ARTICLE | doi:10.20944/preprints202210.0117.v1
Online: 10 October 2022 (09:56:09 CEST)
Ovine footrot is a complex multifactorial infectious disease, causing lameness in sheep with major welfare and economic consequences. Dichelobacter nodosus is the main causative bacterium, however, footrot is a polymicrobial disease with Fusobacterium necrophorum, Mycoplasma fermentans and Porphyromonas asaccharolytica also associated. There is limited understanding of the host response involved. Proinflammatory mediators interleukin (IL)-1β and C-X-C Motif Chemokine Ligand 8 (CXCL8) have been shown to play a role in the early response to D. nodosus in dermal fibroblasts and interdigital skin explant models. To further understand the response of ovine skin to bacterial stimulation, and to build the understanding of the role of the cytokines and chemokines identified in transcriptomic data, primary ovine interdigital fibroblasts and keratinocytes were isolated, cultured and stimulated with lipopolysaccharide (LPS), D. nodosus or F. necrophorum in the presence and absence of M. fermentans, whilst measuring mRNA expression and protein release of CXCL8 and, IL-1β. Stimulation with LPS, D. nodosus or F. necrophorum resulted in increased transcript levels of IL-1β and CXCL8 in M. fermentans free cells, however, only an increase in CXCL8 protein release was observed. No IL-1β protein release was detected despite increases in IL-1β mRNA, suggesting the signal for intracellular pre-IL-1β processing may be lacking when culturing primary cells in isolation. Keratinocytes and fibroblasts naturally infected with M. fermentans showed little response to LPS, a range of D. nodosus preparations or heat-inactivated F. necrophorum. Primary single cell culture models complement ex vivo organ culture models to study different aspects of the host response to D. nodosus. Ovine keratinocytes and fibroblasts infected with M. fermentans had a reduced response to experimental bacterial stimulation. However, in the case of footrot where Mycoplasma spp. are associated with diseased feet, this natural infection gives important insights into the impact of multiple pathogens on the host response.
ARTICLE | doi:10.20944/preprints202011.0439.v1
Subject: Life Sciences, Biochemistry Keywords: sheep; microsatellite polymorphism; Ovar - MHC; mastitis; lymphocytes
Online: 16 November 2020 (17:31:11 CET)
Udder diseases (mastitis) are a serious cause of economic losses in sheep breeding as they have a negative impact on lamb rearing and the quality of dairy products. So far the progress in treatment and prevention of these diseases has been insufficient, giving ground for searching possibilities of using natural immunity to combat mastitis. The aim of the study was to assess the relationship between the microsatellite polymorphism of selected Ovar-MHC genes and the health status of the mammary gland of sheep. The research was carried out on sheep of the Polish Heath and Polish Lowland breeds. In ovine milk the number of somatic cells (SCC) and the percentage of the lymphocyte subpopulation were assessed. On the basis of genomic DNA, molecular analysis of the Ovar-MHC gene fragments (OLADRB1, OLADRB2, OMHC1) polymorphism was performed. Significant differences were found in SCC and the percentage of lymphocytes (CD4, CD8, CD19) in the milk depending on the alleles of the Ovar-MHC genes. Alleles of 488 bp (DRB1) and 284 bp (DRB2) were found more frequently in sheep with healthy udders, while carriers of the 508 bp (DRB1) and 272 bp (DRB2) alleles were more prone to subclinical mastitis. The obtained results justify the need for further research in order to better understanding the genetic basis of mastistis and to search for effective molecular markers that can be used in breeding practice.
ARTICLE | doi:10.20944/preprints202107.0405.v1
Subject: Life Sciences, Biochemistry Keywords: Sheep; E. coli; shiga-toxin; antimicrobial resistance genes
Online: 19 July 2021 (11:12:01 CEST)
Inappropriate antimicrobial treatment can pose a risk for developing resistance against antimi-crobial drugs in bacteria. Close human contact might have a higher chance of being transmitted to humans from sheep if the sheep population is a potential reservoir of zoonotic pathogens such as shiga toxin-producing Escherichia coli (E. coli) (STEC). Therefore, this study aimed to exam-ine the sheep population in rural Bangladesh for antimicrobial resistant STEC. We screened 200 faecal samples collected from sheep in three Upazila from the Chattogram district. Phenotypical-ly positive E. coli isolates were examined for two shiga toxin-producing genes – stx1 and stx2. PCR positive STEC isolates were investigated for the presence of antimicrobial resistance genes- blaTEM, sul1 and sul2. In total, 123 of the 200 tested samples were confirmed positive E. coli by cul-tured based methods. PCR results show 17(13.8%) E. coli isolates harboured ≥ one virulent gene (stx1 or/and stx2) of STEC. Six of the tested STEC isolates exhibited blaTEM gene; eight STEC isolates had sul1 gene, and sul2 gene was detected in ten STEC isolates. To our knowledge, this study is the first to reveal a significant proportion of STEC isolated from sheep in rural Bangla-desh harbouring antimicrobial resistance genes.
ARTICLE | doi:10.20944/preprints202106.0588.v1
Subject: Life Sciences, Other Keywords: Antimicrobial use; knowledge; farmer-attitude; dairy-farmer; sheep
Online: 23 June 2021 (13:26:05 CEST)
This work examines dairy and sheep farmer attitudes toward antimicrobial use (AMU) in New Zealand. There is increasing public demand on livestock producers to reduce AMU in livestock. The demand stems from concerns about potential antimicrobial resistance (AMR) that could originate from food animals. There is limited practical data on farmer knowledge of AMU. An electronic survey was sent to dairy (n= 378) and sheep farmers (n= 551). Seventy-six dairy farmers (20%, n=76/378) returned the survey. Dairy farmers (69%) showed low levels of concern about antimicrobial resistance and awareness of the need to reduce AMU. Additionally, 76% of dairy farmers didn’t think it was possible to reduce AMU. Thirty-nine sheep farmers (7%, 39/551) returned the survey. 76% of sheep farmers were supportive of restricted use of AMU. The dairy and sheep farmers sourced most of the advice from veterinarians (>90%), the livestock industry (>80%) and their colleagues (>70%). This study shows that farmers showed varied concerns about AMR and AMU. Moreover, sheep farmers were more amenable to increased restriction on AMU than dairy farmers. This study suggests that knowledge gaps in farmers may best be filled by veterinarian input.
REVIEW | doi:10.20944/preprints202101.0425.v1
Subject: Life Sciences, Biochemistry Keywords: Goat; Sheep; Small Ruminants; Animal Models; Regenerative Medicine.
Online: 21 January 2021 (15:01:17 CET)
Medical and translational scientific research requires the use of animal models as an initial approach to the study of new therapies and treatments, but when the objective is an exploration of translational potentialities, classical models fail to adequately mimic problems in humans. Among the larger animal models that have been explored more intensely in recent decades, small ruminants, namely sheep and goats, have emerged as excellent options. The main advantages associated to the use of these animals in research works are related to their anatomy and dimensions very similar to those of humans in most physiological systems, in addition to their low maintenance and feeding costs, tendency to be docile, long life expectancies and few ethical complications raised in society. The most obvious disadvantages are the significant differences in some systems such as the gastrointestinal, and the reduced amount of data that limits the comparison between works and the validation of the characterization essays. Despite everything, recently these species have been increasingly used as animal models for diseases in different systems, and the results obtained open doors for their more frequent and advantageous use in the future. The purpose of this review is to summarize the general principles related to the use of small ruminants as animal models, with focus on regenerative medicine, to group the most relevant works and results published recently and to highlight the potentials for the near future in medical research.
ARTICLE | doi:10.20944/preprints202010.0278.v1
Subject: Biology, Anatomy & Morphology Keywords: sheep; gestation; hemodinamycs; heart rate variability; cardiac output
Online: 13 October 2020 (12:15:51 CEST)
This study aimed at evaluating changes in the clinical and echocardiographic parameters of pregnant sheep, as well as the HRV indexes due to the physiological alterations that happen at this stage implicating in high maternal metabolic demands. For this purpose, the study evaluated 10 Dorper sheep through their pregnancy, starting from the second month until the day before birth, conducting clinical, echocardiographic and electrocardiographic examinations focused on the HRV. The echocardiogram was conducted in a doppler ultrasound device with a multifrequency sectorial transducer in bidimensional mode. The HRV indexes were obtained through the Televet 100® system. There were increases in the thickness of the interventricular septum during diastole starting from the third month, and in the internal diameter of the left ventricle during systole and diastole at the second and third months, while the ejection fraction increased as the pregnancy progressed. The size of the left atrium increased starting at the second month. The SDNN, RMSSD and PNN50 HRV indexes were higher at the fifth month of pregnancy and after delivery. There were no significant differences in the frequency-domain HRV indexes during pregnancy. The gestation leads to alterations in the clinical parameters and the activity of the autonomic nervous system.
ARTICLE | doi:10.20944/preprints201806.0178.v1
Subject: Biology, Animal Sciences & Zoology Keywords: NSAIDs; salicylic acid; sodium salicylate; HPLC; sheep; pharmacokinetics
Online: 12 June 2018 (09:35:41 CEST)
The pharmacokinetics of salicylic acid (SA) in sheep was evaluated following intravenous (IV) and oral administration of sodium salicylate (sodium salt of salicylic acid) at different doses. Six healthy sheep were administered sodium salicylate (SS) IV at doses of 10, 50, 100 and 200 mg/kg body weight and another six sheep were drenched with 100 and 200 mg/kg of SS orally. Both studies were randomised crossover trials. A one-week washout period between each treatment was allowed in both studies. Blood samples were collected at 0, 15, 30 minutes and 1, 2, 4 and 6 hours after IV and oral SS administrations. Plasma SA concentrations were determined using high performance liquid chromatography with diode array detection method. Pharmacokinetic variables were calculated in a non-compartmental model. The elimination half-life (T1/2 el) of SA after IV administration of 200 mg/kg SS was 1.16 ± 0.32 hours. Mean bioavailability of SA was 64%, and mean T1/2 el was 1.90 ± 0.35 hours, after 200 mg/kg of oral SS. The minimum plasma SA concentration (16.8 µg/mL) required to produce analgesia in humans was achieved after IV administration of 100 and 200 mg/kg SS in sheep for about 0.17 hour in this study. Experiments on pharmacokinetic-pharmacodynamics modelling are required to determine the actual effective plasma concentration range of SA in sheep.
ARTICLE | doi:10.20944/preprints202107.0061.v1
Subject: Life Sciences, Biochemistry Keywords: Sheep breeds; Awassi; Najdi; Harri; Growing; Digestibility; Nitrogen retention
Online: 2 July 2021 (14:19:29 CEST)
Forty-five of intact three sheep breeds (Awassi, Harri, and Najdi) were used in this study (15 animals of each breed), with weight ranged from 23.40 to 25.87 kg. Five animals from each group at the end of growth trial were used for digestibility and nitrogen balance trials. The three groups of sheep had effect (p > 0.05) in the final live weight (FLW). Average daily feed intake (ADI), average daily gain (ADG) and feed conversion ratio (FCR) were significantly (p < 0.05) different among the three groups. For digestibility coefficients, the three breeds of sheep had no effect (p > 0.05) in dry matter (DM), organic matter (OM), crude protein (CP), crude fiber (CF), nitrogen free extract (NFE), neutral detergent fiber (NDF) and acid detergent fiber (ADF). In the similar approach, no significant differences were founds among three breeds of sheep in digestible organic matter, digestible of crude protein, total digestible nutrients and nitrogen retention. The current study concluded that the sheep breeds affected average daily feed intake, average daily gain and feed conversion ratio (FCR). Awassi breed showed the best of average daily gain and feed conversion ratio followed by Najdi then Harri breeds. The breed of sheep had no effect on digestibility coefficients and nitrogen retention.
COMMUNICATION | doi:10.20944/preprints202105.0380.v1
Subject: Biology, Anatomy & Morphology Keywords: Analgesia; local anesthetic; sheep; lignocaine; elastrator; husbandry; rubber ring
Online: 17 May 2021 (10:03:53 CEST)
Use of local anesthesia at the time of ring castration and tail docking can improve lamb welfare. However, few local anesthetics are registered for sheep, and data on their duration of effect is limited. Three studies were conducted to evaluate the efficacy of procaine (P), lidocaine (L) and bupivacaine (B) in terms of observed alleviation of behavioral responses to castration and/or tail docking in 10-min blocks in the first 60 min post treatment. In each study, comparisons were made between two groups of lambs castrated and/or tail docked with rubber rings and either receiving the agent using the NUMNUTS® instrument (N) or receiving no anesthetic agent (RR). Acute pain behavior was lower in NL (n = 28) than RRL (n = 15) males in the first 10 min post procedure (P < 0.05); lower in NB (n = 16) than RRB (n = 16) males in periods 10-20 min (0.05 < P < 0.01), 20-30 min (P < 0.05) and 40-50 min (0.05 < P < 0.01); lower in NB (n = 16) than RRB (n = 16) females between 20 and 40 min post-procedure (0.05 < P < 0.01); lower in NP (n = 8) than RRP (n = 7) males in period 10-20 min (0.05 < P < 0.01), and lower in NP (n = 9) than RRP (n = 9) females in periods 0-10 min (0.05 < P < 0.01), and 10-40 min (P < 0.05). Analgesic benefits were modest, and the effects of procaine appear to last longer than lidocaine, while bupivacaine is slower to take effect than either procaine or lidocaine but may provide longer lasting analgesia. The duration of action of local anesthetics is short in sheep, and detailed behavioral evaluations are required in the first hour post procedure to establish efficacy.
ARTICLE | doi:10.20944/preprints202008.0617.v1
Subject: Medicine & Pharmacology, Veterinary Medicine Keywords: refinement; pain; nociceptive threshold; horse; cat; dog; sheep; camel
Online: 27 August 2020 (12:20:22 CEST)
Nociceptive threshold (NT) testing is widely used for the study of pain and its alleviation. The end point is a normal behavioural response which may be affected by restraint or unfamiliar surroundings leading to erroneous data. Remotely controlled thermal and mechanical NT testing systems were developed to allow free movement during testing and were evaluated in cats, dogs, sheep, horses and camels. Thermal threshold (TT) testing incorporated a heater and temperature sensor held against the animal’s shaved skin. Mechanical threshold (MT) testing incorporated a pneumatic actuator attached to a limb containing a 1 - 2mm radiused pin pushed against the skin. Both stimuli were driven from battery powered control units attached on the animal’s back, controlled remotely via infra-red radiation from a hand held component. Threshold reading was held automatically and displayed digitally on the unit. The system was failsafe with a safety cutout at a preset temperature or force as appropriate. The animals accepted the equipment and behaved normally in their home environment enabling recording of reproducible TT (38.5 – 49.8°C) and MT (2.7 – 10.1N); precise values depended on species, the individual and the stimulus characteristics. Remote controlled NT threshold testing appears to be a viable refinement for pain research.
Subject: Medicine & Pharmacology, Allergology Keywords: analgesia; sheep; ischemia; latex ring; rubber ring; de-tailing; behavior.
Online: 1 June 2021 (09:50:27 CEST)
Docking the tail of lambs is a standard husbandry procedure and is achieved through several techniques including clamps, hot or cold knives and latex rings, the last of which is the most popular. All tail docking methods cause acute pain which can be reduced by application of local anesthetic, however precise anatomical injection for optimal efficacy requires considerable skill. This pen trial evaluated the ability of local anesthetic delivered with a dual function ring applicator / injector to alleviate acute tail docking pain. Thirty ewe lambs were assigned to one of three treatment groups (n = 10 per group): ring plus local anesthetic (Ring LA), ring only (Ring) and sham handled control (Sham). Lambs were videoed and behavior categorized every 5 minutes for the first hour and every 10 min for the subsequent 2 hours after treatment. There was a significant effect (p < 0.001) of treatment on total active pain related behaviors in the first hour, with Ring lambs showing higher counts compared to Ring LA or Sham. Ring lambs also displayed a significantly higher count of combined abnormal postures (p < 0.001) than Ring LA or Sham lambs. Delivery of 1.5ml of 2% lignocaine via the dual action device abolished abnormal behaviors and signs of pain in Ring LA lambs. However, lambs in the Ring LA group spent less time attempting to suckle compared to Ring and Sham lambs, suggesting that some residual discomfort remained.
ARTICLE | doi:10.20944/preprints202104.0363.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: compost; high-throughput sequencing; sheep manure; soil properties; crop yield
Online: 14 April 2021 (08:06:52 CEST)
Microbial communities play a key role in sustainable agriculture. However, we still need more in-formation, to understand the complex response of the microbial community to long-term organic farming, which aims to reduce synthetic fertilizer and pesticide use in order to produce sustainably and improve soil quality. We have assessed the long-term effect of two organic cropping systems and a conventional system on the microbial soil community structure using high-throughput se-quencing analysis. We analyzed the link between these communities and changes in soil properties and crop yield. Results showed that the crop yield was similar among the three cropping systems. Soil properties, such as total organic carbon, nitrogen, ammonium, magnesium and boron, influ-enced changes in the bacterial community structure. A linear discriminant analysis effect size (LEfSe) showed different bacteria and fungi as key microorganism of each of the three different cropping systems, in addition, our results reflected that fungal community were more sensitive than bacteria to cropping system. This research provides an insight about changes occurred in soils, especially in microbial communities considering the effect of that changes in crop yield which were remained stable among the different cropping systems.
Subject: Biology, Anatomy & Morphology Keywords: BMP15 gene; Ewe; Sudanese Sheep; Residue; Wild type; Mutant type; dryland
Online: 6 November 2020 (15:29:04 CET)
This study tested the association between FecXG point mutation located in exon 2 of BMP15 gene and the prolificacy of Dubasi, Shugor and Watish sheep ecotypes, under dryland farming, Sudan. Blood samples were randomly collected from unrelated 100 ewes (Dubasi; n= 30, Shugor: n= 30, and Watish: n= 40). Bone Morphogenetic protein (BMP15) gene was amplified using PCR-RFLP. Two genotypes were found in all studied breeds (heterozygous and wild type). The calculated total genotype frequencies of BB, Bb and bb genotypes were 0.31, 0.69 and 0.00, respectively, while allele frequencies were 0.66 for B and 0.34 for b. Litter size was influenced by the genotypes of BMP15 gene, parities and subtypes (p<0.05), highest for Watish and 4th parity. Alignment of BMP15 samples along with database reference sequence revealed that most sequence regions were identical except for one variable nucleotide at position 111 bp where a guanine (G) was replaced by adenine (A) in Watish and Shugor samples. All amino acids were the same at residue 275. Watish and Shugor breeds are more related. The study concluded that the presence of one copy of FecXG point mutation of BMP15 gene increased the litter size by 0.17 lambs in the studied ecotypes.
Subject: Biology, Animal Sciences & Zoology Keywords: Genome-wide association studies (GWAS); post-GWAS; sheep; tail fat deposition
Online: 11 June 2019 (10:04:39 CEST)
The type of tail of sheep is an important economic trait. However, the candidate genes associated with the tail type are uncertain. The objective of this study was to identify the genetic region and genotype responsible for the tail type phenotype. Here we perform a genome-wide association study (GWAS) in 40 large tailed Han sheep and 40 Altay sheep as case and 40 Tibetan sheep as control. The results indicated that a total 31 genome-wide significant SNPs associated with type of tail traits were detected. For significant SNPS loci, determine its physical location, and screening of candidate genes within section. By combining information of previously reported and annotated biological functional genes, we identified SPAG17, Tbx15, VRTN, NPC2, BMP2 and PDGFD as the most promising candidate genes for type of tail traits. Based on the above identified candidate genes on type of tail traits, we selected BMP2 and PDGFD to conduct the genetic effect analysis in a large Altay sheep and Tibetan sheep population. Rs119 T>C in the exon1 of BMP2 gene and 1 SNPs in the exon4 (rs69 C>A) of PDGFD gene were detected, rs119 that located on exon1 of BMP2 gene was TT genotype in Altay sheep, while with CC genotype in Tibetan sheep. On rs69 of PDGFD gene, Altay sheep with CC genotype, however, Tibetan sheep with AA genotype. These results indicated that the significant associations of SNPs detected in GWAS were indirectly caused by the genetic effects of BMP2 and PDGFD on sheep tail fat deposition.
ARTICLE | doi:10.20944/preprints202212.0099.v1
Subject: Biology, Animal Sciences & Zoology Keywords: Genetic parameters, (Co)variance components, Mecheri sheep, Animal models, Maternal genetic influence, Inbreeding
Online: 6 December 2022 (10:03:11 CET)
Determining genetic and non-genetic sources of variation in a breed is vital for the formulation of strategies for its conservation and improvement. The present study was aimed at estimating the (co)variance components and genetic parameters of Mecheri sheep by fitting six different animal models in the restricted maximum likelihood method, with a preliminary investigation on the performance of animals for non-genetic sources of variation. A total of 2616 lambs were studied, and varying levels of significance were found for the effect of period, season, parity of dam and birth type on different body weight traits. Direct heritability estimates derived from the best animal model for body weight at birth, 3 months, 6 months, 9 months and 12 months were 0.21, 0.24, 0.10, 0.15 and 0.09, respectively, and maternal heritabilities of the corresponding traits were 0.12, 0.05, 0.04, 0.04 and 0.04, respectively. The genetic correlations between body weight traits were all positive and moderate to strong except for birth weight with the other body weight traits. The significance of non-genetic factors studied in this work demanded a correction to improve the accuracy of the direct selection of lambs for body weight traits. The estimated genetic parameters identified the weaning weight as a selection criterion for the improvement in body weight of Mecheri lambs at different ages. Inbred individuals accounted for approximately 13% of the total population in the Mecheri sheep population studied. There were 877 founders in the population, and the actual effective size of the population was 128.48. The population's mean generation interval was 3.26. The mean inbreeding values ranged from 0.005 to 0.010 across generations. The population's average relatedness ranged from 0.001 to 0.014 across generations. Individual inbreeding was found to be 0.45 per cent for the entire population and 3.4 per cent for the inbred population.
ARTICLE | doi:10.20944/preprints201702.0101.v1
Subject: Medicine & Pharmacology, Other Keywords: ghrelin; serotonin N-acetyltransferase; tryptophan 5-hydroxylase 1; melatonin; pineal gland; photoperiod; sheep
Online: 28 February 2017 (11:13:01 CET)
Several studies suggests that ghrelin (GHRL) has neurobiological effects that extend beyond control of food intake. Our previous results confirmed that GHRL modulates the secretory activity of the pineal gland (PG) through nocturnal melatonin (MEL) secretion in sheep, the seasonally reproductive animals. Here we investigated the effects of GHRL (10 ng/ml) on the expression of enzymes limiting synthesis of MEL, including tryptophan 5-hydroxylase 1 (TPH1), serotonin N-acetyltransferase (AA-NAT) and its phosphorylated form p31T-AA-NAT in sheep PG explants (n = 72) during the 4-hour incubation in a gas-liquid interface, at a short (SD) and long (LD) photoperiods. After each hour of incubation selected explants were frozen in liquid nitrogen and stored at -80°C for subsequent analysis (real-time PCR, western-blotting, ELISA). Results show that GHRL regulates nightly MEL secretion in a TPH1-independent manner. The factor modulating GHRL activity was photoperiod. During SD photoperiod GHRL significantly reduced the expression of p31T-AA-NAT, AA-NAT and inhibited MEL secretion from PG explants. Whereas, during LD photoperiod no effect of GHRL on MEL secretion and expression of examined enzymes was noted. Studies indicate that GHRL directly affects PG under in vitro conditions and causes MEL secretion in animals which exhibit seasonality in reproductive and metabolic processes.
Subject: Medicine & Pharmacology, Clinical Neurology Keywords: blood-brain barrier; copper/iron homeostasis; neurodegenerative (Alzheimers, Parkinsons, Prion) disease; North Ronaldsay sheep
Online: 27 May 2019 (12:27:10 CEST)
The neurodegenerative diseases (Alzheimers, Parkinsons, amyotrophic lateral sclerosis, Huntingdons) and the prion disorders, have in common a dysregulation of metalloprotein chemistry involving redox metals (Cu,Fe,Mn). The consequent oxidative stress gives rise to protein plaques and neuronal cell death. An equilibrium exists between the functional requirement of the brain for Cu and Fe and their destructive potential with the production of reactive oxygen species. The importance of the brain barrier is highlighted in regulating the import of these metals. Upregulation of key transporters occurs in foetal and neonatal life when brain metal requirement is high and is down-regulated in adult life when need is minimal. By contrast a neonatal mode of CTR1 upregulation persists in feral N.Ronaldsay sheep. This has led to the premise that metal regulation may return to the default setting in ageing with implications for neurodegenerative disease.
ARTICLE | doi:10.20944/preprints201811.0307.v1
Subject: Biology, Animal Sciences & Zoology Keywords: PUFA; oils; body condition score; sheep milk composition; supplementation; canola; flaxseed; safflower; rice bran
Online: 13 November 2018 (10:05:15 CET)
The Australian dairy sheep industry is small and mostly based on a natural grass grazing system which can limit productivity. The current study tested different plant oil-infused and rumen protected polyunsaturated fats and their interactions with sire breeds to improve lactation traits and body condition score (BCS) of ewes grazing low quality pastures. It was hypothesised that supplementing lactating ewe diets plant-derived polyunsaturated oils will improve milk production and composition without compromising BCS. Sixty ewes (n=10/treatment) in mid-lactation, balanced by sire breed, parity, milk yield, body condition score, and liveweight were supplemented with: 1) control: wheat-based pellets without oil inclusion; wheat-based pellets including 2) canola oil (CO); 3) rice bran oil (RBO); 4) flaxseed oil (FSO), 5); safflower oil (SFO) and 6) rumen protected fat containing eicosapentaenoic acid and docosahexaenoic acid (RPO). Except for the control group, all supplementary diets included the same level of 50 ml/kg DM of oil and all diets were isocaloric and isonitrogenous. Experimental animals were grazed in the same paddock with ad libitum access to pasture, hay and water during the 10-week study. RPO was the most effective diet that enhanced milk, fat and protein yields by approximately 30, 13, and 31% respectively (P<0.0001). Significant increase in milk production was also observed in CO, RBO, and SFO (P<0.0001). Breed significantly influenced animal performance with higher milk yield recorded for crossbred Awassi x East Friesian (AW x EF) (578 g/day) vs purebred Awassi (452 g/day) (P<0.0001). This study provides empirical evidence for the use of rumen-protected and plant-derived oil-infused pellets as supplements under low quality pasture grazing conditions, to improve production performance of purebred Awassi and crossbred AW x EF ewes.
REVIEW | doi:10.20944/preprints202210.0097.v1
Subject: Life Sciences, Biotechnology Keywords: cow milk; sheep milk; goat milk; proteomics methods; bioactive peptides; antimicrobial peptides; allergenic potential; adulterations
Online: 8 October 2022 (08:22:24 CEST)
Milk is newborn’s food and an emulsion full of all necessary components for neonatal growth. Its consumption is worldwide and is the base for all dairy products. Because of the latter, many new technologies are growing, among them proteomics; in order to give new insights in milk’s compounds and to maximize the beneficial potential for consumers’ health. In this review, we aimed to gather data of proteomics studies for the majority of dairy animals and elucidate the role of milk bioactive compounds. Furthermore, special reference was made to milk fat globule membrane (MFGM) peptides and the result of thermal treatment in milk proteins. Finally, the proteomic approach regarding adulterations was included in the review.
ARTICLE | doi:10.20944/preprints202012.0567.v1
Subject: Life Sciences, Biochemistry Keywords: Peripheral Nerve Injury; Peripheral Nerve Regeneration; Peroneal Common Nerve; Animal Model; Sheep Model; Nerve Anatomy; Neurological Exam; Nerve Stereology
Online: 22 December 2020 (16:07:28 CET)
Thousands of people worldwide suffer from injuries in the peripheral nerve and deal daily with the resulting physiological and functional deficits. Recent advances in this field are still insufficient to guarantee effective outcomes, and the development of new and effective therapeutic options requires the use of valid preclinical models that effectively replicate the characteristics and challenges associated with these injuries in humans. In this study, we established a sheep model for common peroneal nerve injuries that can be applied in preclinical research with the advantages associated with the use of large animal models. In an integrative way, this article includes a detailed description of the anatomy and functionality of the peripheral nerves of sheep’s hind limb, the surgical protocol for accessing the common peroneal nerve, the induction of different types of nerve damage and the application of possible therapeutic options. A neurological exam protocol directed to the common peroneal nerve was also established, allowing to identify the changes and deficits related with the nerve injury and to evaluate the functional progression over time. Finally, a preliminary stereological study was carried out to establish control values for the healthy peroneal common nerves of this model and to identify preliminary differences between therapeutic methods. The ultimate goal is to demonstrate that sheep is a valid model of peripheral nerve injury to be used in pre-clinical and translational works and to evaluate the efficacy and safety of nerve injury therapeutic options before its clinical application in human and veterinary patients.