Now showing items 1-20 of 742

    • Growth performance and hematological changes of weaned beef calves diagnosed with respiratory disease using respiratory scoring and thoracic ultrasonography

      Cuevas-Gómez, Inmaculada; McGee, Mark; McCabe, Matthew; Cormican, Paul; O’Riordan, Edward; McDaneld, Tara; Earley, Bernadette; US-Ireland Tripartite Grant; 2018US-IRL200 (Oxford University Press (OUP), 2020-10-23)
      This study investigated (i) the effect of clinical bovine respiratory disease (BRD) and associated lung consolidations on growth performance and hematological profiles of recently weaned beef calves and (ii) the relationship between clinical respiratory signs and lung consolidation detected by thoracic ultrasonography (TUS). One hundred and fifty-three weaned beef calves (209 (SD; 35.8) days old and 306 (SD; 26.3) kg, at arrival) purchased and transported from auction markets were accommodated indoors in concrete slatted floor pens. Calves were weighed weekly from arrival until d 28 and on d 65 post-arrival. Assessment of BRD and blood sample collection for hematological profiles were performed on scheduled days (at arrival, on d 7, 14 and 28) and on other days upon BRD diagnosis. Animals were assessed for BRD using a total clinical respiratory score (CRS) of five clinical signs (rectal temperature, ear position, cough, nasal secretion and eye secretion with each ranging from normal (0) to abnormal (3)), and TUS scores (normal (0) to lung consolidation ≥ 1 cm2 (2)). Based on CRS, 35% of calves were CRS+ (CRS ≥5) and 65% were CRS- (CRS <5). Although no lung consolidations (TUS-) were detected at arrival, 34% of calves developed lung consolidation (≥ 1 cm2 ) (TUS+) during the first 28 d post-arrival. Only fever (>39.6o C) and nasal discharge were weakly associated (r 0.19, P <0.05) with lung consolidation. On the day of BRD detection, neutrophil number and neutrophil:lymphocyte ratio was 58% and 73% greater, respectively, in BRD calves with lung consolidation compared to healthy calves. From d 0 to 65, calf ADG did not differ (P >0.05) between CRS+ and CRS- calves, but was 0.09 kg/d lower (P <0.05) for TUS+ compared to TUS- calves. Calves classified as BRD (CRS+TUS ≥5) with lung consolidation had lower (P <0.05) ADG from arrival until d 28 than healthy calves and BRD calves without lung consolidation (0.11 ± 0.10 vs. 0.53 ± 0.07 vs. 0.57 ± 0.10 kg/d, respectively); however, no differences in ADG were observed from d 0 to 65. Conventional methods to diagnose BRD failed to detect calves with lung lesions. Thoracic ultrasonography is a useful tool to detect lung lesions and its implementation in combination with CRS should provide a more accurate and early diagnosis of BRD, which is fundamental to successful treatment, animal welfare and growth performance.
    • Strategies to Meet Nutritional Requirements and Reduce Boar Taint in Meat from Entire Male Pigs and Immunocastrates

      Bee, Giuseppe; Quiniou, Nathalie; Maribo, Hanne; Zamaratskaia, Galia; Lawlor, Peadar G. (MDPI AG, 2020-10-23)
      This paper reviews the current knowledge on the nutritional requirements of entire male and immunocastrated pigs to obtain an efficient growth, low boar taint level, and good carcass and meat quality. We present the reasons for offering entire males ad libitum access to the diets in order to optimize their protein deposition potential. Boar taint is one of the major issues in the production of entire males; therefore, the impact of various skatole- and indole-reducing feed ingredients is discussed regarding their efficiency and the possible mechanism affecting skatole and indole production in the hindgut. Entire males have lean carcasses, so their intramuscular fat content can be lower than that of surgical castrates or females and the adipose tissue can be highly unsaturated. The possible nutritional strategies to counteract these effects are summarized. We conclude that immunocastrates can be fed similarly to entire males until the second vaccination. However, due to the metabolic changes occurring shortly after the second vaccination, the requirements for essential amino acids are markedly lower in immunocastrates than in entire males.
    • Early immune suppression leads to uncontrolled mite proliferation and potent host inflammatory responses in a porcine model of crusted versus ordinary scabies

      Bhat, Sajad A.; Walton, Shelley F.; Ventura, Tomer; Liu, Xiaosong; McCarthy, James S.; Burgess, Stewart T. G.; Mounsey, Kate E.; Australian Research Council; Australian National Health and Medical Research Council; DE120101701; et al. (Public Library of Science (PLoS), 2020-09-04)
      Scabies is a neglected tropical disease of global significance. Our understanding of hostparasite interactions has been limited, particularly in crusted scabies (CS), a severe clinical manifestation involving hyper-infestation of Sarcoptes scabiei mites. Susceptibility to CS may be associated with immunosuppressive conditions but CS has also been seen in cases with no identifiable risk factor or immune deficit. Due to ethical and logistical difficulties with undertaking research on clinical patients with CS, we adopted a porcine model which parallels human clinical manifestations. Transcriptomic analysis using microarrays was used to explore scabies pathogenesis, and to identify early events differentiating pigs with ordinary (OS) and crusted scabies. Pigs with OS (n = 4), CS (n = 4) and non-infested controls (n = 4) were compared at pre-infestation, weeks 1, 2, 4 and 8 post-infestation. In CS relative to OS, there were numerous differentially expressed genes including pro-inflammatory cytokines (IL17A, IL8, IL19, IL20 and OSM) and chemokines involved in immune cell activation and recruitment (CCL20, CCL27 and CXCL6). The influence of genes associated with immune regulation (CD274/PD-L1 and IL27), immune signalling (TLR2, TLR8) and antigen presentation (RFX5, HLA-5 and HLA-DOB) were highlighted in the early host response to CS. We observed similarities with gene expression profiles associated with psoriasis and atopic dermatitis and confirmed previous observations of Th2/17 pronounced responses in CS. This is the first comprehensive study describing transcriptional changes associated with the development of CS and significantly, the distinction between OS and CS. This provides a basis for clinical follow-up studies, potentially identifying new control strategies for this severely debilitating disease
    • Mitigation of greenhouse gas emissions from beef cattle production systems

      Samsonstuen, Stine; Åby, Bente A.; Crosson, Paul; Beauchemin, Karen A.; Aass, Laila; Norwegian University of Life Sciences (Informa UK Limited, 2020-08-27)
      The whole-farm model HolosNorBeef was used to estimate the efficiency of GHG emission mitigation strategies in Norwegian beef cattle herds. Various mitigation scenarios, involving female reproductive performance (i.e. calf mortality rate and the number of calves produced per cow per year), production efficiency of young bulls for slaughter (i.e. age at slaughter and carcass weight), and supplementation of an inhibitor currently reported as promising for enteric methane (CH4) inhibition (3-nitrooxypropanol; 3-NOP) was investigated in herds of British and Continental breeds. Reducing calf mortality and increasing the number of produced calves per cow per year both reduced emission intensities by 3% across breeds. Continental breeds showed greater potential of reducing emission intensities due to increased carcass production. Combining mitigation options in a best case scenario reduced the total emissions by 11.7% across breeds. The emission intensities could be further reduced by 8.3% with the use of 3-NOP.
    • Effect of teatcup removal settings on milking efficiency and milk quality in a pasture-based automatic milking system

      Silva Boloña, P.; Reinemann, D.J.; Upton, J.; Teagasc Walsh Fellowship Programme; University of Wisconsin–Madison; Lely (American Dairy Science Association, 2019-09)
      In automatic milking systems (AMS), it is important to maximize the amount of milk harvested per day to increase profitability. One strategy to achieve this goal is to reduce the time it takes to milk each cow. Several studies in conventional milking systems have shown that milking time can be reduced by increasing the milk flow rate at which the teatcup is removed. One study analyzed the effect of increasing the milk flow switch point on milking time in a confinement AMS. No research has been conducted on teatcup removal settings in pasture-based automatic milking systems. Furthermore, not all AMS remove the teatcups based on absolute milk flow rate (kg/min); hence, it is important to study alternative strategies. The aim of this experiment was to measure the effect of 3 novel teatcup removal strategies on box time (time in the AMS), milking time, somatic cell count (SCC), and milk production rate of cows milked in a pasture-based automatic milking system. Each teatcup removal strategy in this study was applied for a period of 1 wk to 1 of 3 groups of cows and then switched to the following group until cows had transitioned through all treatments. The teatcup removal strategies consisted of removing the teatcup when the quarter flow rate fell below 20% of the quarter rolling average milk flow rate (TRS20), when quarter milk flow rate was below 30% of the rolling average milk flow rate (TRS30), and when quarter milk flow rate dropped below 50% of the rolling average milk flow rate (TRS50). A limit prevented teatcup removal if the calculated milk flow rate for teatcup removal was above 0.5 kg/min. This limit was in place for all treatments; however, it only affected the TRS50 treatment. The TRS30 strategy had 9-s shorter milking time and 11-s shorter box time than the TRS20 removal strategy. The TRS50 strategy had 8-s shorter milking time and 9-s shorter box time than the TRS20 teatcup removal strategy. There was no significant difference in milking time or box time between the TRS30 and TRS50 teatcup removal strategies, probably due to the large variability in milk flow rate at teatcup removal. The TRS20 and TRS30 strategies did not differ in SCC or milk production rate. The 0.5 kg/min limit, which affected roughly 25% of milkings in the TRS50 treatment, may have distorted the effect that this setting had on milk time, box time, milk production rate, or SCC. The difference in box time for the TRS30 and TRS50 strategies could allow for more than 3 extra milkings per day
    • Fertility of frozen sex-sorted sperm at 4 × 106 sperm per dose in lactating dairy cows in seasonal-calving pasture-based herds

      Maicas, C.; Holden, S.A.; Drake, E.; Cromie, A.R.; Lonergan, P.; Butler, S.T.; Irish Dairy Levy Trust; Munster Bovine; Meat Industry Ireland; Glanbia; et al. (American Dairy Science Association, 2020-01)
      The objective was to evaluate the reproductive performance of frozen sex-sorted sperm at 4 × 106 sperm per dose (SexedULTRA 4M, Sexing Technologies, Navasota, TX) relative to frozen conventional sperm in seasonal-calving pasture-based dairy cows. Semen from Holstein-Friesian (n = 8) and Jersey (n = 2) bulls was used. Four of the Holstein bulls used were resident at or near a sex-sorting laboratory (Cogent, UK, or ST Benelux, the Netherlands). The remaining 6 bulls were located at studs in Ireland. For these 6 bulls, ejaculates were collected, diluted with transport medium, and couriered to Cogent in parcel shippers. Transit time from ejaculation to arrival at the sorting laboratory was 6 to 7 h. For all bulls, ejaculates were split and processed to provide frozen conventional sperm (CONV) at 15 × 106 sperm per straw and frozen sex-sorted (SS) sperm at 4 × 106 sperm per straw and used to inseminate lactating dairy cows after spontaneous estrus. Pregnancy diagnosis was performed by ultrasound scanning (n = 7,246 records available for analysis). Generalized linear mixed models were used to examine effects on pregnancy per AI (P/AI) at first artificial insemination, with sperm treatment (CONV vs. SS), bull (n = 10), and treatment × bull interaction as the fixed effects, and herd (n = 142) as a random effect. Overall, P/AI was greater for cows inseminated with CONV than for those inseminated with SS (59.9% vs. 45.5%; 76.0% relative to CONV). This study was not designed to compare resident bulls vs. shipped ejaculates, but the magnitude of the difference between P/AI achieved by CONV and SS was apparently less for resident bulls (60.3% vs. 50.2%) than for shipped ejaculates (58.6% vs. 40.7%). We discovered a treatment × bull interaction for shipped ejaculates (P/AI ranged from 45 to 86% relative to CONV) but not for the resident bulls (P/AI ranged from 81 to 87% relative to CONV). Relative P/AI of SS compared with CONV was greater in cows with high or average fertility potential (76.1% and 78.3%, respectively) than in cows with low fertility potential (58.1%). In 33.1% of the enrolled herds, the P/AI achieved with SS was 90% or more of the P/AI achieved with CONV; this was mainly explained by herds in which SS performed exceptionally well but CONV performed poorly. In conclusion, SS had lower overall P/AI compared with CONV; however, P/AI achieved with SS was dependent on the bull, fertility potential of the cow, and herd. Strategies to improve the P/AI with SS in seasonal-calving pasture-based lactating dairy cows require further research.
    • Validation of an ear tag–based accelerometer system for detecting grazing behavior of dairy cows

      Pereira, G.M.; Heins, B.J.; O'Brien, Bernadette; McDonagh, A.; Lidauer, L.; Kickinger, F.; USDA National Institute of Food and Agriculture; Science Foundation Ireland; 2012-51300-20015 (Elsevier, 2020-02-20)
      The objective of the study was to develop a grazing algorithm for an ear tag–based accelerometer system (Smartbow GmbH, Weibern, Austria) and to validate the grazing algorithm with data from a noseband sensor. The ear tag has an acceleration sensor, a radio chip, and temperature sensor for calibration and it can monitor rumination and detect estrus and localization. To validate the ear tag, a noseband sensor (RumiWatch, Itin and Hoch GmbH, Liestal, Switzerland) was used. The noseband sensor detects pressure and acceleration patterns, and, with a software program specific to the noseband, pressure and acceleration patterns are used to classify data into eating, ruminating, drinking, and other activities. The study was conducted at the University of Minnesota West Central Research and Outreach Center (Morris, MN) and at Teagasc Animal and Grassland Research and Innovation Centre (Moorepark, Fermoy, Co. Cork, Ireland). During May and June 2017, observational data from Minnesota and Ireland were used to develop the grazing algorithm. During September 2018, data were collected by the ear tag and noseband sensor from 12 crossbred cows in Minnesota for a total of 248 h and from 9 Holstein-Friesian cows in Ireland for a total of 248 h. A 2-sided t-test was used to compare the percentage of grazing and nongrazing time recorded by the ear tag and the noseband sensor. Pearson correlations and concordance correlation coefficients (CCC) were used to evaluate associations between the ear tag and noseband sensor. The percentage of total grazing time recorded by the ear tag and by the noseband sensor was 37.0% [95% confidence interval (CI): 32.1 to 42.0] and 40.5% (95% CI: 35.5 to 45.6), respectively, in Minnesota, and 35.4% (95% CI: 30.6 to 40.2) and 36.9% (95% CI: 32.1 to 41.8), respectively, in Ireland. The ear tag and noseband sensor agreed strongly for monitoring grazing in Minnesota (r = 0.96; 95% CI: 0.94 to 0.97, CCC = 0.95) and in Ireland (r = 0.92; 95% CI: 0.90 to 0.94, CCC = 0.92). The results suggest that there is potential for the ear tag to be used on pasture-based dairy farms to support management decision-making.
    • An assessment of the production, reproduction, and functional traits of Holstein-Friesian, Jersey × Holstein-Friesian, and Norwegian Red × (Jersey × Holstein-Friesian) cows in pasture-based systems

      McClearn, B.; Delaby, L.; Gilliland, T.J.; Guy, C.; Dineen, M.; Coughlan, F.; Buckley, Frank; McCarthy, B.; Dairy Research Ireland; Teagasc Walsh Scholarship Programme (Elsevier, 2020-04-03)
      Pasture-based production systems typically require highly fertile, healthy, and robust genetics, with greater emphasis on milk solids (MSo; kg of fat + protein) production as opposed to milk yield. This study assessed milk production, production efficiency, reproductive performance, body weight (BW), body condition score, and functional traits in 3 different dairy cow genotypes: Holstein-Friesian (HF), Jersey × Holstein-Friesian (JEX), and Norwegian Red × (Jersey × Holstein- Friesian) (3-way). The 3 genotypes were rotationally grazed on 4 different grazing treatments after calving in spring and were stocked at a rate of 2.75 cows/ha. Holstein-Friesian cows produced higher daily and total milk yields compared with JEX and 3-way cows (5,718 vs. 5,476 and 5,365 kg/cow, respectively). However, JEX and 3-way cows had higher milk fat and protein contents (4.86 and 4.75%, respectively, for JEX and 3.87 and 3.88%, respectively, for 3-way) compared with HF (4.52 and 3.72%), resulting in similar MSo yield for JEX and HF (469 and 460 kg/cow) and slightly lower MSo yield for 3-way (453 kg/cow) compared with JEX. As parity increased, milk and MSo yield per cow increased. Reproductive performance was not significantly different between the 3 genotypes, which had similar 24-d submission rates, 6-wk pregnancy rates, and overall pregnancy rates over the 4-yr period. No difference in calving difficulty, incidence of mastitis, or incidence of lameness was observed among the 3 genotypes. Body weight was significantly different among all 3 genotypes, with HF being the heaviest followed by 3-way and JEX (530, 499, and 478 kg, respectively), and 3-way cows had a higher body condition score throughout lactation compared with HF and JEX cows. The differences in BW coupled with similar MSo production resulted in JEX cows having the highest production efficiency (4.58 kg of MSo/kg of metabolic BW), 3-way cows being intermediate (4.30 kg of MSo/kg of metabolic BW), and HF cows having the lowest (4.16 kg of MSo/kg of metabolic BW). In conclusion, HF herds with poor reproductive performance and low milk fat and protein contents are likely to benefit considerably from crossbreeding with Jersey, and all herds are likely to benefit in terms of production efficiency. However, where herd performance, particularly in relation to reproductive performance, is comparable with HF in the current study, crossbreeding with Jersey or Norwegian Red is unlikely to lead to significant improvements in overall herd performance.
    • Evaluation of an investigative model in dairy herds with high calf perinatal mortality rates in Switzerland

      Mock, Thomas; Mee, John F.; Detwiler, Martina; Rodriguez-Campos, Sabrina; Hüsler, Jürg; Michel, Brigitte; Häfliger, Irene M.; Drogemuller, Cord; Bodmer, Michele; Hirsbrunner, Gaby; et al. (Theriogenology, 2020-02-24)
      The objective of this study was to evaluate an investigative model which encompassed the risk factors, incidence, timing and causes of perinatal mortality (PM) (0–48 h) on high risk dairy farms (PM of >5% in the previous year) in Switzerland. This pilot-study was carried out on 47 predominantly Holstein PM calves from 21 dairy farms, between September 2016 and January 2018. Gross pathological examinations of calves and placentae as well as histopathological examinations of internal organs and placental tissue were performed. Further investigations included microbiological examinations: broad-spectrum bacterial and fungal culture, detection of Chlamydia abortus, Coxiella burnetii, pathogenic Leptospira spp. and Neospora caninum by real-time PCR (qPCR) and of bovine viral diarrhoea virus (BVDV) by Ag-ELISA. Maternal blood samples were used for serology of bovine herpesvirus 1 (BHV-1), Brucella abortus, Chlamydia abortus, Coxiella burnetii and nine pathogenic leptospiral serovars and the evaluation of trace element status. A questionnaire was completed with the farmer, which included general farm characteristics and case-related data. Inbreeding coefficients (IC) were calculated for pure-bred matings. At the farm-level, the PM rate was 10.0% (5.3–28.2%) and at the cow-level, 11.5%. These values, from high-risk farms, were approximately five-times higher than the contemporary national bovine PM rate (2.3%) in Switzerland. The risk factors associated with these high PM rates were the self-selection of high risk herds, the high proportion of primiparae in these herds (45%) and the evidence of widespread pathogenic infections on these farms (exposure: 67% of herds, 53% of dams; infection: 57% of herds, 45% of calves). The majority (68.1%) of calves died intrapartum. The most commonly diagnosed initiating/ultimate cause of death (UCOD) was infection (34%) of which Coxiella burnetii was the most frequently detected pathogen, by antigen. The most frequently diagnosed proximate cause of death (PCOD) was asphyxia (44.7%), though multiple PCOD was also common (21.3%). This study was the first detailed investigation of bovine PM in Switzerland. Infectious causes were diagnosed more frequently than expected. While the findings from these high PM Swiss herds may have limited external validity, the investigative model adopted and the detailed research methodologies employed can be replicated and re-evaluated, respectively, in future studies on PM internationally.
    • Prepubertal nutrition alters Leydig cell functional capacity and timing of puberty

      Anand-Ivell, Ravinder; Byrne, Colin J.; Arnecke, Jonas; Fair, Sean; Lonergan, Pat; Kenny, David A.; Ivell, Richard; Department of Agriculture, Food and the Marine; 11/S/116 (Public Library of Science (PLoS), 2019-11-21)
      Leydig cell functional capacity reflects the numbers and differentiation status of the steroidogenic Leydig cells in the testes and becomes more or less fixed in early adulthood with the final establishment of the hypothalamo-pituitary-gonadal (HPG) axis after puberty. Factors influencing Leydig cell functional capacity and its role in puberty are poorly understood. Using a bovine model of dairy bulls fed four different nutritional regimes from 1 month to 12 months, and applying circulating Insulin-like peptide 3 (INSL3) as an accurate biomarker of Leydig cell functional capacity, showed that a high plane of nutrition in the first 6 months of life, but not later, significantly increased INSL3 in young adulthood. Moreover, INSL3 concentration at 4 months indicated a marked differential in early feeding regime and correlated well (negatively) with the timing of puberty, as reflected by the age in days for the first production of an ejaculate with >50 million sperm and >10% forward motility, as well as with testis size at 18 months. Reversing the diet at 6 months was unable to rectify the trend in either parameter, unlike for other parameters such as testosterone, body weight, and scrotal circumference. This study has shown that early prepubertal nutrition is a key factor in the development of Leydig cell functional capacity in early adulthood and appears to be a key driver in the dynamic progression of puberty.
    • Factors affecting ewe longevity on sheep farms in three European countries

      McLaren, A.; McHugh, Noirin; Lambe, N. R.; Pabiou, T.; Wall, E.; Boman, I. A.; Department of Agriculture, Food and the Marine; Research Council of Norway; Norwegian Association of Sheep and Goat Breeders; UK Department for Environment, Food and Rural Affairs; et al. (Elsevier BV, 2020-08)
      The ability to identify ewes that can outperform their contemporaries, in terms of how long they remain productive in the flock, will help towards improving flock efficiency and profitability. The main objectives of this study were to: (1) identify the main reasons for mortality or culling within diverse sheep production systems in Ireland, Norway and UK; (2) investigate the influence of early life factors on ewe longevity within each of these systems; and (3) determine whether common approaches or recommendations could be employed to improve ewe longevity. The main reasons for mortality or culling were, in addition to old age, mastitis (Irish and Norwegian sheep) and tooth loss (UK hill sheep). In each country, there were significant differences in age at last lambing due to the year the ewe was born (but in no consistent pattern), and due to her flock of birth (P < 0.05). From the Norwegian data, there was some indication ewes from younger dams lambed for the last time at a younger age, however, this trend was not seen in the Irish or UK data. Ewes born as singletons, in the Irish data, lambed for the last time at an older age than those that had been born in larger litters, although this was not observed in the other data sets. Age at first lambing and some breed proportions (proportion of Texel and Suffolk particularly) of the animal (both not fitted in the Norwegian or UK analyses) were found to have a highly significant (P < 0.0001) effect on age at last lambing in the Irish analyses. The results suggest that longevity is influenced by a range of different factors and the early life predictors investigated could not be used to provide consistent recommendations across countries, production systems and breeds that would influence ewe longevity. One common definition or solution to select ewes for longer productive life in divergent sheep flocks may not be appropriate.
    • Evaluation of the n-alkane technique for estimating the individual intake of dairy cows consuming diets containing herbage and a partial mixed ration

      Wright, M.M.; Auldist, M.J.; Kennedy, Emer; Dunshea, F.R.; Galvin, N.; Hannah, M.C.; Wales, W.J.; DJPR; Victoria; Dairy Australia (Elsevier BV, 2020-07)
      Estimation of dry matter intake (DMI) using the n-alkane technique was evaluated in lactating dairy cows fed fresh herbage and a partial mixed ration (PMR). Four dietary treatments were investigated in a 2 × 2 factorial experiment using 16 Holstein-Friesian dairy cows. Dietary treatments were combinations of low and high amounts of fresh herbage (8 or 14 kg DM/cow per day) and PMR supplement (6 or 12 kg DM/cow per day). The pre-experimental period was 14 days followed by a 10-day experimental period. Cows were housed in individual metabolism stalls to allow for accurate measurement of DMI and total fecal output. Fecal n-alkane recovery rates were calculated to determine the most accurate corrections for incomplete fecal n-alkane recovery. The n-alkane technique accurately estimated DMI when corrected for incomplete fecal recovery using both published recovery rates and recovery rates calculated in this experiment. The most accurate application of recovery rates was with those calculated for each combination of dietary treatments, compared with using an average recovery rate. This research has important implications for the future use of the n-alkane technique, especially in PMR feeding systems. The discrepancy between estimated (when treatment recovery rates were applied) and measured herbage DMI increased with the amount of herbage offered but was not affected by amount of PMR. It was also found that the recovery rates of all natural n-alkanes increased as the amount of herbage increased. This research demonstrates that the n-alkane technique can be used to accurately estimate individual cow intake when fresh herbage and PMR are offered separately, evidenced by strong Lin’s concordance estimates.
    • Application of next generation sequencing for the elucidation of genes and pathways involved in the host response to bovine respiratory syncytial virus

      Johnston, D; Earley, B; McCabe, M. S.; Blackshields, G.; Lemon, K.; Duffy, C.; McMenamy, M.; Cosby, S. L.; Kim, J.; Taylor, J. F.; et al. (2021-06-16)
      Objective: To identify genes and pathways involved in the host response to bovine respiratory syncytial virus.
    • Characteristics of offspring derived from conventional and X-sorted bovine sperm

      Maicas, C.; Hutchinson, I.A.; Cromie, A.R.; Lonergan, P.; Butler, Stephen; Teagasc Walsh Fellowship Programme (American Dairy Science Association, 2020-08)
      The objective of this retrospective study was to compare survival during the first year of life and adult performance of offspring derived from artificial insemination (AI) with X-sorted or conventional sperm processed from the same ejaculates. We analyzed a data set that included AI of dairy heifers and lactating cows with fresh conventional sperm (3 × 106 sperm per straw), fresh X-sorted sperm (1 or 2 × 106 sperm per straw), or frozen X-sorted sperm (2 × 106 sperm per straw). The data set contained records of 5,179 offspring born on 396 farms. Offspring were classified as born from conventional sperm (CONV) if they were the product of an insemination with fresh conventional sperm, or born from X-sorted sperm (SS) if they were product of any of the 3 X-sorted sperm treatments. Generalized linear mixed models were used to evaluate the effect of sperm treatment on (1) survival during the first year of life; (2) reproductive performance, lactation performance, and survival of female offspring; and (3) slaughter characteristics of male offspring. Stillbirth rates and mortality rates during the first 2 mo of life were greater for male calves (2.8 and 5.0%, respectively) than for female calves (1.6 and 2.0%, respectively). No differences between offspring derived from SS and CONV were detected for incidences of stillbirth or mortality during the first 12 mo of life within sex of calf. Reproductive performance, milk volume, milk fat, milk protein yields during first; second; and third lactations, and survival to third lactation did not differ between female offspring derived from CONV and SS. Across all age groups, CONV steers had heavier carcasses than SS steers (325.3 vs. 318.3 kg), but there were no differences in weight between CONV and SS steers within any of the age groups (≤24, 25–27, 28–30, and >30 mo of age). The distribution of slaughter age did not differ between CONV and SS steers when the analysis was restricted to herds that reared steers derived from both types of sperm. Carcass conformation and fat scores of steers were not affected by sperm treatment. There was no difference in carcass weight between young bulls (≤2 yr) derived from CONV or SS. In conclusion, the results provide no evidence of differences in survival during the first year of life between offspring derived from CONV or SS, or for any of the reproductive and lactation performance characteristics studied between female offspring derived from CONV or SS. Modest differences in carcass weight between CONV and SS steers were detected, but this may reflect differences in management and husbandry in the rearing herds rather than the sex-sorting process. A controlled study using steers derived from conventional or X-sorted sperm from split ejaculates and reared under the same husbandry conditions is needed to clarify whether there is a true difference in body weight gain due to the sex-sorting process.
    • Stability of powdered infant formula during secondary shelf-life and domestic practices

      Condurso, Concetta; Cincotta, Fabrizio; Merlino, Maria; STANTON, CATHERINE; Verzera, Antonella; Italian Ministry for Education, University and Research (MIUR); AIM 1823923-3; CUP J44I18000190006 (Elsevier BV, 2020-10)
      Powdered infant formula (PIF) and lactose-free PIF during secondary shelf-life (SSL) and under domestic practices was investigated to verify their stability up to the expiration date and under the label instructions for milk reconstitution. Particular attention was given to variations in Maillard reaction and lipid peroxidation products identified and quantified by HS-SPME-GC-MS. Two types of PIF: Type A based on bovine milk and Type B a lactose-free product based on glucose syrup were analysed. The PIF were analysed at regular time intervals beyond the labelled expiration date after opening, and reconstituted using water at 70 °C, 80 °C and 90 °C. A large number of volatile compounds were identified and significant statistically differences resulted during SSL and water temperature used for reconstitution that were correlated to the PIF composition. The study showed that water temperature for reconstitution of samples and the SSL has to be adapted to PIF composition.
    • Variability in greenhouse gas emission intensity of semi-intensive suckler cow beef production systems

      Samsonstuen, Stine; Åby, Bente A.; Crosson, Paul; Beauchemin, Karen A.; Wetlesen, Marit S.; Bonesmo, Helge; Aass, Laila; Norwegian University of Life Sciences and Department of Animal and Aquacultural Sciences; The Agriculture and Food Industry Research Funds; Geno Breeding and AI Association; et al. (Elsevier BV, 2020-09)
      Emission intensities from beef production vary both among production systems (countries) and farms within a country depending upon use of natural resources and management practices. A whole-farm model developed for Norwegian suckler cow herds, HolosNorBeef, was used to estimate GHG emissions from 27 commercial beef farms in Norway with Angus, Hereford, and Charolais cattle. HolosNorBeef considers direct emissions of methane (CH4), nitrous oxide (N2O) and carbon dioxide (CO2) from on-farm livestock production and indirect N2O and CO2 emissions associated with inputs used on the farm. The corresponding soil carbon (C) emissions are estimated using the Introductory Carbon Balance Model (ICBM). The farms were distributed across Norway with varying climate and natural resource bases. The estimated emission intensities ranged from 22.5 to 45.2 kg CO2 equivalents (eq) (kg carcass)−1. Enteric CH4 was the largest source, accounting for 44% of the total GHG emissions on average, dependent on dry matter intake (DMI). Soil C was the largest source of variation between individual farms and accounted for 6% of the emissions on average. Variation in GHG intensity among farms was reduced and farms within region East, Mid and North re-ranked in terms of emission intensities when soil C was excluded. Ignoring soil C, estimated emission intensities ranged from 21.5 to 34.1 kg CO2 eq (kg carcass)−1. High C loss from farms with high initial soil organic carbon (SOC) content warrants further examination of the C balance of permanent grasslands as a potential mitigation option for beef production systems.
    • Quality indices and sensory attributes of beef from steers offered grass silage and a concentrate supplemented with dried citrus pulp

      Salami, Saheed A.; O'Grady, Michael N.; Luciano, Giuseppe; Priolo, Alessandro; McGee, Mark; Moloney, Aidan P.; Kerry, Joseph P.; European Union; Department of Agriculture, Food and the Marine; 11/S/122, FEFAN (Elsevier BV, 2020-10)
      This study investigated the quality composition, oxidative stability and sensory attributes of beef (longissimus thoracis, LT) from steers offered grass silage and a concentrate supplement in which barley was replaced by 40% and 80% (as-fed basis) of dried citrus pulp (DCP). Dietary treatment did not influence the antioxidant status (α-tocopherol and total phenolic contents) and activities of LT (radical scavenging activity, ferric reducing antioxidant power and iron chelating activity). Feeding DCP significantly increased the proportion of conjugated linoleic acids and polyunsaturated fatty acids in beef. Lipid and colour stability of fresh beef patties stored in modified atmosphere packs (MAP) were unaffected by dietary treatment but feeding 40% DCP reduced (P < .05) lipid oxidation in aerobically-stored cooked beef patties. Beef patties stored in MAP for up to 7 days were assessed by sensory panellists to be juicier for those fed 40% DCP compared to 0% and 80% DCP. Results indicated that substitution of barley with DCP improved the fatty acid profiles of beef without negatively influencing the eating quality of beef.
    • Effect of thermoresistant protease of Pseudomonas fluorescens on rennet coagulation properties and proteolysis of milk

      Paludetti, Lizandra F.; Kelly, Alan L.; Gleeson, David; Teagasc Walsh Fellowship Program; Dairy Levy project (American Dairy Science Association, 2020-05)
      This study aimed to investigate the effect of different activity levels of a thermoresistant protease, produced by Pseudomonas fluorescens (ATCC 17556), on the cheesemaking properties of milk and proteolysis levels. Sterilized reconstituted skim milk powder was inoculated with the bacteria, and after incubation, centrifuged to obtain a supernatant-containing protease. Raw milk was collected and inoculated to obtain a protease activity of 0.15, 0.60, and 1.5 U/L of milk (treatments P1, P4, and P10, respectively). One sample was not inoculated (control) and noninoculated supernatant was added to a fifth sample to be used as a negative control. Samples were stored at 4°C for 72 h. After 0, 48, and 72 h, the rennet coagulation properties and proteolysis levels were assessed. The protease produced was thermoresistant, as no significant differences were observed in the activity in the pasteurized (72°C for 15 s) and nonpasteurized supernatants. The chromatograms and electrophoretograms indicated that the protease preferably hydrolyzed κ-casein and β-casein, and levels of proteolysis increased with added protease activity over storage time. The hydrolysis of αS-caseins and major whey proteins increased considerably in P10 milk samples. At 0 h, the increase in the level of protease activity decreased the rennet coagulation time (RCT, min) of the samples, possibly due to synergistic proteolysis of κ-casein into para-κ-casein. However, over prolonged storage, hydrolysis of β-casein and αS-casein increased in P4 and P10 samples. The RCT of P4 samples increased over time and the coagulum became softer, whereas P10 samples did not coagulate after 48 h of storage. In contrast, the RCT of P1 samples decreased over time and a firmer coagulum was obtained, possibly due to a lower rate of hydrolysis of β-casein and αS-casein. Increased levels of protease could result in further hydrolysis of caseins, affecting the processability of milk over storage time.
    • An economic comparison of pasture-based production systems differing in sward type and cow genotype

      McClearn, B.; Shalloo, L.; Gilliland, T.J.; Coughlan, F.; McCarthy, B.; Dairy Research Ireland; Teagasc Walsh Fellowship Programme (American Dairy Science Association, 2020-05)
      The objective of this study was to compare the economic performance of 2 sward types [perennial ryegrass (PRG; Lolium perenne L.) sown with or without white clover (Trifolium repens L.)] grazed by 3 cow genotypes. Physical performance data were collected from a 4-yr systems experiment based at Clonakilty Agricultural College, Clonakilty, Co. Cork, Ireland. The experiment compared 2 sward types (PRG-only swards and PRG–white clover swards), with each sward type being grazed by cows from 3 genotypes [Holstein-Friesian (HF), Jersey × HF (JEX), and Norwegian Red × JEX (3-way)]. All systems were stocked at 2.75 cows/ha with fixed fertilizer applications and concentrate supplementation. The data supplied 6 production systems (2 sward types × 3 cow genotypes). The production systems were modeled using the Moorepark Dairy Systems Model (stochastic budgetary simulation model) under 2 scenarios, one in which land area was fixed and one in which cow numbers were fixed. The analysis was completed across a range of milk prices, calf prices, and reseeding programs. The analysis showed that in the fixed-land scenario with a milk price of €0.29/L, adding white clover to PRG swards increased profitability by €305/ha. In the same fixed-land scenario, JEX cows were most profitable (€2,606/ha), followed by 3-way (€2,492/ha) and HF (€2,468/ha) cows. In the fixed-cow scenario, net profit per cow was €128 greater for PRG–white clover swards compared with PRG-only swards. In this scenario, JEX was the most profitable per cow (€877), followed by HF (€855) and 3-way (€831). The system that produced the highest net profit was JEX cows grazing PRG–white clover swards (€2,751/ha). Regardless of reseeding frequency or variations in calf value, JEX cows grazing PRG–white clover swards consistently produced the highest net profit per hectare.
    • Effect of dietary inclusion of benzoic acid (VevoVitall®) on the microbial quality of liquid feed and the growth and carcass quality of grow-finisher pigs

      O’ Meara, F.M.; Gardiner, G.E.; O’ Doherty, J.V.; Lawlor, P.G.; Lawlor, Peadar; Teagasc Walsh Scholarship Programme (Elsevier BV, 2020-07)
      Benzoic acid has long been used as a food preservative due to its antibacterial and antifungal effects. Supplementation to pig diets has also been shown to inhibit microbial free amino acid degradation and to control yeast growth in fermented liquid feed. However, the effect of dietary inclusion of benzoic acid (BA) in fresh liquid feed for grow-finisher pigs on feed quality and the resultant effects on pig growth remain unclear. The objective of the current study was to compare four inclusion levels of BA (VevoVitall®) on feed microbial quality and on the growth performance of grow-finisher pigs. Two-hundred and sixteen pigs with a starting weight of 30.0kg (± 7.43 SD) were used in the experiment. The four dietary treatments were as follows: (1) Basal diet + 0kg/t BA (0kg/t BA), (2) Basal diet + 2.5kg/t BA (2.5kg/t BA), (3) Basal diet + 5kg/t BA (5kg/t BA), (4) Basal diet + 10kg/t BA (10kg/t BA). Lactic acid bacteria (LAB) counts in the mixing tank were similar across treatments (P>0.05) but were lower in the troughs for the feed supplemented with 10kg/t BA than for all other treatments (P<0.01). The pH of the 10kg/t BA treatment was also lower than that of the other three treatments. However, this only occurred in the mixing tank (P<0.01), as in the trough, the basal diet had the lowest pH (lower than the other three treatments; P<0.01). Dietary BA inclusion did not affect average daily gain, average daily feed intake, feed conversion efficiency, final live-weight, carcass weight or carcass quality during the experimental period (P>0.05). In conclusion, while BA may limit the growth of LAB in liquid feed and stabilise feed pH, its inclusion in the diet did not improve the growth performance or carcass quality of grow-finisher pigs.