Wool Growth Research Articles

MicroRNA expression profiles reveal wool development and fineness regulation in Gansu alpine fine-wool sheep

The development of wool has a complex regulatory mechanism both influenced by genetic and environmental factors. MicroRNAs (miRNA) were involved in various biological processes of animals, and may play an important role in the regulation of wool development. In this study, we comprehensively analyzed and identified the histological parameters of hair follicles, as well as the miRNAs, target genes, pathways, and Gene Ontology terms related to wool fineness regulation and wool growth and development using HE staining and RNA-Seqs methods. Both coarse (group C, mean fiber diameter (MFD) = 22.26 ± 0.69 μm, n = 6) and fine (group F, MFD = 16.91 ± 0.29 μm, n = 6) of Gansu alpine fine-wool sheep with different wool fineness were used in this study. The results showed that the primary follicle diameter and secondary wool fiber diameter in group C were significantly higher than those in group F (P < 0.05). And the number of primary and secondary hair follicles in group C was significantly lower than that in group F (P < 0.05). Furthermore, a total of 67 DE miRNAs and 290 potential DE miRNAs target genes were screened in the skin tissues of sheep from groups F and C, and some potential target genes related to wool fineness regulation were screened, such as CDH2, KRT82, FOXN1, LOC101106296, KRT20, MCOLN3, KRT71, and TERT. These genes were closely related to Glutathione metabolism, epidermal cell differentiation, keratinization, and regulation of hair cycle. Moreover, the regulatory network of miRNAs-mRNAs suggested that miRNAs (miR-129-x, novel m0079-3p, miR-2484-z, novel m0025-5P, etc.) may play a key role in the wool development and wool fineness regulation of Gansu alpine fine-wool sheep. In summary, this study expands the existing miRNAs database and provides new information for studying the regulation of wool development in Gansu alpine fine wool sheep.

Genetic diversity of United States Rambouillet, Katahdin and Dorper sheep

BackgroundManaging genetic diversity is critically important for maintaining species fitness. Excessive homozygosity caused by the loss of genetic diversity can have detrimental effects on the reproduction and production performance of a breed. Analysis of genetic diversity can facilitate the identification of signatures of selection which may contribute to the specific characteristics regarding the health, production and physical appearance of a breed or population. In this study, breeds with well-characterized traits such as fine wool production (Rambouillet, N = 745), parasite resistance (Katahdin, N = 581) and environmental hardiness (Dorper, N = 265) were evaluated for inbreeding, effective population size (Ne), runs of homozygosity (ROH) and Wright’s fixation index (FST) outlier approach to identify differential signatures of selection at 36,113 autosomal single nucleotide polymorphisms (SNPs).ResultsKatahdin sheep had the largest current Ne at the most recent generation estimated with both the GONe and NeEstimator software. The most highly conserved ROH Island was identified in Rambouillet with a signature of selection on chromosome 6 containing 202 SNPs called in an ROH in 50 to 94% of the individuals. This region contained the DCAF16, LCORL and NCAPG genes that have been previously reported to be under selection and have biological roles related to milk production and growth traits. The outlier regions identified through the FST comparisons of Katahdin with Rambouillet and Dorper contained genes with known roles in milk production and mastitis resistance or susceptibility, and the FST comparisons of Rambouillet with Katahdin and Dorper identified genes related to wool growth, suggesting these traits have been under natural or artificial selection pressure in these populations. Genes involved in the cytokine-cytokine receptor interaction pathways were identified in all FST breed comparisons, which indicates the presence of allelic diversity between these breeds in genomic regions controlling cytokine signaling mechanisms.ConclusionsIn this paper, we describe signatures of selection within diverse and economically important U.S. sheep breeds. The genes contained within these signatures are proposed for further study to understand their relevance to biological traits and improve understanding of breed diversity.

Increasing GSH-Px Activity and Activating Wnt Pathway Promote Fine Wool Growth in FGF5-Edited Sheep.

Fibroblast growth factor 5 (FGF5) plays key roles in promoting the transition from the anagen to catagen during the hair follicle cycle. The sheep serves as an excellent model for studying hair growth and is frequently utilized in various research processes related to human skin diseases. We used the CRISPR/Cas9 system to generate four FGF5-edited Dorper sheep and only low levels of FGF5 were detected in the edited sheep. The density of fine wool in GE sheep was markedly increased, and the proportion of fine wool with a diameter of 14.4-20.0 μm was significantly higher. The proliferation signal in the skin of gene-edited (GE) sheep was stronger than in wild-type (WT) sheep. FGF5 editing decreased cortisol concentration in the skin, further activated the activity of antioxidant enzymes such as Glutathione peroxidase (GSH-Px), and regulated the expression of Wnt signaling pathways containing Wnt agonists (Rspondins, Rspos) and antagonists (Notum) in hair regeneration. We suggest that FGF5 not only mediates the activation of antioxidant pathways by cortisol, which constitutes a highly coordinated microenvironment in hair follicle cells, but also influences key signals of the Wnt pathway to regulate secondary hair follicle (SHF) development. Overall, our findings here demonstrate that FGF5 plays a significant role in regulating SHF growth in sheep and potentially serves as a molecular marker of fine wool growth in sheep breeding.

Ovine KRT81 Variants and Their Influence on Selected Wool Traits of Commercial Value.

Keratins are the main structural protein components of wool fibres, and variation in them and their genes (KRTs) is thought to influence wool structure and characteristics. The PCR-single strand conformation polymorphism technique has been used previously to investigate genetic variation in selected coding and intron regions of the type II sheep keratin gene KRT81, but no variation was identified. In this study, we used the same technique to explore the 5' untranslated region of KRT81 and detected three sequence variants (A, B and C) that contain four single nucleotide polymorphisms. Among the 389 Merino × Southdown cross sheep investigated, variant B was linked to a reduction in clean fleece weight, while C was associated with an increase in both greasy fleece weight and clean fleece weight. No discernible effects on staple length or mean-fibre-diameter-related traits were observed. These findings suggest that variation in ovine KRT81 might influence wool growth by changing the density of wool follicles in the skin, the density of individual fibres, or the area of the skin producing fibre, as opposed to changing the rate of extrusion of fibres or their diameter.

An Analysis of the Wool Characteristics That Determine the Wool Price for White Wool in South Africa

This study evaluates the effects of white wool's characteristics (fibre diameter/fineness, staple strength, vegetable matter, and staple length) that contribute to determining the wool price in South Africa. The analysis was based on wool price data for the 2009 to 2019 production seasons. A multiple regression analysis of the price (R/kg) of White wool was applied to four independent variables: fibre diameter/fineness, staple strength, vegetable matter and staple length. Fibre diameter, staple length and clean yield, except vegetable matter, made a significant contribution (p &lt; 0.05) to the determination of wool price after all other independent variables were controlled. A one-unit increase in staple length was associated with a 0.018-unit increase in wool price (R/kg). One unit (micron) increase in fibre diameter/fineness resulted in a 0.331 unit decrease in wool price (R/kg). One unit (percentage) increase in clean yield resulted in a 0.115 unit increase in wool price (R/kg). The analysis found that a 1% increase in clean yield, a measure of the amount of clean, usable wool produced by a sheep, was associated with an average increase of 0.115 R/kg in the price of wool. This means that as clean yield increases, wool price tends to increase. Clean yield varies within sheep flocks due to varying amounts of wax and contaminants such as vegetable matter dirt, breed of sheep, and the environmental conditions during wool growth. There was no statistically significant association between vegetable matter and wool price. Wool farmers need to produce wool with low fibre diameter, good length of wool and high clean yield percentage for White wool. Additionally, farmers should focus on improving their production and marketing practices, and policymakers should consider implementing policies that support the wool industry and increase its competitiveness.

Integration Analysis of Hair Follicle Transcriptome and Proteome Reveals the Mechanisms Regulating Wool Fiber Diameter in Angora Rabbits.

Fiber diameter is an important characteristic that determines the quality and economic value of rabbit wool. This study aimed to investigate the genetic determinants of wool fiber diameter through an integration analysis using transcriptomic and proteomic datasets from hair follicles of coarse and fine wool from Angora rabbits. Using a 4D label-free technique, we identified 423 differentially expressed proteins (DEPs) in hair follicles of coarse and fine wool in Angora rabbits. Eighteen DEPs were examined using parallel reaction monitoring, which verified the reliability of our proteomic data. Functional enrichment analysis revealed that a set of biological processes and signaling pathways related to wool growth and hair diameter were strongly enriched by DEPs with fold changes greater than two, such as keratinocyte differentiation, skin development, epidermal and epithelial cell differentiation, epidermis and epithelium development, keratinization, and estrogen signaling pathway. Association analysis and protein-protein interaction network analysis further showed that the keratin (KRT) family members, including KRT77, KRT82, KRT72, KRT32, and KRT10, as well as CASP14 and CDSN, might be key factors contributing to differences in fiber diameter. Our results identified DEPs in hair follicles of coarse and fine wool and promoted understanding of the molecular mechanisms underlying wool fiber diameter variation among Angora rabbits.

Manipulation of neonatal ruminal populations at birth results in sustained effects on microbial populations and measures of health and production in merino and suffolk lambs

The efficiency of the microbial-driven fermentation process in the rumen is closely related to the efficiency of the ruminant host. This experiment examined the effect of manipulating the neonatal microbiota on postnatal development, immune function and productivity (liveweight gain and wool growth parameters). The trial examined the differences between naturally inoculated lambs (maternal control, n = 21) and those given ruminal fluid, which had been collected from ruminally-cannulated ewes, fed either a roughage diet (roughage, n = 14), or a grain-based diet (high grain, n = 14). At lambing, newborn lambs were tagged and weighed. Inoculation lambs received 10 ml of rumen fluid per inoculation, daily, for a total of 7 inoculations. Live weight, body condition scores, wool growth (greasy and clean wool weights), wool length, mean fibre diameter, and differential blood cell counts, and IgG and IgA in both blood and saliva) were quantified from birth until week 18 (slaughter). Total feed intake was recorded from weaning. Ruminal fluid was collected by stomach tube from 12 lambs from each treatment group and their dams (n = 7–8 per treatment, with the lower number of ewes coming about through ewes that had twins) at time of weaning (week 10). The pH of the ruminal fluid, the density of ciliated protozoa in ruminal fluid, and the composition of the ruminal bacterial populations were analysed. At slaughter (week 18), ileal samples were taken from the same focal lambs as were used for microbial analysis. The artificial inoculations resulted in significant differences in ruminal bacterial genera to those of naturally inoculated lambs at time of weaning (some 3 months post-lambing). Significant differences were also apparent in ileal bacterial communities at slaughter, between lambs which had received the inoculum from roughage-fed ewes and naturally inoculated lambs. Both the efficiency (growth, condition, feed conversion efficiency, carcass weight) and indices of health (mortalities, red blood cell count, blood haemoglobin concentration, haematocrit, and eosinophil counts) of the inoculated animals, were affected negatively by the inoculations ( < 0.05). There was a significant interaction between inoculum source and breed in terms of effects on all parameters measured. The effects of the high grain inoculation were significantly affected by breed, with high grain merinos found to have reduced mean fibre diameter (P < 0.05) and increased wool growth relative to the maternal control (P = 0.035). This effect was not noted in the suffolks. In summary, we have demonstrated that long-term effects on ruminal and intestinal microbiota can be generated by intervention in the normal process of ruminal inoculation in neonatal lambs. Moreover, there appeared to be genetic differences in response to artificial inoculation. Whilst the effects of artificial inoculation in this trial were negative in terms of indices of health and production, further studies of maternal diet and its effects on the natural establishment of the neonatal microbiota are warranted given the persistence of the effects and the interaction with breed.

A revised model of energy transactions and body composition in sheep.

A mechanistic, dynamic model was developed to calculate body composition in growing lambs by calculating heat production (HP) internally from energy transactions within the body. The model has a fat pool (f) and three protein pools: visceral (v), nonvisceral (m), and wool (w). Heat production is calculated as the sum of fasting heat production, heat of product formation (HrE), and heat associated with feeding (HAF). Fasting heat production is represented as a function of visceral and nonvisceral protein mass. Heat associated with feeding (HAF) is calculated as ((1 - km) x MEI), where km is partial efficiency of ME use for maintenance, and MEI = metabolizable energy intake) applies at all levels above and below maintenance. The value of km derived from data where lambs were fed above maintenance was 0.7. Protein change (dp/dt) is the sum of change in the m, v, and w pools, and change in fat is equal to net energy available for gain minus dp/dt. Heat associated with a change in body composition (HrE) is calculated from the change in protein and fat with estimated partial efficiencies of energy use of 0.4 and 0.7 for protein and fat, respectively. The model allows for individuals to gain protein while losing fat or vice versa. When evaluated with independent data, the model performed better than the current Australian feeding standards (Freer etal., 2007) for predicting protein gain in the empty body but did not perform as well as for gain of fat and fleece-free empty body weight. Models performed similarly for predicting clean wool growth. By explicit representation of the major energy using processes in the body, and through simplification of the way body composition is computed in growing animals, the model is more transparent than current feeding systems while achieving similar performance. An advantage of this approach is that the model has the potential for wider applicability across different growth trajectories and can explicitly account for the effects of systematic changes on energy transactions, such as the effects of selective breeding, growth manipulation, or environmental changes.

SOX18 Promotes the Proliferation of Dermal Papilla Cells via the Wnt/β-Catenin Signaling Pathway.

SRY-box transcription factor 18 (SOX18) is known to play a crucial role in the growth and development of hair follicles (HF) in both humans and mice. However, the specific effect of SOX18 on sheep hair follicles remains largely unknown. In our previous study, we observed that SOX18 was specifically expressed within dermal papilla cells (DPCs) in ovine hair follicles, leading us to investigate its potential role in the growth of hair follicles in sheep. In the present study, we aimed to examine the effect of SOX18 in DPCs and preliminarily study its regulatory mechanism through RNA-seq. We initially found that the overexpression of SOX18 promoted the proliferation of DPCs compared to the negative control group, while the interference of SOX18 had the opposite effect. To gain further insight into the regulatory mechanism of SOX18, we conducted RNA-seq analysis after knocking down SOX18 in Hu sheep DPCs. The result showed that the Wnt/β-Catenin signaling pathway was involved in the growth process of DPC after SOX18 knockdown. Subsequently, we investigated the effect of SOX18 on the Wnt/β-Catenin signaling pathway in DPCs using TOP/FOP-flash, qRT-PCR, and Western blot (WB) analysis. Our data demonstrated that SOX18 could activate the Wnt/β-Catenin signaling pathway in DPCs. Additionally, we observed that SOX18 could rescue the proliferation of DPCs after inhibiting the Wnt/β-Catenin signaling pathway. These findings underscore the essential role of SOX18 as a functional molecule governing the proliferation of DPCs. Additionally, these findings also greatly enhance our understanding of the role of SOX18 in the proliferation of DPCs and the growth of wool in Hu sheep.

Sulfur and Cystine Content in Various Sheep Wool Breeds and Their Correlation with Wool Growth and Strength

This scholarly article presents a comprehensive analysis of sulfur and cystine content in the wool of various sheep breeds, with a particular focus on their relationship with wool growth and strength. The breeds under scrutiny include the Askanian fine-wool, Prekos, Latvian dark-headed, Ukrainian Carpathian mountain, and Karakul breeds. Our research revolves around wool samples extracted from the scapula area before the spring shearing process. Our findings reveal that the highest sulfur content is observed in the wool of Karakul sheep (3.05 %) and Prekos sheep (2.90 %), whereas the lowest sulfur content is noted in Latvian dark-headed sheep (2.65 %). Conversely, the highest cystine content is exhibited in the wool of Askanian fine-wool sheep (11.87 %) and Prekos sheep (11.46 %), while the lowest cystine content characterizes the wool of Karakul sheep (8.99 %) and the Latvian dark-headed breed (10.10 %). The genetic factors, specifically breed-specific characteristics, impact on the rate of wool growth. The most rapid growth rates are observed in Karakul sheep (873 mg/cm/day) and Askanian fine-wool sheep (857 mg/cm/day). Slightly lower growth rates are noted in Prekos breed sheep (844 mg/cm/day) and Ukrainian Carpathian mountain breed sheep (766 mg/cm/day). The lowest growth rates are recorded in Latvian dark-headed sheep (742 mg/cm/day). Furthermore, we establish that the highest tensile strength values are associated with the coarse wool of Karakul sheep (9.6 cN/tex) and the semi-coarse wool of Ukrainian Carpathian mountain sheep (9.3 cN/tex), as these fibers possess the thickest cuticular layer. Conversely, the lowest tensile strength values are observed in the wool of Latvian dark-headed sheep (7.0 cN/tex) and Prekos breed (7.1 cN/tex). An examination of the data reveals that there is no statistically significant correlation between the content of sulfur and cystine and the rate of wool growth. However, a robust direct correlational relationship is identified between the sulfur content and fiber strength (with correlation coefficients of r = 0.831 for Karakul breed sheep wool, 0.713 for Latvian dark-headed, 0.698 for Ukrainian Carpathian mountain, 0.544 for Askanian fine-wool, and 0.460 for Prekos breed wool).

Effects of Sumac (Rhus coriaria) Seeds and Exogenous Fibrolytic Enzymes on Wool Growth of Awassi Male Lambs

Nutrition can have a significant effect on animal production. In recent years, many compounds have been widely used as feed additives to stimulate animals’ appetites and consequently improve animal productivity. Exogenous fibrinolytic enzymes are one of these feed additives, which have been used as a digestive stimulant in different types of animals. Sumac (Rhus coriaria) seeds and leaves have been widely used as an appetite stimulant. Therefore, this study aimed to determine the dietary effects of using 0.3% exogenous fibrolytic enzymes and 3% of grinds Rhus coriaria seeds on wool production and some physical traits of the Awassi lambs. Twenty-four male Awassi lambs with an average age of 4 months were randomly assigned to four dietary treatments, each containing six animals. The control group received a basal diet equivalent to 2% of body weight. The second group received the same diet supplemented with 3% sumac (Rhus coriaria) powder. The third group received the basal diet supplemented with 0.3% exogenous fibrolytic enzymes (protease, amylase, and cellulase). The fourth group received the basal diet supplemented with both 3% Rhus Coriaria powder and 0.3% exogenous fibrolytic enzymes. The experiment lasted 130 days in the animal house belonging to the College of Veterinary Medicine in Iraq. Some wool traits, including wool staple length, clean wool weight, greasy wool weight, wool fiber length, and wool fiber diameter, were measured. The results revealed significant differences in all measured wool quality traits among the treated groups compared to the control group. The group receiving the diet supplemented with a combination of exogenous fibrolytic enzymes and Rhus coriaria powder exhibited the most significant improvements in wool growth, overall wool production, and physical characteristics. These findings highlight the potential of using exogenous fibrolytic enzymes and sumac as effective appetite stimulants and enhancers of wool production in Awassi lambs.

Regulatory Effects of FGF9 on Dermal Papilla Cell Proliferation in Small-Tailed Han Sheep.

Fibroblast growth factor 9 (FGF9) is crucial for the growth and development of hair follicles (HFs); however, its role in sheep wool growth is unknown. Here, we clarified the role of FGF9 in HF growth in the small-tailed Han sheep by quantifying FGF9 expression in skin tissue sections collected at different periods. Moreover, we evaluated the effects of FGF9 protein supplementation on hair shaft growth in vitro and FGF9 knockdown on cultured dermal papilla cells (DPCs). The relationship between FGF9 and the Wnt/β-catenin signaling pathway was examined, and the underlying mechanisms of FGF9-mediated DPC proliferation were investigated. The results show that FGF9 expression varies throughout the HF cycle and participates in wool growth. The proliferation rate and cell cycle of FGF9-treated DPCs substantially increase compared to that of the control group, and the mRNA and protein expression of CTNNB1, a Wnt/β-catenin signaling pathway marker gene, is considerably lower than that in the control group. The opposite occurs in FGF9-knockdown DPCs. Moreover, other signaling pathways are enriched in the FGF9-treated group. In conclusion, FGF9 accelerates the proliferation and cell cycle of DPCs and may regulate HF growth and development through the Wnt/β-catenin signaling pathway.

Evaluation of growth, meat quality, and sensory characteristics of wool, hair, and composite lambs.

The objectives of this study were to evaluate the growth rates, carcass quality, shelf-life, tenderness, sensory characteristics, volatile compounds, and fatty acid composition of wool, hair, and composite (wool × hair) lambs. Twenty-one wether lambs [wool (Suffolk × Polypay/Targhee; n = 7), hair (Dorper × Dorper; n = 7), and composite (Dorper × Polypay/Targhee; n = 7)] were fed from weaning to finishing at the University of Idaho Sheep Center and subsequently harvested under United States Department of Agriculture inspection at the University of Idaho Meat Lab. At 48 h postmortem, carcass measurements were taken to determine the percent boneless closely trimmed retail cuts, yield grade, and quality grade. Loins were fabricated from each carcass and wet-aged at 0°C until 10-d postmortem. Following aging, 2.54-cm bone-in loin chops were cut and randomly assigned to 4 d of retail display, Warner-Bratzler Shear Force (WBSF), or sensory analyses. Thiobarbituric acid reactive substances were analyzed on days 0 and 4 of retail display while subjective and objective color measurements were observed once daily. Samples (24 g) were also collected for volatile compound and fatty acid analysis. A mixed model analysis of variance was used to assess breed differences. Discernable effects were considered at P < 0.05. Wool lambs had heavier hot carcass weights (P < 0.001), larger rib-eye area (P = 0.015), and higher dressing percent (P < 0.001) than the other breeds. There was an interaction observed between breed and days of retail display for browning (P = 0.006). On day 1 chops from the composite breed had more browning than chops from the wool breed. No differences were observed between groups for lean muscle L* values (P = 0.432), a* values (P = 0.757), and b* values (P = 0.615). Differences were not observed in lipid oxidation (P = 0.159), WBSF (P = 0.540), or consumer acceptability (P = 0.295). There were differences found for 7 of the 45 fatty acids detected and in 3 of the 67 volatile compounds detected. In conclusion, wool lambs were heavier and had a greater carcass yield than the hair lamb carcasses. Regardless of breed, consumers did not detect sensory traits that would impact their eating experience.

Sheep grazing

Context An accession of the annual legume Trigonella balansae Boiss. &amp; Reuter. has been selected for commercial release in Australia. Aims As part of a duty-of-care assessment, we tested the hypothesis that sheep grazing the trigonella accession will have liveweight, condition scores and wool production similar to those of sheep grazing two widely adopted annual legumes, subterranean clover (subclover, Trifolium subterraneum L. cv. Dalkeith) and French serradella (Ornithopus sativus Brot. cv. Erica). We also hypothesised that sheep grazing the three legumes will have similar meat quality and health, as indicated by blood plasma panel analysis. Methods Wethers (n = 6) grazed plots (n = 4) of three pasture species. Liveweight, condition scores and wool growth were measured, and a subset of animals were subject to blood sampling to assess health. Consumer sensory taste analysis was used to assess meat eating quality from two sheep per plot. Forage biomass, dry-matter digestibility, crude protein, fibre, mineral content and isoflavones were measured across the plant’s lifecycle. Key results There were no significant differences in liveweight, wool growth, wool yield or condition score that were associated with pasture species during the grazing period. There were differences in dry-matter digestibility, minerals and crude protein content of the pastures over time. As trigonella matured, it did not meet the minimum sulfur, phosphorus, manganese, molybdenum and copper requirements for mature sheep. We found some differences in indications of animal health; however, there were no significant systematic detrimental differences between sheep grazing trigonella and the other two species. In total, 2 of 24 individual sheep grazing trigonella had more than two plasma indicators of liver damage. There were no differences in meat tenderness, juiciness, flavour and overall consumer acceptability. Conclusions The data supported the hypotheses. Under the conditions of this experiment, the pasture legumes had the same relative feeding value. Some care must be taken in interpreting the outcome as the trigonellacomprised only 18% of the dry matter on offer at the termination of grazing. Implications Results of this study will be considered during the commercialisation process for T. balansae.

Shelter and shade for grazing sheep: implications for animal welfare and production and for landscape health

Shade and shelter may provide protection from cold and heat stress, a source of feed during prolonged or seasonal drought, specific essential nutrients, increased pasture and crop production and improved landscape health. Cold stress contributes to the average of 8% (single) and 24% (twin) of lambs that die within 3 days of birth in Australia and the estimated 0.7% of the Australian flock that die post-shearing during extreme or unseasonal weather. Shelter has resulted in an average reduction in mortality of 17.5% for twin-born lambs and 7% for single-born lambs according to Australian studies and decreases the susceptibility of ewes to metabolic disease and possibly dystocia. Because many of the published studies are from research areas where cold stress is expected, they are not indicative of industry-wide responses, a research priority is to determine the probability of lamb and ewe deaths from cold stress across different sheep production areas. Although shelter may improve lamb survival, ewes do not always choose to lamb in a sheltered location. For this reason, there is a requirement for research into the voluntary use of shelter in commercial-sized paddocks and the role that nutritive value of shelter plays in attracting and holding ewes to shelter, and to their lambs. Heat stress may also result in lamb deaths and influences feed conversion efficiency, appetite, reproduction, wool growth and disease susceptibility. The consequences of heat stress may go unnoticed over a yearly production cycle, although there is some evidence that shade may increase weaning rates and feed intake of grazing sheep. There are ancillary benefits from shade and shelter. Trees may improve crop production through reducing wind damage and evapotranspiration and provide timber. Shrubs provide feed during the summer–autumn feed gap or drought, are useful for the management of land degradation and provide habitat for native fauna. It is clear that shade and shelter in the correct locations provide a range of benefits to livestock and the landscape; nevertheless, adoption appears low. Research that focuses on defining the benefits on a farm or landscape scale is required to support extension programs.

Preliminary study of melatonin in the proliferation and apoptosis of Hu sheep dermal papilla cells in vitro

Previous studies have shown that melatonin has a certain regulatory effect on the growth of sheep wool. However, the mechanism of melatonin action remains unknown. In the present study, we aimed to understand the role of exogenous melatonin in the dermal papilla cells of Hu sheep. To confirm the optimal melatonin treatment regimen for Hu sheep dermal papilla cells, we detected the cell viability by exposing them to different concentrations of melatonin and different treatment times. The results showed that cell viability was best when dermal papilla cells were treated with 1000 pg/ml of melatonin for 48 h. According to the results of qPCR, CCK-8, EDU, Western blot, and Flow cytometry analysis, we found that 1000 pg/ml melatonin promoted the proliferation and inhibited the apoptosis of dermal papilla cells compared with the exogenous melatonin blank group (control group). Furthermore, we also found that 1000 pg/ml of melatonin promoted the cell cycle progress of dermal papilla cells according to the results of qPCR and Flow cytometry analysis. Overall, our findings showed that melatonin plays an important role in the dermal papilla cells of Hu sheep.

Effect of feeding wormwood herb (Artemisia absinthium Linn.) added total mixed ration on wool production and quality in sheep

ABSTRACT Emphasis over organic livestock production has resulted in increased interest in natural products. This study aims to evaluate dietary incorporation effect of wormwood (Artemisia absinthium) herb on wool characteristics and economics in sheep. In vitro assay was conducted to determine effective inclusion levels of feed additives followed by in vivo feeding trial for three months on crossbred (15) sheep distributed into three groups: control (Con) fed basal diet, groups fed diet added with 4.50% herb either alone (Hrb) and with 0.60% exogenous fibrolytic enzymes (EFE) (HrbEz), the levels chosen on basis of the best results of in vitro assay. Toward end of feeding trial, six days digestibility trial was conducted after which animals were shorn. Wormwood herb inclusions had significant (P < .05) positive effect on digestible nutrient contents and their intakes. Greasy and clean wool yields were higher (P < .05) resulted in lowering cost of wool production to the tune of 11.3% in Hrb and 22.2% in HrbEz group compared to control with no difference for all fiber quality characteristics except fiber length. It was concluded that incorporation of 4.50% wormwood herb with 0.60% of EFE in diet of sheep resulted in better wool growth economically with no adverse effect on quality.

Effects of exogenous melatonin on expressional differences of immune-related genes in cashmere goats.

The interplay between melatonin and immune system is well recognized in humans. The true integration of research on cashmere goat is still far from clear, especially for cashmere goat maintained in wool and cashmere growth. In this study, we applied various approaches to identify the complex regulated network between the immune-related genes and transcription factors (TFs) and to explore the relationship between melatonin and gene expression in cashmere goats. In total, 1,599 and 1756 immune-related genes were found in the blood and skin of cashmere goats, respectively, and 24 differentially expressed immune-related GO terms were highly expressed in blood after melatonin implantation. We studied the melatonin-dependent networks between the TFs and immune-related genes in cashmere goat. The 3 major regulatory networks were interconnected through TFs. The TFs, such as PHF5A, REXO4, STRAP, JUNB, GATAD2A, ZNF710, and VDR, were also expressed in the blood and skin tissue of cashmere goat. In addition, most genes in these networks, such as VDR, JUNB, and Trib3, were involved in WNT pathway, which is related to cashmere wool growth regulation. On the network basis, we developed a knockout mouse model to identify the network interaction. We observed that 8 high-sulfur protein genes, 12 keratin (KRT) genes, and 19 keratin associated protein (KRTAP) genes related to the growth of cashmere wool were almost not expressed in Trib3 -/- rat skin. Our results suggested that the expression of genes related to wool and cashmere growth may be regulated by the interaction network between genes affected by melatonin and immune-related genes. In summary, we outlined some particularly promising ways for future research on immune-related genes of cashmere goats and the role of melatonin in wool and cashmere growth.

Changes in Hormones and Some Antioxidant Markers That Correlated to Zinc Deficiency and Affecting Wool Growth in Male Lambs

Changes in Hormones and Some Antioxidant Markers That Correlated to Zinc Deficiency and Affecting Wool Growth in Male Lambs

Characterizing the vaginal microbiota of high and low producing Poll Merino and White Suffolk ewes.

There is a substantial, and growing, body of research focused on manipulating gastrointestinal microbes to affect health and production. However, the maternal vaginal microbiota and its effects on neonatal inoculation and lifetime production have received little attention. We aimed to characterize the vaginal microbes of domesticated sheep to determine whether they differ across sheep breeds with differing meat and wool growth potentials and to determine a link between vaginal microbes and high and low producing animals. A flock of White Suffolk (n = 136) and Poll Merino (n = 210) ewes were sorted by the Australian Sheep Breeding Values (ASBV), for yearling fleece weight in the Merino and by post-weaning weight in the Suffolk ewes. The top and bottom ASBV sheep were selected for sampling and the resulting treatment groups were; High Suffolk (n = 12), Low Suffolk (n = 12), High Merino (n = 12), and Low Merino (n = 12) ewes. A double guarded culture swab was used to sample from the surface of the vaginal epithelium. Diversity profiling analysis of vaginal bacterial communities was conducted using 16S rRNA amplicon sequencing. Breed and ASBV group differences in bacterial communities were tested. Within breed, there were no significant differences in ewe vaginal bacterial communities associated with ewe production parameters; however, there was a significant difference in ewe vaginal bacterial communities between breeds. We have been able to characterize the normal vaginal microbiota of nonpregnant ewes and demonstrate a rich microbial community.