphisms in cattle

      Rafter, Pierce; Gormley, Isobel C.; Purfield, Deirdre; Parnell, Andrew C.; Naderi, Saeid; Berry, Donagh P.; Science Foundation Ireland; 14/IA/2576 (Biomed Central, 2021-10-23)
      Background The carcass value of cattle is a function of carcass weight and quality. Given the economic importance of carcass merit to producers, it is routinely included in beef breeding objectives. A detailed understanding of the genetic variants that contribute to carcass merit is useful to maximize the efficiency of breeding for improved carcass merit. The objectives of the present study were two-fold: firstly, to perform genome-wide association analyses of carcass weight, carcass conformation, and carcass fat using copy number variant (CNV) data in a population of 923 Holstein-Friesian, 945 Charolais, and 974 Limousin bulls; and secondly to perform separate association analyses of carcass traits on the same population of cattle using the Log R ratio (LRR) values of 712,555 single nucleotide polymorphisms (SNPs). The LRR value of a SNP is a measure of the signal intensity of the SNP generated during the genotyping process. Results A total of 13,969, 3,954, and 2,805 detected CNVs were tested for association with the three carcass traits for the Holstein-Friesian, Charolais, and Limousin, respectively. The copy number of 16 CNVs and the LRR of 34 SNPs were associated with at least one of the three carcass traits in at least one of the three cattle breeds. With the exception of three SNPs, none of the quantitative trait loci detected in the CNV association analyses or the SNP LRR association analyses were also detected using traditional association analyses based on SNP allele counts. Many of the CNVs and SNPs associated with the carcass traits were located near genes related to the structure and function of the spliceosome and the ribosome; in particular, U6 which encodes a spliceosomal subunit and 5S rRNA which encodes a ribosomal subunit. Conclusions The present study demonstrates that CNV data and SNP LRR data can be used to detect genomic regions associated with carcass traits in cattle providing information on quantitative trait loci over and above those detected using just SNP allele counts, as is the approach typically employed in genome-wide association analyses.
    • Associations between animal and herd management factors, serological response to three respiratory pathogens and pluck lesions in finisher pigs on a farrow-to-finish farm

      Fitzgerald, Rose M; O’Shea, Helen; Manzanilla, Edgar G; Moriarty, John; McGlynn, Hugh; Calderón Díaz, Julia A; Department of Agriculture, Food and the Marine; 14/S/832 (Biomed Central, 2020-12-08)
      Background Serological screening is a common method to monitor antibody response to pathogen exposure, but results could vary due to several factors. This study aimed to quantify animal and management related factors associated with variation in antibody levels in finisher pigs at slaughter, in an Irish farrow-to-finish farm endemically infected with Actinobacillus pleuropneumonia (App), Mycoplasma hyopneumoniae (Mhyo) and swine influenza virus (SIV). A second objective was to estimate differences in antibody levels in pigs presenting pluck lesions. This was an observational study whereby pigs were managed as per routine farm practice. Data on sow parity, number of born alive (NBA) pigs per litter, cross-fostering status, birth and weaning body weight were recorded from 1016 pigs born from one farrowing batch. At slaughter, blood samples were collected for serological analysis and pigs were inspected for presence of enzootic pneumonia (EP)-like lesions, pleurisy, pericarditis and heart condemnations. Pigs were retrospectively classified into three production flows, depending on time spent in each production stage: flow 1 (F1; pigs followed the normal production flow); flow 2 (F2; pigs which were delayed by 1 week from advancing forward); and flow 3 (F3; pigs delayed by > 1 week from advancing forward). A nested case-control design was applied by matching pigs from each flow by sow parity, birth weight and NBA. Results Pigs born from primiparous sows had higher antibody levels for App than those born to parity ≥5 sows (P < 0.05) and there was no association between any of the pathogens investigated and other early life indicators (P > 0.05). Pigs in F1 had lower antibody levels for App but higher antibody levels for SIV than F2 and F3 pigs (P < 0.05). There was no association between pluck lesions and respiratory pathogens (P > 0.05), except for increased antibody levels for Mhyo when EP-like lesions were present (P = 0.006). Conclusion Results indicate that offspring from primiparous sows develop higher antibody levels for App IV toxin when exposed to this disease and that enforcement of a strict all-in/all-out production system would reduce on-farm disease circulation. A high percentage of pigs were affected with EP-like lesions which were associated with higher antibody levels for Mhyo.
    • Genetic control of temperament traits across species: association of autism spectrum disorder risk genes with cattle temperament

      Costilla, Roy; Kemper, Kathryn E; Byrne, Enda M; Porto-Neto, Laercio R; Carvalheiro, Roberto; Purfield, Deirdre C; Doyle, Jennifer L; Berry, Donagh P; Moore, Stephen S; Wray, Naomi R; et al. (Biomed Central, 2020-08-26)
      Background Temperament traits are of high importance across species. In humans, temperament or personality traits correlate with psychological traits and psychiatric disorders. In cattle, they impact animal welfare, product quality and human safety, and are therefore of direct commercial importance. We hypothesized that genetic factors that contribute to variation in temperament among individuals within a species will be shared between humans and cattle. Using imputed whole-genome sequence data from 9223 beef cattle from three cohorts, a series of genome-wide association studies was undertaken on cattle flight time, a temperament phenotype measured as the time taken for an animal to cover a short-fixed distance after release from an enclosure. We also investigated the association of cattle temperament with polymorphisms in bovine orthologs of risk genes for neuroticism, schizophrenia, autism spectrum disorders (ASD), and developmental delay disorders in humans. Results Variants with the strongest associations were located in the bovine orthologous region that is involved in several behavioural and cognitive disorders in humans. These variants were also partially validated in independent cattle cohorts. Genes in these regions (BARHL2, NDN, SNRPN, MAGEL2, ABCA12, KIFAP3, TOPAZ1, FZD3, UBE3A, and GABRA5) were enriched for the GO term neuron migration and were differentially expressed in brain and pituitary tissues in humans. Moreover, variants within 100 kb of ASD susceptibility genes were associated with cattle temperament and explained 6.5% of the total additive genetic variance in the largest cattle cohort. The ASD genes with the most significant associations were GABRB3 and CUL3. Using the same 100 kb window, a weak association was found with polymorphisms in schizophrenia risk genes and no association with polymorphisms in neuroticism and developmental delay disorders risk genes. Conclusions Our analysis showed that genes identified in a meta-analysis of cattle temperament contribute to neuron development functions and are differentially expressed in human brain tissues. Furthermore, some ASD susceptibility genes are associated with cattle temperament. These findings provide evidence that genetic control of temperament might be shared between humans and cattle and highlight the potential for future analyses to leverage results between species.
    • Managing the Calf at Calving Time

      Mee, John F (American Association of Bovine Practitioners, 2008)
      Perinatal mortality rates are increasing internationally, particularly in Holstein-Friesian primiparae. The prevalence of perinatal mortality in US dairy herds is currently 8%. This article outlines our current knowledge of bovine perinatal pathophysiology and presents practical guidelines on management of the calf at calving time. Biophysical profiling of the newborn calf, without sophisticated equipment, is the first step in diagnosing at-risk perinates. Resuscitative techniques adaptable for both the producer and the veterinarian are detailed. In addition, management of prolonged recumbence, hypothermia, failure to suck, umbilical antisepsis and calf movement after calving are discussed. Knowledge gaps constraining future progress towards better newborn calf management are highlighted. Finally, current topics in perinatal mortality are presented.
    • Scenarios to limit environmental nitrogen losses from dairy expansion

      Hoekstra, N.J.; Schulte, R.P.O.; Forrestal, P.J.; Hennessy, Deirdre; Krol, Dominika; Lanigan, Gary J.; Müller, C.; Shalloo, Laurence; Wall, David P.; Richards, Karl G.; et al. (Elsevier, 2020-03-10)
      Increased global demand for dairy produce and the abolition of EU milk quotas have resulted in expansion in dairy production across Europe and particularly in Ireland. Simultaneously, there is increasing pressure to reduce the impact of nitrogen (N) losses to air and groundwater on the environment. In order to develop grassland management strategies for grazing systems that meet environmental targets and are economically sustainable, it is imperative that individual mitigation measures for N efficiency are assessed at farm system level. To this end, we developed an excel-based N flow model simulating an Irish grass-based dairy farm, to evaluate the effect of farm management on N efficiency, N losses, production and economic performance. The model was applied to assess the effect of different strategies to achieve the increased production goals on N utilization, N loss pathways and economic performance at farm level. The three strategies investigated included increased milk production through increased grass production, through increased concentrate feeding and by applying a high profit grass-based system. Additionally, three mitigation measures; low ammonia emission slurry application, the use of urease and nitrification inhibitors and the combination of both were applied to the three strategies. Absolute N emissions were higher for all intensification scenarios (up to 124 kg N ha−1) compared to the baseline (80 kg N ha−1) due to increased animal numbers and higher feed and/or fertiliser inputs. However, some intensification strategies showed the potential to reduce the emissions per ton milk produced for some of the N-loss pathways. The model showed that the assessed mitigation measures can play an important role in ameliorating the increased emissions associated with intensification, but may not be adequate to entirely offset absolute increases. Further improvements in farm N use efficiency and alternatives to mineral fertilisers will be required to decouple production from reactive N emissions.
    • Short communication: Effect of feeding pooled and nonpooled high-quality colostrum on passive transfer of immunity, morbidity, and mortality in dairy calves

      King, Ailbhe; Chigerwe, Munashe; Barry, John; Murphy, John P.; Rayburn, Maire C.; Kennedy, Emer; University of California Davis (American Dairy Science Association, 2020-02)
      Pooling colostrum is commonly practiced on Irish dairy farms. Pooling can result in dilution when colostrums with high and low IgG concentrations are mixed, thereby predisposing calves to failure of passive immunity. The objectives of this study were to compare IgG concentrations in colostrum from individual cows with colostrum pooled from several cows, and assess serum IgG concentrations, morbidity, and mortality among calves fed colostrum from their own dam, from a different cow, or pooled from several cows. We hypothesized that pooling colostrum reduces IgG concentration due to dilution compared with colostrum from individual cows, and that calves fed pooled colostrum achieve lower serum IgG concentrations than calves fed colostrum from individual cows. Calves were randomly assigned to 1 of 3 groups: (1) fed colostrum from their own dam (n = 20); (2) fed colostrum from a different dam (n = 20); or (3) fed pooled colostrum (n = 18). A sample of colostrum fed to each calf was collected. Serum samples were collected from calves at birth (0 h) and at 24 h after colostrum feeding. Colostrum and serum IgG concentrations were measured by radial immunodiffusion. Calves were weighed at birth and at weaning, and the health status of each calf was assessed twice daily. Health assessment was based on general demeanor, rectal temperature, fecal consistency, respiratory rate, and the presence of cough, nasal, or ocular discharge. Colostrum and serum IgG concentrations, and weaning weights were compared using ANOVA. Associations between group and morbidity or mortality rates were compared using χ2 or Fisher’s exact tests. Median and 95% confidence intervals (95% CI) of IgG concentrations of colostrum were 99.4 (81.8–111.5), 95.2 (84.1–107.2), and 100.7 (90.5–104.4) g/L for own dam, different dam, and pooled groups, respectively. We did not find any differences in colostrum IgG concentrations among the colostrum sources. Median (95% CI) serum IgG concentrations at 24 h were 52.0 (45.6–65.9), 55.7 (51.2–65.9), and 53.1 (46.2–63.7) g/L for calves that received colostrum from own dam, different dam, and pooled, respectively. All calves achieved adequate passive immunity. Serum IgG concentrations at 24 h, weaning weights, and proportions of morbidity and mortality were not different among the 3 groups. Our results suggest that on dairy farms where median colostrum IgG concentrations are high and colostrum management is optimal, pooling has a minimal effect on passive immunity and subsequent calf health.
    • Sward type alters the relative abundance of members of the rumen microbial ecosystem in dairy cows

      Smith, Paul E.; Enriquez-Hidalgo, Daniel; Hennessy, Deirdre; McCabe, Matthew S.; Kenny, David A.; Kelly, Alan K.; Waters, Sinéad M.; FACCE ERA GAS; Irish Dairy Levy Trust; European Union; et al. (Springer Science and Business Media LLC, 2020-06-09)
      The performance of ruminant livestock has been shown to beneft from the enhanced nutritive value and herbage yield associated with clover incorporation in the grazing sward. However, little research to date has been conducted investigating the efects of mixed swards containing white clover on the composition of the rumen microbiome. In this study, the rumen microbial composition of late lactation dairy cows grazing perennial ryegrass only (PRG; n=20) or perennial ryegrass and white clover (WCPRG; n=19) swards, was characterised using 16S rRNA amplicon sequencing. PERMANOVA analysis indicated diet signifcantly altered the composition of the rumen microbiome (P=0.024). Subtle shifts in the relative abundance of 14 bacterial genera were apparent between diets, including an increased relative abundance of Lachnospira (0.04 vs. 0.23%) and Pseudobutyrivibrio (1.38 vs. 0.81%) in the WCPRG and PRG groups, respectively. The composition of the archaeal community was altered between dietary groups, with a minor increase in the relative abundance of Methanosphaera in the WCPRG observed. Results from this study highlight the potential for sward type to infuence the composition of the rumen microbial community.
    • Experimental challenge with bovine respiratory syncytial virus in dairy calves: bronchial lymph node transcriptome response

      Johnston, Dayle; Earley, Bernadette; McCabe, Matthew S.; Lemon, Ken; Duffy, Catherine; McMenamy, Michael; Cosby, S. Louise; Kim, JaeWoo; Blackshields, Gordon; Taylor, Jeremy F.; et al. (Springer Science and Business Media LLC, 2019-10-14)
      Bovine Respiratory Disease (BRD) is the leading cause of mortality in calves. The objective of this study was to examine the response of the host’s bronchial lymph node transcriptome to Bovine Respiratory Syncytial Virus (BRSV) in a controlled viral challenge. Holstein-Friesian calves were either inoculated with virus (103.5TCID50/ml×15ml) (n=12) or mock challenged with phosphate bufered saline (n=6). Clinical signs were scored daily and blood was collected for haematology counts, until euthanasia at day 7 post-challenge. RNA was extracted and sequenced (75bp paired-end) from bronchial lymph nodes. Sequence reads were aligned to the UMD3.1 bovine reference genome and diferential gene expression analysis was performed using EdgeR. There was a clear separation between BRSV challenged and control calves based on gene expression changes, despite an observed mild clinical manifestation of the disease. Therefore, measuring host gene expression levels may be benefcial for the diagnosis of subclinical BRD. There were 934 diferentially expressed genes (DEG) (p<0.05, FDR <0.1, fold change >2) between the BRSV challenged and control calves. Over-represented gene ontology terms, pathways and molecular functions, among the DEG, were associated with immune responses. The top enriched pathways included interferon signaling, granzyme B signaling and pathogen pattern recognition receptors, which are responsible for the cytotoxic responses necessary to eliminate the virus.
    • Effect of Early Calf-Hood Nutrition on the Transcriptional Regulation of the Hypothalamic-Pituitary-Testicular axis in Holstein-Friesian Bull Calves

      English, A. M.; Byrne, C. J.; Cormican, P; Waters, S. M.; Fair, S.; Kenny, D. A.; Department of Agriculture, Food and the Marine; Irish Research Council; 11/S/116; GOIPG/2013/1391 (Springer Science and Business Media LLC, 2018-11-08)
      The aim of this study was to investigate the effect of early calf-hood nutrition on the transcriptomic profile of the arcuate nucleus of the hypothalamus, anterior pituitary and testes in Holstein-Friesian bulls. Holstein-Friesian bull calves with a mean (±S.D.) age and bodyweight of 19 (±8.2) days and 47.5 (±5.3) kg, respectively, were offered a high (n = 10) or low (n = 10) plane of nutrition in order to achieve an overall growth rate of 1.2 and 0.5 kg/day. At 126 (±3) days of age, calves were euthanized, hypothalamus (arcuate region), anterior pituitary and testicular parenchyma samples were harvested and RNAseq analysis was performed. There were 0, 49 and 1,346 genes differentially expressed in the arcuate nucleus, anterior pituitary and testicular tissue of bull calves on the low relative to the high plane of nutrition, respectively (P < 0.05; False Discovery Rate <0.05). Cell cycle processes in the anterior pituitary were down regulated in the low relative to the high plane of nutrition; there was no differential expression of genes related to reproductive processes. Gene expression involved in cholesterol and androgen biosynthesis in the testes were down regulated in animals on the low plane of nutrition. This study provides insight into the effect of early life plane of nutrition on the regulation of the HPT axis.
    • Irish pig farmer’s perceptions and experiences of tail and ear biting

      Haigh, Amy; O'Driscoll, Keelin; Department of Agriculture, Food and the Marine (Springer Science and Business Media LLC, 2019-12-17)
      Abnormal behaviours such as ear and tail biting of pigs is of significant welfare and economic concern. Currently, pig welfare legislation is under renewed focus by the EU commission and is likely to be enforced more thoroughly. The legislation prohibits routine tail docking and requires adequate enrichment to be provided. In Ireland, taildocking is still the most utilised control mechanism to combat tail biting, but biting is still widespread even in taildocked pigs. In addition, as pig farms are almost all fully slatted, bedding type material cannot be provided. Thus, the opinions, and practices of farmers in countries like Ireland, which may need to make significant adaptations to typical pig management systems soon, need to be considered and addressed. We carried out a survey of pig farmers during 2015 in order to gain a greater understanding of the extent of biting on Irish farms, perception on the most important preventive measures, current enrichment use and actions following outbreaks. Fifty-eight farmers from 21 Counties responded with an average herd size of 710 ± 597 sows (range 90–3000 sows). Only two farms had experienced no biting in the last year. Of the farms that had experienced tail biting (88%), 86% had also experienced ear biting. The most common concerns relating to biting were condemnation and reduced productivity of bitten pigs with both receiving an average score of 4 (most serious). Ear biting occurred most commonly in the 2nd stage (approximately 47–81 days from weaning) weaner and tail biting in the finishing stage. The most important preventive measures were felt to be taking care of animal health, restricting density, maintaining an even quality of feed/ content and maintaining good air movement. Sixty-five percent of respondents added additional enrichment following an outbreak. Chains were the most common form of enrichment currently used (83%). Those not using chains favoured wood, toys and rope (17%). Identification of the most effective and accessible control and prevention measures both for the animals and for the farming community is thus essential. Improved understanding of the concerns and practices of producers, which this survey contributes to, is a first step towards this aim.
    • Current antimicrobial use in farm animals in the Republic of Ireland

      Martin, Hannah; Manzanilla, Edgar Garcia; More, Simon J.; O’Neill, Lorcan; Bradford, Lisa; Carty, Catherine I.; Collins, Áine B.; McAloon, Conor G.; Food Safety Promotion Board; Fund No. 04– 2018 (Springer Science and Business Media LLC, 2020-06-26)
      Abstract Antimicrobial resistance has been recognised as one of the most difficult challenges facing human and animal health in recent decades. The surveillance of antimicrobial use in animal health plays a major role in dealing with the growing issue of resistance. This paper reviews current data available on antimicrobial use in farmed animals in the Republic of Ireland, including each of the major livestock production sectors; pigs, poultry, dairy, beef and sheep. A systematic literature search was conducted to identify relevant published literature, and ongoing research was identified through the network of authors and searches of each of the research databases of the main agriculture funding bodies in Ireland. The varying quantities and quality of data available across each livestock sector underlines the need for harmonisation of data collection methods. This review highlights the progress that has been made regarding data collection in the intensive production sectors such as pigs and poultry, however, it is clear there are significant knowledge gaps in less intensive industries such as dairy, beef and sheep. To comply with European regulations an antimicrobial data collection system is due to be developed for all food-producing animals in the future, however in the short-term surveillance studies have allowed us to build a picture of current use within the Republic of Ireland. Further studies will allow us to fill current knowledge gaps and build a more comprehensive overview of antimicrobial use in farm animals in Ireland.
    • Heart to spine measurements to detect left atrial enlargement in dogs with mitral insufficiency

      Sánchez Salguero, Xavier; Prandi, David; Llabrés-Díaz, Francisco; Manzanilla, Edgar G.; Badiella, Llorenç; Bussadori, Claudio (Springer Science and Business Media LLC, 2019-11-20)
      Background: Radiography is useful to determine left atrial (LA) size when echocardiography is not available. Recently, the authors have described Radiographic Left Atrial Dimension (RLAD) as a new radiographic measurement to assess LA size. The objective of this study was to assess the clinical usefulness of 2 new radiographic measurements to detect and quantify left atrial enlargement (LAE) compared to RLAD and using left atrium to aortic root (LA/Ao) ratio as gold standard. These new measurements, bronchus-to-spine (Br-Spine) and RLAD-to-spine (RLAD-Spine) may be more precise in cases were LA boundaries are not well defined. Fifty dogs, 25 with and 25 without LAE were recruited. Reference LA/Ao ratio was assessed by 2D echocardiography and LAE was considered if LA/Ao > 1.6. Br-spine was measured as a straight vertical line from the main stem bronchus to the ventral border of the vertebra situated immediately dorsal to the heart base. RLAD-Spine was measured from RLAD endpoint perpendicularly to spine. The correlation of RLAD, Br-Spine and RLAD-Spine methods with LA/Ao and their sensitivity and specificity for detecting LAE were calculated. Receiver Operating Characteristic (ROC) curves were used to estimate the optimal cut-off for each method. Results: Correlations between Br-Spine, RLAD-Spine, RLAD and LA/Ao ratio were − 0.66, − 0.76 and 0.89 respectively (P < 0.001). Sensitivity at the optimal cut-off values for detecting LAE were 32.0, 64.0 and 96.0%, respectively. Specificity was 96.0% in all cases. Conclusion: Br-Spine and RLAD-Spine were less sensitive radiographic measurements than RLAD in detecting LAE in dogs. Both Br-Spine and RLAD-Spine may not be good alternatives to RLAD.