Equine Production Research Articles

Assessment of fecal bacterial viability and diversity in fresh and frozen fecal microbiota transplant (FMT) product in horses

BackgroundCurrently, lack of standardization for fecal microbiota transplantation (FMT) in equine practice has resulted in highly variable techniques, and there is no data on the bacterial metabolic activity or viability of the administered product. The objectives of this study were to compare the total and potentially metabolically active bacterial populations in equine FMT, and assess the effect of different frozen storage times, buffers, and temperatures on an equine FMT product. Fresh feces collected from three healthy adult horses was subjected to different storage methods. This included different preservation solutions (saline plus glycerol or saline only), temperature (-20 °C or -80 °C), and time (fresh, 30, 60, or 90 days). Samples underwent DNA extraction to assess total bacterial populations (both live and dead combined) and RNA extraction followed by reverse transcription to cDNA as a proxy to assess viable bacteria, then 16s rRNA gene amplicon sequencing using the V1-V2 region.ResultsThe largest difference in population indices and taxonomic composition at the genus level was seen when evaluating the results of DNA-based (total) and cDNA-based (potentially metabolically active) extraction method. At the community level, alpha diversity (observed species, Shannon diversity) was significantly decreased in frozen samples for DNA-based analysis (P < 0.05), with less difference seen for cDNA-based sequencing. Using DNA-based analysis, length of storage had a significant impact (P < 0.05) on the bacterial community profiles. For potentially metabolically active populations, storage overall had less of an effect on the bacterial community composition, with a significant effect of buffer (P < 0.05). Individual horse had the most significant effect within both DNA and cDNA bacterial communities.ConclusionsFrozen storage of equine FMT material can preserve potentially metabolically active bacteria of the equine fecal microbiome, with saline plus glycerol preservation more effective than saline alone. Larger studies are needed to determine if these findings apply to other individual horses. The ability to freeze FMT material for use in equine patients could allow for easier clinical use of fecal transplant in horses with disturbances in their intestinal microbiome.

Use of quantitative mass spectrometry-based proteomics and ELISA to compare the alpha 2 macroglobulin concentration in equine blood-based products processed by three different orthobiologic devices.

Alpha 2 macroglobulin (A2M), a multi-functional protein in the plasma protease inhibitor class, regulates proinflammatory cytokines and the clearance of chondrodestructive enzymes in cases of joint injury and osteoarthritis (OA). The purpose of this study was to compare A2M concentrations in equine plasma samples processed by three commercial devices developed for stall-side regenerative joint therapy. Plasma samples were obtained from healthy adult horses (N = 13). Mass spectrometry analysis was used to determine the concentration of protein analytes in each sample. Selected reaction monitoring measured a specific A2M peptide as a surrogate of the whole A2M protein. A2M concentrations produced by each test device were compared for two sample types: a pre-concentrate or platelet-poor (PP) component and a final component for use in the horse. There was no significant difference (p > 0.05) in the geometric mean (GM) concentration of A2M in the final concentration samples produced by the Alpha2EQ® device (N horses = 13) and the single-centrifugation PP samples produced by the Pro-Stride® APS (autologous protein solution) device (N = 13) and the Restigen® PRP (platelet-rich plasma) device (N = 11). When A2M content in final concentration samples produced by each device was compared, the Pro-Stride APS and Restigen PRP samples had significantly greater GM A2M content (p < 0.0001) compared to the Alpha2EQ samples, and the Pro-Stride APS final concentration samples had significantly greater GM A2M concentration (p < 0.0001) versus that for the Restigen PRP final samples. This comparison demonstrated that the volume and A2M concentration of an Alpha2EQ final concentrate are no different than the volume and concentration of A2M in the PP from Pro-Stride or Restigen devices.

Topical blood products modulate the effects of ophthalmic antibiotics against common bacterial pathogens in dogs with infectious keratitis.

Bacterial keratitis is a common and serious condition that often leads to vision impairment and potential loss of the eye if not treated promptly and adequately. Topical blood products are often used concurrently with topical antibiotics, helping to mitigate corneal 'melt' from proteases released on the ocular surface. However, blood products are rich in albumin and could affect the efficacy of antibiotics due to drug-protein binding. In this study, serum and plasma samples were harvested from 10 healthy dogs and 10 healthy horses, obtaining fresh and frozen (1 month at -20°C) aliquots for in vitro experiments. Albumin levels were quantified using species-specific ELISA kits. Thirty bacteria (10 Staphylococcus pseudintermedius, 10 Streptococcus canis, 10 Pseudomonas aeruginosa), isolated from canine patients with infectious keratitis, were each tested with blank plates as well as commercial susceptibility plates (Sensititre™ JOEYE2) to assess the minimal inhibitory concentration (MIC) of 17 different antibiotics in the absence (control) or presence of eight test groups: serum or plasma (fresh or frozen) from canines or equines. Albumin concentrations ranged from 13.8-14.6 mg/mL and 25.9-26.5 mg/mL in canine and equine blood products, respectively. A direct antimicrobial effect was observed mostly with equine vs. canine blood products (specifically serum and to a lesser degree plasma), and mostly for Staphylococcus pseudintermedius isolates. MICs generally increased in the presence of blood products (up to 10.8-fold), although MICs also decreased (down to 0.25-fold) for selected antibiotics and ocular pathogens. Median (range) fold changes in MICs were significantly greater (p = 0.004) with the canine blood products [2 (0.67-8.1)] than the equine blood products [2 (0.5-5)]. In practice, clinicians should consider equine over canine blood products (lesser impact on antimicrobial susceptibility), serum over plasma (greater antimicrobial effects), and administering the blood product ≥15 min following the last antibiotic eyedrop to minimize the amount of albumin-antibiotic binding in tear film.

Maintaining traditional values and looking for novel uses assure equines' survival as a species

SummaryBackgroundRoutine tasks performed by equids have been taken over by motorised transportation and agricultural mechanisation services, and both are rapidly expanding in developing nations. For instance, in developing nations, the length of all‐season roads annually has increased by 0.2% and the number of vehicles by 15% to 17%. Consequently, rural agriculture no longer regularly recruits equines.ObjectivesStrategies need to be developed to safeguard the use values of equids to guarantee their crucial role in the daily lives of rural people.Study designThe report has compiled the findings of field‐based exploratory qualitative study.MethodsThis study involved in‐depth interviews of 10 knowledgeable informants and analysed FAOSTAT historical dataset to assess the population status of equids.ResultsTo encourage people to use equids for companionship and recreational purposes, the hobbies of equine farming need to be promoted in both urban and rural areas. Equestrian riding and racing can be beneficial for festivals and sociocultural events, like weddings, funerals and competitions. It is illogical to disregard the transportation, ploughing and crop harvesting roles of equids. It is worthwhile to include donkeys and mules in the well‐established sports of horseracing and riding. Bovines can produce high‐quality carcasses when equids are used as work animals. Equine manure is rich in nutrients compared with ruminant manure. Equid meat is occasionally consumed and exported. Equid hides can be used to produce leather goods and parchments. It is essential to investigate the medicinal value of equine products. By clipping hair from horses' tails and manes, handicraft people can make whiskers and cords of musical instruments. Equids are highly sought‐after in landscape management and scientific studies. In rangelands, horses can assist in monitoring grazing and browsing livestock. In open urban public spaces and rural areas, equines can graze on communal grazing lands as stray animals and a population of feral animals may eventually emerge.Main limitationsThis is an exploratory qualitative study and it needs to be supported by extensive studies involving formal surveys.ConclusionTo ensure the continued existence of equids, it is worthwhile to explore the derived use values, enhance the existing ones and alleviate their major production constraints.

Effect of pre-maturation oocyte timing on equine ICSI embryo development rates

Within the last 5 years, client adoption of ovum-pick-up (OPU) paired with equine intracytoplasmic sperm injection (ICSI) and in vitro embryo production (IVP) in Brazil has been rapid. Equine ICSI has facilitated the use of expensive semen be it imported, rare, poor-quality or low motility for IVP. A pre-maturation step occurs between OPU on the farm and transport to the lab. Oocytes are kept in 5 ml vials of pre-maturation medium, held at 22°C until placement in maturation medium. Oocytes in pre-maturation medium are kept at this low temperature to inhibit the onset of germinal vesicle breakdown and the onset of oocyte maturation. If maturation begins during transport, oocyte maturation rates and oocyte quality would be severely reduced. Recently, (Merlo, B et al 2022 Anim Reprod Sci 107071) reported different rates of equine ICSI embryo development based on timing of oocyte pre-maturation and maturation. In our IVP system, oocyte maturation time is tightly controlled between 28 and 32 hours, so we decided to evaluatethe timing of pre-maturation since it can vary between 0 and 24 hours. This variation is based on the time required for OPU completion by multiple teams, aspirating on the same day in different locations. We tested the potential impact of oocyte pre-maturation in 3-time intervals 0-8, 9-16 and 17-24 hours, in the 2021-2022 breeding season. The average blastocyst formation rate based on total oocytes collected was 17%. Embryo development from oocytes aspirated in the 3 pre-maturation time intervals was: 0-8 hours, 522 embryos produced from 3413 oocytes aspirated (15.3%); 9-16 hours, 471 embryos produced from 2667 oocytes aspirated (17.7%) and 17-24 hours, 3931 embryos produced from 22,896 oocytes aspirated (17.2%). There were no significant differences observed (Mann-Whitney test p >0.05), demonstrating that up to 24 hours, the holding time of pre-maturation oocytes, held at 22.5°C had no significant impact on embryo development in our equine ICSI embryo production system.

Characterization of lyophilized equine colostrum

Colostrum is the first milk secretion at birth and is indispensable for the equine newborn. In addition to being the only natural source of immunoglobulins (Igs) available, it has excellent nutritional importance in helping the gastrointestinal system's maturation. Thus, foals need to ingest maternal colostrum in the first hours of life to acquire immunity so that failure of passive transfer of immunity (FPTI) does not occur. The quality of the colostrum supplied to the animals must be evaluated, and innovation in its storage methods would greatly benefit management. Lyophilization is a differentiated process of dehydration that retains a large concentration of colostrum immunoglobulins. The only lyophilized colostrum for foals is based on bovine colostrum) This study aimed to compare the IgG concentration and the physicochemical characteristics of frozen equine colostrum after the lyophilization process. Thirty-one pregnant mares were used. Colostrum samples were collected manually from both mammary glands immediately after delivery. The udder was cleaned with 70% alcohol solution to avoid sample contamination. About 20 mL of colostrum were collected, and the first two jets were discarded. The IgG concentration of frozen and lyophilized colostrum was determined by the Simple Radial Immunodiffusion method (IDRS) and also, indirectly, by Brix refractometry. The samples' physical-chemical composition (pH, total protein (TP),fat, lactose, salts, total solids (TS), and density) was evaluated,and the lyophilized colostrum reconstitution test was performed. The ways of preserving colostrum were compared using a t-test at 5% probability. Pearson correlations were utilized between variables with Sisvar®, version 5.7 statistical software. No significant differences were seen in the measurements of IgG, fat, lactose, salts, TS, density, and pH before and after lyophilization. No difference was seen in the IgG concentration measured by IDRS (frozen 30.5 g/L vs lyophilized 28.5 g/L). A strong positive correlation was observed between colostrum density and IgG concentration by IDRS (r = 0.76) and between Brix and IgG concentration by IDRS (r= 0.77). In the reconstitution test, lyophilized colostrum was efficiently rehydrated in water, with total dilution, and remained stable. The results suggest that lyophilization can be an alternative for conservation of colostrum from mares, because it is a very efficient process for the retention of the physicochemical characteristics of the product, with no significant loss of IgG concentration. In addition, it is easy to reconstitute, can be preserved for a long period without the need for refrigeration and easily transported. This research should be expanded to make an innovative equine product available. This will facilitate the management of newborn foals and help to reduce the rates of failure of passive immunity transfer.

Screening for In Vitro Antibacterial Activity of Leaves Extracts of Certain Selected Plants against Rhodococcus equi

In the present study, the research work was carried out during June 2018 to March 2019 at ICAR-NRCE-EPC (Indian Council of Agricultural Research, National Research Centre on Equines, Equine Production Campus), Jorbeer, Bikaner (Rajasthan), India. The study was conducted to investigate in vitro antibacterial activity of ethanolic, chloroformic and Sequentially Extracted Water Extract (SEWE) leaves extracts of Aegle marmelos, Morus alba, Nerium indicum, Cascabela thevetia (L.) Lippold, Plumeria alba L. and Azadirachta indica against Vap A and Vap C positive Rhodococcus equi. Fresh leaves of these plants were collected manually from campus of ICAR-NRCE-EPC, Jorbeer, Bikaner (Rajasthan). In initial screening ethanolic leaves extract of these plants except Azadirachta indica, were found non-active against Rhodococcus equi. Chloroformic leaves extracts of Azadirachta indica did not showed in vitro antibacterial activity against Rhodococcus equi. While ethanolic and Sequentially Extracted Water Extract (SEWE) leaves extracts of Azadirachta indica showed good in vitro antibacterial activity against Rhodococcus equi. Further, solvent based fractionation, Ethanol Soluble Fraction (ESF), Methanol Soluble Fraction (MSF) and Water Soluble Fraction (WSF) of polar compounds of SEWE did not showed in vitro antibacterial activity against Rhodococcus equi. On comparison with currently used antibiotics (azithromycin and rifampicin), required concentration of the leaves extract of Azadirachta indica was too high for their possibilities of in vivo use, so abundant availability of Azadirachta indica leaves and their activity against Rhodococcus equi suggests their potential for use as disinfectant against Rhodococcus equi.

A Three-Monoclonal Antibody Combination Potently Neutralizes BoNT/G Toxin in Mice.

Equine-derived antitoxin (BAT®) is the only treatment for botulism from botulinum neurotoxin serotype G (BoNT/G). BAT® is a foreign protein with potentially severe adverse effects and is not renewable. To develop a safe, more potent, and renewable antitoxin, humanized monoclonal antibodies (mAbs) were generated. Yeast displayed single chain Fv (scFv) libraries were prepared from mice immunized with BoNT/G and BoNT/G domains and screened with BoNT/G using fluorescence-activated cell sorting (FACS). Fourteen scFv-binding BoNT/G were isolated with KD values ranging from 3.86 nM to 103 nM (median KD 20.9 nM). Five mAb-binding non-overlapping epitopes were humanized and affinity matured to create antibodies hu6G6.2, hu6G7.2, hu6G9.1, hu6G10, and hu6G11.2, with IgG KD values ranging from 51 pM to 8 pM. Three IgG combinations completely protected mice challenged with 10,000 LD50s of BoNT/G at a total mAb dose of 6.25 μg per mouse. The mAb combinations have the potential for use in the diagnosis and treatment of botulism due to serotype G and, along with antibody combinations to BoNT/A, B, C, D, E, and F, provide the basis for a fully recombinant heptavalent botulinum antitoxin to replace the legacy equine product.

The effects of obesity and insulin dysregulation on mare reproduction, pregnancy, and foal health: a review.

Obesity is a growing welfare concern in modern equine populations and predisposes horses to disturbances in energy metabolism such as insulin dysregulation. However, equine metabolic syndrome has only been recognized in recent decades. Functioning energy metabolism is pivotal to normal body homeostasis and affects essentially all organ systems, including reproduction. Previous literature suggests that obesity has an effect not only on the reproductive processes in mares but also on offspring health, predisposing the offspring to later-onset orthopedic and metabolic problems. This review focuses on the effects of obesity, insulin dysregulation and hyperinsulinemia on the reproductive functions of mares and the implications on foal health before and after birth. The points of interest are the cyclicity and ovarian function, uterine environment, gestation, the postpartum period, and the newborn foal. The aim is to review the current state of knowledge, and identify outstanding questions that could stimulate future research. This topic is important not only from the equine industry and production perspective but is also relevant for the welfare of future populations and individuals.

Synthesis and Clinical Examination of Novel Formulations of Ivermectin, Albendazole and Niclosamide for the Treatment of Equine Gastrointestinal Helminthoses.

This study aimed to develop new complex preparations of ivermectin, niclosamide and albendazole based on solid-phase mechanochemical technology, and to evaluate their efficacy against equine nematodosis and cestodosis. Novel formulation of antiparasitic paste were prepared using joint mechano-chemical treatment of ivermectin (0.2 mg/kg bodyweight; BW), niclosamide (10 mg/kg BW) and albendazole (3, 5, 10 mg/kg BW) substances with polyvinylpyrrolidone and arabinogalactan. For the evaluation of activity of different doses of formulations against gastrointestinal tract helminths a total of 151 adult horses of the Novoaltai breed weighing 450-500 kg naturally infected with strongyles (>150 egg per gram of faeces, EPG), Parascaris spp. (>20 EPG) and Anoplocephala spp. (>10 EPG) were selected. Antiparasitic pastes were orally fed to the horses and faecal egg count reduction counts were compared prior to and 14 days after the treatment. Pastes with mechanically modified ivermectin showed 91.4-100% efficacy against strongyles and Parascaris. Pastes with modified albendazole and niclosamide were also effective against Anoplocephala in all tested dosages i.e. 78.6-100%. In particular, treatment with two formulations containing i) 0.2 mg ivermectin, 10 mg albendazole, 10 mg niclosamide, and ii) 0.2 mg ivermectin, 3 mg albendazole showed 100% efficacy against strongyles, Parascaris and Anoplocephala. Solid-phase mechanochemical technology could be applied in equine anthelminthics production. It is suggested that future studies focus on plasma concentration-time profile of these highly effective pastes.

Commercial equine production in New Zealand 4: welfare implications of the New Zealand production systems

From racehorses to family pets, equine production and management is primarily pasture-based in New Zealand. Pasture-based equine production systems largely reflect the horse’s ecological niche and have a unique set of management and welfare challenges. This review examines the potential welfare issues related to the management of horses in New Zealand. The economic value of horses varies greatly depending on their usage, which covers a wide spectrum from pest species (e.g. feral horses) to production (e.g. racehorses) and companion animals (e.g. leisure and sport horses). The view of where the horse is positioned on this spectrum may cause differing welfare threats to horses, due to the economic considerations, which drive the majority of welfare and managemental decisions. The organisation, management, racing and wastage metrics of the Thoroughbred racehorse industry are well documented, and the benefits of the pasture-based system have become evident through less stressful weaning practices and opportunity for early exercise (which has been associated with longer careers and fewer musculoskeletal injuries). Identification of equine-welfare research priorities in New Zealand remains challenging, given the lack of vertical integration of many sectors of the equine industry resulting in fragmented and limited availability of data.

Sero-epidemilogical survey of dourine T. Equiperdum in Chencha district of southern region

The study was conducted in Gamo highland, chencha district with an objective to determine the prevalence rate and associated risk factors of the disease. For this study, four villages were selected with high potential of equine. On clinical examination, there were cases with clinical signs of dourine (oedema on the lower abdomen and swelling of testicles and vagina). 32 horses of adult age were examined. Both parasitological (buffer coat technique) and serological tests were conducted. Out of examined horses, there were no findings for parasitological technique, whereas, 5 were sero-posetive for trypanosome antibodies). The study showed a prevalence rate of 15.6% of the disease in the study area. Major constraints that hampered equine production in the study area other than the diseases were feed shortage and poor veterinary service. A disease with clinical sign of dourine was an outstanding disease affecting equine production and productivity in the study area. Therefore, an awareness creation has to be done for development agents and farmers on clinical signs and means of transmission and options of control and prevention of the disease to control further transmission to equine population.

Soroepidemiologia de leptospirose em equinos da região de Santarém, Pará

Abstract Leptospirosis is an endemic zoonotic disease that is distributed worldwide, which has the potential to have health and economic impacts. Leptospira spp. is spiral-shaped and capable of infecting mammals, including horses, which may result in asymptomatic or clinical forms. Therefore, the current study aimed to analyze the frequency of anti-Leptospira antibodies in serum samples from horses from Santarém, Pará, Brazil. For that purpose, 88 blood samples from horses without a history of leptospirosis vaccination were serologically evaluated through the microscopic agglutination technique (MAT) with a 13 serovars, belonging to ten different serogroups. There were 58 samples that were seropositive (65.90%), which included 28 samples seropositive for Pyrogenes (48.3%), 24 for Autumnalis (41.4%), 18 for Icterohaemorrhagiae (31.0%), and 16 for Grippotyphosa (27.6%). Even without clinical suspicion of leptospirosis or a history of vaccination, the horses showed different frequency of seropositivity. Considering the well-known impact of leptospirosis in human and animal health, our results are important to establish preventive measures to reduce the economic loss in equine production as well as a reduction in public health risk.

Current status of glanders in Brazil: recent advances and challenges.

Glanders is an infectious disease that causes serious damage to the equine production chain in countries where it occurs endemically and poses a risk to public health. This study aimed to conduct an integrative review of the advances in the knowledge of glanders in Brazil over the last three decades since its re-emergence. Documentary research was conducted for the period between the years 2000 and 2022. SCOPUS and PUBMED databases were used to search for scientific articles, dissertations, and thesis, in addition to the Brazilian Digital Library of Thesis and Dissertations (BDTD). A total of 41 documents were retrieved, including 12 dissertations, five theses, and 24 scientific articles. The Federal Rural University of Pernambuco (UFRPE) group provided a noteworthy amount of material on this topic (25 documents, four theses, three dissertations, and 18 scientific articles). During this period, ten dissertations, one thesis, and six scientific articles published by other groups in other states of the Federation were also identified. It was concluded that there was a significant number of scientific publications with relevant data on the clinical, epidemiological, pathological, microbiological, serological, and molecular characteristics of glanders disease in Brazil. Additionally, training of human resources regarding this disease led to an increase in the nucleation of research groups, especially in the northeast region of Brazil. Despite significant advances, new research groups and specific funding are still needed for the development of more accurate diagnostic methods, immunizing production, training of veterinarians to recognize the disease, and more robust programs to control and eradicate the disease in Brazil.

Direct 14C dating of equine products preserved in archaeological pottery vessels from Botai and Bestamak, Kazakhstan

Direct and accurate radiocarbon dating of lipid residues preserved in ceramics is a recently established method that allows direct dating of specific food products and their inception in human subsistence strategies. The method targets individual fatty acids originating from animal fats such as ruminant dairy, ruminant adipose, non-ruminant adipose and aquatic fats. Horse lipid residues found in Central Asian pottery vessels are also directly dateable using this new method. Here we present the identification of equine lipid residues preserved in two pottery assemblages from the Neolithic and Eneolithic in Kazakhstan and their direct 14C dating. The site of Botai, previously radiocarbon-dated to the 4th millennium BC, was used as a reference to evaluate the dates obtained directly on horse lipids. The direct dating of equine products extracted from Botai potsherds are shown to be compatible with previous 14C dates at the site. The site of Bestamak, lacking previous14C measurements, had been relatively dated to the Neolithic based on pottery typologies. The direct dating of equine residues made it possible to anchor the pottery assemblage of Bestamak in the 6th millennium BC confirming their Neolithic attribution. These findings demonstrate the potential for dating horse products through a compound-specific approach, while highlighting challenges in 14C dating individual fatty acids from lipid extracts in which their abundances differ substantially.

Parascaris equorum in Horses of Payakumbuh City, West Sumatra, Indonesia

Parascaris equorum is a species of the Ascarididae family which belongs to the phylum nematoda (roundworms) and is a type of parasite that affects equine health, performance, and production. The current study was carried out from April to August 2021 to determine the prevalence of equine Parascaris equorum in horses residing in Payakumbuh City, Indonesia. A total number of 128 fecal samples from horses were examined in the current study. Coprological examination was performed for the detection of Parascaris equorum eggs inside the amassed samples. The overall occurrence of Parascaris equorum was 14.06% (18 out of 128). The prevalence rates of sub-districts differed with the highest in East at 18.18% (8/44), followed by North, South, and West at 16.66% (6/36), 14.06% (2/22), and 7.7% (2/26), respectively. The obtained results indicated a significant difference in the prevalence rate of Parascaris equorum between males and females as well as those horses aged &lt; 5 years (26.22%) and &gt; 5 years (3%). Therefore, it is critical to not only enhance horse health management, maintenance, and health but also to provide anti-parasitic medications on a regular basis.

Oocytes obtained by ovum pick-up from live mares as an alternative to abattoir-derived oocytes for the development of equine embryos produced by somatic cell nuclear transfer

The production of equine embryos by somatic cell nuclear transfer (SCNT) is limited by the availability of immature oocytes. The main source of oocytes for SCNT comes from ovaries obtained from slaughter houses. However, in some countries there is no horse abattoirs or their number is limited which precludes the use of SCNT for the production of equine cloned embryos. Ovum pick-up (OPU) is a reproductive assisted technique which is growing rapidly in the equine industry which allows obtaining oocytes from live mares. OPU is mainly used in combination to ICSI (intracytoplasmic sperm injection) for the production of in vitro embryos. Oocytes collected from live recipient mares by OPU could be an alternative for SCNT in countries in which there are limited number of equine slaughter houses. However, it is unknown the effect of the oocytes’ source on the development of equine cloned embryos. The aim of this study was to compare the development of equine SCNT embryos produced using oocytes either retrieved by OPU or recovered from abattoir-sourced ovaries. For the study, a total of 1128 oocytes were used, of which 663 were from abattoir-sourced ovaries and 495 were from live mares programmed for OPU. The harvested ovaries were transported to the lab within 1 h for processing. The methods used for in vitro maturation (IVM), SCNT andembryo culture in vitro were identical for both sources of oocytes. The rates of maturation, cell fusion, cleavage and blastocyst formation at Day 7 were evaluated. Transferrable grade blastocysts were transferred to recipient mares 4 to 5 days after ovulation and pregnancy was diagnosed at Days 14 and 42 by ultrasound. The maturation rate of OPU-derived oocytes was lower than that of abattoir-derived oocytes (50.3 ± 2.7% vs . 61.9 ± 3.4%; P < 0.05). However, the rates of cell fusion (90.7 ± 2.6% vs. 81.9 ± 5.2%), cleavage (68.8 ± 3.9% vs . 61.9 ± 5.0%) and blastocyst formation (34.3 ± 2.8% vs. 25.4 ± 2.1%) were greater (P < 0.05) for OPU-derived embryos compared with abattoir-derived embryos. While similar proportions of OPU- and abattoir-derived blastocysts initiated pregnancy at Day 14, a greater proportion of OPU-derived blastocysts developed to Day 42 of gestation (13 of 50 embryos) compared with abattoir-derived blastocysts (3 of 27 embryos; P < 0.05). The results show that abattoir-sourced oocytes subjected to IVM have the potential to support the development of SCNT embryos that can initiate pregnancy. However, given the observed difference in subsequent in vivo development, the use of OPU-derived oocytes for equine SCNT embryo production is recommended. Further research is needed to improve the IVM of abattoir-sourced oocytes

An allergen-fused dendritic cell-binding peptide enhances in vitro proliferation of equine T-cells and cytokine production

Allergen-specific immunotherapy (AIT) constitutes the only curative approach for allergy treatment. There is need for improvement of AIT in veterinary medicine, such as in horses suffering from insect bite hypersensitivity, an IgE-mediated dermatitis to Culicoides. Dendritic cell (DC)-targeting represents an efficient method to increase antigen immunogenicity. It is studied primarily for its use in improvement of cancer therapy and vaccines, but may also be useful for improving AIT efficacy. Immunomodulators, like the Toll-like receptor 4 (TLR-4) agonist monophosphoryl lipid-A (MPLA) has been shown to enhance the IL-10 response in horses, while CpG-rich oligonucleotides (CpG-ODN), acting as TLR-9 agonists, have been shown to induce Th1 or regulatory responses in horses with equine asthma. Our aim was to evaluate in vitro effects of antigen-targeting to equine DC with an antigen-fused peptide known to target human and mouse DC and investigate whether addition of MPLA or CpG-ODN would further improve the induced immune response with regard to finding optimal conditions for equine AIT. For this purpose, DC-binding peptides were fused to the model antigen ovalbumin (OVA) and to the recombinant Culicoides allergen Cul o3. Effects of DC-binding peptides on cellular antigen uptake and induction of T cell proliferation were assessed. Polarity of the immune response was analysed by quantifying IFN-γ, IL-4, IL-10, IL-17 and IFN-α in supernatants of antigen-stimulated peripheral blood mononuclear cells (PBMC) in presence or absence of adjuvants. Fusion of DC-binding peptides to OVA significantly enhanced antigen-uptake by equine DC. DC primed with DC-binding peptides coupled to OVA or Cul o3 induced a significantly higher T-cell proliferation compared to the corresponding control antigens. PBMC stimulation with DC-binding peptides coupled to Cul o3 elicited a significant increase in the pro-inflammatory cytokines IFN-γ, IL-4, IL-17, as well as the anti-inflammatory IL-10, but not of IFN-α. Adjuvant addition further enhanced the effect of the DC-binding peptides by significantly increasing the production of IFN-γ, IL-4, IL-10 and IFN-α (CpG-ODN) and IL-10 (MPLA), while simultaneously suppressing IFN-γ, IL-4 and IL-17 production (MPLA). Targeting equine DC with allergens fused to DC-binding peptides enhances antigen-uptake and T-cell activation and may be useful in increasing the equine immune response against recombinant antigens. Combination of DC-binding peptide protein fusions with adjuvants is necessary to appropriately skew the resulting immune response, depending on intended use. Combination with MPLA is a promising option for improvement of AIT efficacy in horses, while combination with CpG-ODN increases the effector immune response to recombinant antigens.

Life Cycle Assessment of Water in Sport Equine Production in Argentina: A Case Study

The application of life cycle assessment method (LCA) to animal production is a methodological option to assess the potential impact of products, services, or production processes in a comprehensive way as it considers both the quantity and quality of water in the life cycle approach. In this paper, the water footprint of jumping sport horses’ production has been determined using the LCA methodology for the first time ever. The results of this paper show that the production of medium- and high-performance sport horses uses a large amount of water. However, modifications to the diet (type and percentage of oils in the supplement, place of origin of feed, etc.) and in the management and destination of waste (animal box beds) can result in a reduction of the water requirement and the environmental impact of production. This type of studies should be developed in different farms in the future in order to give producers management alternatives that improve the sustainability of productions.

The effect of dietary forages in tetanus hyper immunized equine serum production

The determination of local forage in meeting the nutritional requirement of horses and its effect on the antibody titer production is necessary to be conducted. The aim of the study was to determine the effect of dietary forage to antibody titer production of Anti-Tetanus Serum. All procedures performed in this study were approved by the Institutional Animal Care and Use Committee (Ethical Approval No: 01/IACUC-BF/VI/20). A total of 12 Sandalwood horses aged 3-6 years with body weight ranged at 268.4 - 365.8 kg were used in this study. Horses were randomly assigned into four dietary treatment groups for ten weeks (100% Elephant grass; 100% Mott elephant grass; 67% Elephant grass: 33% Kikuyu grass; and 67% Mott elephant grass: 33% Kikuyu grass) which allowed 7.24; 11.45; 11.12; 12.62% crude protein respectively. The titer measurement was carried out once a week during the production period. The data obtained was analyzed using correlation analysis. The results showed that 100% Mott elephant grass group produced the highest titer but the correlation between crude protein levels in the diets and titer were weak (0.44). Thus, it can be concluded that the high protein forage given has no potential to increase the serum antibody titer.