Are there differences in the adaptive profile of hair sheep and their crosses with wool breeds?

This study aimed to evaluate and compare the physiological performance of different genetic groups of sheep, by physiological variables and serum hormone levels, in a hot weather environment. Thirty sheep from five genetic groups were used: Santa Inês (SI), ½ Dorper + ½ Santa Inês (DO), ½ Ilê de France + ½ Santa Inês (IF), ½ Suffolk + ½ Santa Inês (SK), and ½ Texel + ½ Santa Inês (TX). The readings and records of physiological parameters (respiratory rate (RR), rectal temperature (RT), auricular cavity temperature (ACT), and surface temperature (ST)) were carried out at 7:00 am, 1:00 pm, and 7:00 pm, in 12 non-consecutive days. The collections of blood samples for hormone analysis (triiodothyronine (T3), thyroxine (T4), and cortisol (CORT)) is in four consecutive days. The environmental conditions of the experimental period caused a thermal discomfort in the sheep, but not a state of thermal stress. The thermolysis mechanisms, sensitive (ST and ACT) and latent (RR) processes, were enough to maintain their homeostasis (RT). The results showed that crossbred breeds presented a higher metabolism and were more efficient at dissipating heat through thermolysis than the SI breed. The crossbred breeds were efficient at dissipating heat through the elevation of body surface temperature and respiratory rate, mainly SK and TX, i.e., crossbred breeds, despite the wool cover, used thermoregulatory mechanisms that promoted lower variation of RT. The analysis of variance showed significant effects (P < 0.05) to the time factor in the responses of T4 and T3, and to the breed factor in the responses of CORT, T4, and T3. We did not observe interaction between the factors to any of the hormonal variables. Therefore, we can state that the effect of time was independent of breed and vice versa. Thyroid hormones presented lower blood concentration in the mornings (4.03 ± 0.82, T4; 65.08 ± 10.6, T3), increasing their concentration in the afternoon (4.60 ± 1.03, T4; 70.16 ± 14.17, T3). The thyroid hormones presented a normal circadian rhythm, with the exception of SK. Air temperature (AT) showed greater correlation with physiological variables than enthalpy (H) did, in the experimental conditions. However, H showed correlation with T4 and T3. The adaptive profile of the genetic groups under study are different, but the IF genetic group showed better performance under environmental conditions.

Genetic and phenotypic relationships between ewe reproductive performance and wool and growth traits in Uruguayan Ultrafine Merino sheep.

This study reports genetic parameters for yearling and adult wool and growth traits, and ewe reproductive performance. Data were sourced from an Uruguayan Merino flock involved in a long-term selection program focused on reduced fiber diameter (FD), and increased clean fleece weight (CFW) and live weight (LW). Pedigree and performance data from approximately 5,700 mixed-sex yearling lambs and 2,000 mixed-age ewes born between 1999 and 2019 were analyzed. The number of records ranged from 1,267 to 5,738 for yearling traits, and from 1,931 to 7,079 for ewe productive and reproductive performance. Data on yearling and adult wool traits, LW and body condition score (BCS), yearling eye muscle area (Y_EMA), and fat thickness (Y_FAT), and several reproduction traits were analyzed. The genetic relationships between FD and reproduction traits were not different from zero. Moderate unfavorable genetic correlations were found between adult CFW and ewe lifetime reproduction traits (-0.34 ±â€…0.08 and -0.33 ±â€…0.09 for the total number of lambs weaned and total lamb LW at weaning, respectively). There were moderate to strong positive genetic correlations between yearling LW and all reproduction traits other than ewe-rearing ability (-0.08 ±â€…0.11) and pregnancy rate (0.18 ±â€…0.08). The genetic correlations between Y_EMA and reproduction traits were positive and ranged from 0.15 to 0.49. Moderate unfavorable genetic correlations were observed between yearling FD and Y_FAT and between adult FD and BCS at mating (0.31 ±â€…0.12 and 0.23 ±â€…0.07, respectively). The genetic correlations between adult fleece weight and ewe BCS at different stages of the cycle were negative, but generally not different from zero. This study shows that selection for reduced FD is unlikely to have any effect on reproduction traits. Selection for increased yearling LW and Y_EMA will improve ewe reproductive performance. On the other hand, selection for increased adult CFW will reduce ewe reproductive performance, whereas selection for reduced FD will negatively impact body fat levels. Although unfavorable genetic relationships between wool traits and both FAT and ewe reproductive performance existed, simultaneous improvements in the traits would occur using appropriately designed indexes.

Fiber diameter (FD), clean fleece weight (CFW), live weight (LW), and reproductive performance are important traits in Merino flocks. This study estimated the genetic parameters for a range of production traits and ewe reproductive performance. Data from approximately 5,700 mixed-sex yearling lambs and 2,000 mixed-age ewes born in a single Uruguayan Merino flock were analyzed. There were generally favorable (positive) genetic correlations between LW and reproduction traits. The genetic relationships between FD and reproduction traits were generally negligible. In addition, moderate unfavorable (negative) genetic correlations were found between adult CFW and ewe reproduction traits. This study indicates that selecting finer fleeces will yield little to no change in ewe reproduction traits, whereas heavier fleeces are related to reduced ewe reproductive performance. On the other hand, genetically heavier yearling ewes will display greater reproductive performance.

Genomic Regions Associated with Wool, Growth and Reproduction Traits in Uruguayan Merino Sheep.

The aim of this study was to identify genomic regions and genes associated with the fiber diameter (FD), clean fleece weight (CFW), live weight (LW), body condition score (BCS), pregnancy rate (PR) and lambing potential (LP) of Uruguayan Merino sheep. Phenotypic records of approximately 2000 mixed-age ewes were obtained from a Merino nucleus flock. Genome-wide association studies were performed utilizing single-step Bayesian analysis. For wool traits, a total of 35 genomic windows surpassed the significance threshold (PVE ≥ 0.25%). The proportion of the total additive genetic variance explained by those windows was 4.85 and 9.06% for FD and CFW, respectively. There were 42 windows significantly associated with LWM, which collectively explained 43.2% of the additive genetic variance. For BCS, 22 relevant windows accounted for more than 40% of the additive genetic variance, whereas for the reproduction traits, 53 genomic windows (24 and 29 for PR and LP, respectively) reached the suggestive threshold of 0.25% of the PVE. Within the top 10 windows for each trait, we identified several genes showing potential associations with the wool (e.g., IGF-1, TGFB2R, PRKCA), live weight (e.g., CAST, LAP3, MED28, HERC6), body condition score (e.g., CDH10, TMC2, SIRPA, CPXM1) or reproduction traits (e.g., ADCY1, LEPR, GHR, LPAR2) of the mixed-age ewes.

Influence of targeted selective anthelmintic treatment on the productive performance of wool and hair lambs naturally infected with gastrointestinal nematodes in Brazil.

Targeted selective treatment (TST) is an alternative method to reduce the use of anthelmintics and delay the development of resistant nematode populations. However, there is limited information on the actual effects of this type of treatment on livestock productivity. The objective of this study was to evaluate the production performance of Santa Ines (hair) and Ile de France (wool) lambs naturally infected with gastrointestinal nematodes (GIN) under TST based on packed cell volume (PCV) versus suppressive anthelmintic treatments. Thirty-eight lambs were divided into two treatment groups: Suppressive treatment, animals were drenched with monepantel every two weeks and TST, animals were treated with the same anthelmintic when they presented PCV ≤ 20%. Feces, blood, and weight were measured weekly to determine eggs per gram of feces, PCV, total plasma protein, and weight gain. After animals were slaughtered, carcasses were weighed to determine carcass yield. In the TST group, substantial productive losses of approximately 21.3% in the wool and 25.9% in the hair lambs were observed in body weight compared to their counterparts. Significant differences in hematological variables occurred over the experimental period, especially in the wool lambs under TST. Favorable environmental conditions enabled infective larvae to survive and thrive on pasture. Haemonchus contortus and intestinal nematodes were the most common parasites found in the Ile de France lambs and the Santa Ines lambs, respectively. Although TST prevented mortality, it did not prevent production losses. Both breeds showed a significant drop in production due to GIN parasitism.

Sisal wool skin disease in Merino sheep in the Argentine Patagonia region: Identification and molecular diagnosis of Corynebacterium bovis from skin lesions.

BACKGROUND: Sisal wool condition is a skin disease affecting Merino sheep in the Argentine Patagonia region. Corynebacterium spp. isolates have previously been isolated from skin swabs from lesions, while specific identification of the bacteria involved has not been reported. HYPOTHESIS/OBJECTIVES: The aim of this work was to characterize the bacterial agent isolated from sisal wool lesions and to develop a diagnostic method for field surveillance. MATERIALS AND METHODS: Molecular identification of a collection of 72 isolates obtained previously was performed using PCR and 16S rRNA and rpoB sequencing. A field survey was carried out on two farms in the Río Negro province of Argentine Patagonia. Swab samples from sheep with and without skin lesions were collected and analysed by PCR and culture. RESULTS: Isolates analysed were confirmed by sequencing as Corynebacterium bovis. Using a PCR test without culture step, all field samples from affected sheep were positive for C. bovis; samples from the healthy skin from the same animals or clinically healthy sheep all were negative. CONCLUSIONS AND CLINICAL RELEVANCE: Sisal wool skin disease was associated with C. bovis infection based on culture and PCR methods; the latter may be useful for helping to pursue a disease control strategy.

SNP- and haplotype-based single-step genomic predictions for body weight, wool, and reproductive traits in North American Rambouillet sheep.

Rambouillet sheep are commonly raised in extensive grazing systems in the US, mainly for wool and meat production. Genomic evaluations in US sheep breeds, including Rambouillet, are still incipient. Therefore, we aimed to evaluate the feasibility of performing genomic prediction of breeding values for various traits in Rambouillet sheep based on single nucleotide polymorphisms (SNP) or haplotypes (fitted as pseudo-SNP) under a single-step GBLUP approach. A total of 28,834 records for birth weight (BWT), 23,306 for postweaning weight (PWT), 5,832 for yearling weight (YWT), 9,880 for yearling fibre diameter (YFD), 11,872 for yearling greasy fleece weight (YGFW), and 15,984 for number of lambs born (NLB) were used in this study. Seven hundred forty-one individuals were genotyped using a moderate (50 K; n = 677) or high (600 K; n = 64) density SNP panel, in which 32 K SNP in common between the two SNP panels (after genotypic quality control) were used for further analyses. Single-step genomic predictions using SNP (H-BLUP) or haplotypes (HAP-BLUP) from blocks with different linkage disequilibrium (LD) thresholds (0.15, 0.35, 0.50, 0.65, and 0.80) were evaluated. We also considered different blending parameters when constructing the genomic relationship matrix used to predict the genomic-enhanced estimated breeding values (GEBV), with alpha equal to 0.95 or 0.50. The GEBV were compared to the estimated breeding values (EBV) obtained from traditional pedigree-based evaluations (A-BLUP). The mean theoretical accuracy ranged from 0.499 (A-BLUP for PWT) to 0.795 (HAP-BLUP using haplotypes from blocks with LD threshold of 0.35 and alpha equal to 0.95 for YFD). The prediction accuracies ranged from 0.143 (A-BLUP for PWT) to 0.330 (A-BLUP for YGFW) while the prediction bias ranged from -0.104 (H-BLUP for PWT) to 0.087 (HAP-BLUP using haplotypes from blocks with LD threshold of 0.15 and alpha equal to 0.95 for YGFW). The GEBV dispersion ranged from 0.428 (A-BLUP for PWT) to 1.035 (A-BLUP for YGFW). Similar results were observed for H-BLUP or HAP-BLUP, independently of the LD threshold to create the haplotypes, alpha value, or trait analysed. Using genomic information (fitting individual SNP or haplotypes) provided similar or higher prediction and theoretical accuracies and reduced the dispersion of the GEBV for body weight, wool, and reproductive traits in Rambouillet sheep. However, there were no clear improvements in the prediction bias when compared to pedigree-based predictions. The next step will be to enlarge the training populations for this breed to increase the benefits of genomic predictions.

Intensification of Red-G dye degradation used in the dyeing of alpaca wool by advanced oxidation processes assisted by hydrodynamic cavitation.

Red-G dye is one of the main dyes used in the textile industry to dye alpaca wool. Therefore, considering the large volume of processed wool in Perú, the development of efficient technologies for its removal is a present scientific issue. In this study, an integrated system based on hydrodynamic cavitation (HC) and photo-Fenton process was evaluated to remove the Red-G dye. Using a hybrid cavitation device (venturi + orifice plate), the effect of pH was evaluated, achieving 21 % of removal at pH 2 which was more than 80 % higher compared to pH 4 and 6. The effect of temperature was also evaluated in HC-system at pH 2, where percentage of dye degradation increased at lower temperatures (around 20 °C). Then, 50.7 % of dye was removed under optimized condition of HC-assisted Fenton process (FeSO4:H2O2 of 1:30), that value was improved strongly by UV-light incorporation in the HC-system, increasing to 99 % removal efficiency with respect to HC-assisted Fenton process and reducing the time to 15 min. Finally, the developed cavitation device in combination with photo-Fenton process removed efficiently the dye and thus could be considered an interesting option for application to real wastewater.

New Insight into the Genome-Wide Diversity and Admixture of Six Colombian Sheep Populations.

Creole sheep represent a strategic genetic resource for populations living in marginal areas under financial restrictions on the American continent. Six Colombian sheep breeds (two wool (BCL-Boyacá and NCL-Nariño, 12 and 14 samples) and four hair (OPCE-Ethiopian, 54 samples; OPCS-Sudan, 74 samples; OPCP-Pelibeuy, 59 samples; OPCW-Wayúu, 24 samples) were genotyped using the Illumina Ovine SNP50 BeadChip. Data was also included from international 44 breeds from International Sheep Genomics Consortium (ISGC) and from data published in previous a previous work on the Caribbean and African breeds. Although geographically separated, wool (NCL, BCL) and hair types (OPCE, OPCS, OPCW) presented little genetic differentiation (FST 0.05) at a global level but several groups of animals separated suggesting local clustering due to geographical isolation. The OPCP underwent a recent crossing with Mexican Pelibuey, explaining its differentiation. Findings in this work such as the proximity to West African Djallonké (WAD) and Barbados Black Belly (BBB), suggest different introductions of African type animals from the Caribbean region on a pre-existing genetic basis formed by animals deriving from the first importations coming from Europe in colonial times. As expected, Colombian wool breeds showed, in particular in Admixture software results, a greater genomic component in common with European breeds and in particular with Iberian ones (Churra). This study provides a basis for future research into the genetic diversity within and between the Colombian sheep breeds analysed, and scientific data for policy decisions on Farm Animal Genetic Resources (FAnGR).

Copaifera langsdorffii Desf. bark extract: optimisation of dyeing conditions to wool and colour fastness properties.

The ability to add value to waste materials from industrial operations has come to the attention of the wood processing industry, with reports, for example, of extracts from the bark tree conveying colour and UV protection to textile fibres. The objective of the present work was to expand our developments in this arena by using Copaifera langsdorffii Desf. bark extract as a natural dye for textile dyeing. A complete 2³-statistical experimental design and the central point was elaborated. The results showed that the optimal dyeing conditions were 98 °C, for 60 min, using undiluted bark extract. The dyed fabric was analysed by a spectrophotometer using the CIELAB system for evaluation of the colour strength. The results showed a K/S value of 5.78, and the dyed fabric had good colour fastness to rubbing and washing.

Phenotypic characteristics of male lambs of woolen sheep breeds and their relationship with liquidity and price offered at auctions in Uruguaiana - Rio Grande do Sul

This study aimed at analyzing and comparing the phenotypic characteristics of height, body length, and fleece wool fineness with the liquidity and final price sold in auctions in the city of Uruguaiana, RS, Brazil, for three consecutive years (2015 to 2017). A total of 412 one-year-old (two teeth) male sheep, of the Australian Merino (n = 50), Polwarth (n = 130), and Corriedale (n = 232) breeds were evaluated. Height and length of the animals were measured on the day of the auction with a measuring tape, and animals were grouped into small or tall and short or long categories, as defined in this study. Wool fineness was measured using an Optical-based Fibre Diameter Analyser (FDA 2000) device and classified according to official wool classification standards (the Bradford System). There was no statistical difference in the average selling price of different breeds. There was a correlation between the breed and liquidity, in which Corriedale lambs were sold more than the Polwarth lambs, as expected; however, there was no such correlation for Merino lambs. The tall Merino lambs were sold at a higher selling price (R$ 2,449.11) than the small ones (R$ 1,826.59). Polwarth lambs exhibited positive correlations among height, length, and liquidity. Long and tall Corriedale lambs had a higher selling price (R$ 1,963.40 and R$ 1,915.02) than the short (R$ 1,656.38) and small (R$ 1,698.20) ones, respectively. In the case of Corriedale lambs, there was a positive correlation between length and liquidity. Wool fineness did not influence the selling price and liquidity in the three studied breeds. Conclusively, buyers of the Polwarth and Corriedale lambs prefer tall and long animals, regardless of the fleece wool fineness; only the height (taller lambs) seems to be a relevant factor for choosing the Merino breeders.(AU)

The effect of androgen on wool follicles and keratin production in Hetian sheep / Efeito do androgênio na produção de folículos e queratina em ovinos Hetianos

Abstract To investigate the optimal androgen concentration for culturing Hetian sheep wool follicle and to detect effects of androgen concentration on wool follicle cell proliferation and apoptosis using immunofluorescence labeling and real-time quantitative fluorescence determinations of wool keratin-associated protein gene expression levels. Wool follicles were isolated by microdissection and wool follicles and skin pieces were cultured in various concentrations of dihydrotestosterone (DHT) in culture medium. Next, daily lengthwise growth measurements of wool follicles were obtained using a microscopic micrometer. Cultured Hetian wool follicles were stained using the SACPIC method to reveal wool follicle structure, while sheep skin slices were used to observe cell proliferation by immunostaining and cell apoptosis using the TUNEL method. At the molecular biological level, keratin-associated protein (Kap) gene expression was studied using wool follicles cultured for various numbers of days in vitro. Effects of androgen concentrations on Hetian wool follicle growth and development were experimentally studied. EdU proliferation assays revealed that androgen promoted cell proliferation within wool follicle dermal papillae. TUNEL apoptosis detection demonstrated that androgen treatment could delay cell apoptosis. Quantitative reverse transcription polymerase chain reaction (qPCR) results demonstrated that gene expression level patterns of Hetian mountain sheep super-high sulfur protein. Kap1.1, KIF1.2, Kap2.12 and Kap4.2 gene expression level of the mountainous experimental group was significantly higher than plains Hetian sheep. An androgen concentration of 100 nM can promote the growth of Hetian wool follicle cells in vitro, resulting in overexpression of some genes of the Kap family.

Resumo Investigar a concentração ideal de andrógenos em cultura de folículos pilosos de carneiro Hetiano e detectar os efeitos da concentração de andrógenos na proliferação e apoptose de células foliculares, por meio de imunofluorescência e de determinação quantitativa, em tempo real, da fluorescência dos níveis de expressão gênica de proteína associada à queratina. Folículos pilosos foram isolados por microdissecção, e folículos de lã e pedaços de pele foram cultivados em várias concentrações de di-hidrotestosterona (DHT) em meio de cultura. Em seguida, medições diárias de crescimento longitudinal dos folículos capilares foram obtidas usando um micrômetro microscópico. Folículos de lã cultivados de Hetianos foram corados pelo método SACPIC para revelar a estrutura do folículo piloso, enquanto fatias de pele de carneiro foram usadas para observar a proliferação celular por imunocoloração e apoptose celular por meio do método TUNEL. Em âmbito da biologia molecular, a expressão gênica da proteína associada à queratina (Kap) foi estudada usando folículos capilares cultivados por vários dias, in vitro. Os efeitos das concentrações de andrógenos no crescimento e desenvolvimento dos folículos de lã de Hetianos foram estudados experimentalmente. Ensaios de proliferação de EdU revelaram que o andrógeno promoveu a proliferação celular dentro das papilas dérmicas do folículo piloso. A detecção de apoptose por TUNEL demonstrou que o tratamento com andrógeno poderia atrasar a apoptose celular. Os resultados da reação em cadeia da polimerase transcrição reversa quantitativa (qPCR) demonstraram que os padrões de expressão gênica da proteína de enxofre Kap1.1, KIF1.2, Kap2.12 e Kap4.2 foram significativamente maiores no grupo de ovinos Hetianos de montanha. Uma concentração de androgênio de 100 nM pode promover o crescimento de células foliculares de lã de Hetianos in vitro, resultando na superexpressão de alguns genes da família Kap.

Two strongly linked blocks within the KIF16B gene significantly influence wool length and greasy yield in fine wool sheep (Ovis aries)

BACKGROUND A previous genome-wide association study (GWAS) identified the kinesin family member 16B (KIF16B) as a candidate gene related to sheep wool production. In this work, DNA pool sequencing and SNPscanTM high-throughput genotyping methods were used to detect single-nucleotide polymor phisms (SNPs) in the sheep KIF16B gene. The correlations between the SNPs and wool length and greasy wool yield were systematically assessed. RESULTS Forty-five SNPs were identified and 37 of them were genotyped, including 10 exon mutations, 26 intron mutations, and 1 promoter region mutation. Most of the SNPs were of medium genetic diversity and at Hardy-Weinberg equilibrium (HWE). Among them, 10 SNPs were associated with greasy wool yield and 28 SNPs impact the wool length. Five specific SNPs were found to exert significant effects on the wool length in all body parts analyzed in this study. Furthermore, linkage disequilibrium (LD) analysis was conducted among SNP loci and they were found to be significantly associated with economically important traits. Two strongly linked SNP blocks were identified within these SNPs and they might exert significant impacts on the greasy wool yield and wool length. CONCLUSIONS The identified SNPs exert significant effects on wool production and could be considered as potential DNA markers for selecting the individuals with superior phenotypes

The effect of androgen on wool follicles and keratin production in Hetian sheep.

To investigate the optimal androgen concentration for culturing Hetian sheep wool follicle and to detect effects of androgen concentration on wool follicle cell proliferation and apoptosis using immunofluorescence labeling and real-time quantitative fluorescence determinations of wool keratin-associated protein gene expression levels. Wool follicles were isolated by microdissection and wool follicles and skin pieces were cultured in various concentrations of dihydrotestosterone (DHT) in culture medium. Next, daily lengthwise growth measurements of wool follicles were obtained using a microscopic micrometer. Cultured Hetian wool follicles were stained using the SACPIC method to reveal wool follicle structure, while sheep skin slices were used to observe cell proliferation by immunostaining and cell apoptosis using the TUNEL method. At the molecular biological level, keratin-associated protein (Kap) gene expression was studied using wool follicles cultured for various numbers of days in vitro. Effects of androgen concentrations on Hetian wool follicle growth and development were experimentally studied. EdU proliferation assays revealed that androgen promoted cell proliferation within wool follicle dermal papillae. TUNEL apoptosis detection demonstrated that androgen treatment could delay cell apoptosis. Quantitative reverse transcription polymerase chain reaction (qPCR) results demonstrated that gene expression level patterns of Hetian mountain sheep super-high sulfur protein. Kap1.1, KIF1.2, Kap2.12 and Kap4.2 gene expression level of the mountainous experimental group was significantly higher than plains Hetian sheep. An androgen concentration of 100 nM can promote the growth of Hetian wool follicle cells in vitro, resulting in overexpression of some genes of the Kap family.

'Meta-analysis of dry matter intake and neutral detergent fiber intake of hair sheep raised in tropical areas'.

Inadequate estimates of fiber and dry matter intake of sheep raised in tropical conditions may explain part of the inefficiency of those production systems. Therefore, we aimed to estimate dry matter intake (DMI) and neutral detergent fiber intake (NDFI) of hair sheep raised under tropical conditions. A meta-analysis of 61 independent performance experiments, comprising a total of 413 experimental units (treatment means or animals), was performed. Trials were conducted in tropical conditions, using hair sheep in growing and finishing phases and endowed with the following information: neutral detergent fiber (NDF) in diet, initial and final body weight (BW), average daily gain (ADG), DMI and NDFI of treatment means (51 studies) or individual data (10 studies). Data on organic matter and NDF digestibilities were collected to estimate D-value (Dv) and B-value (Bv) (20 and 33 studies, respectively). The equations obtained were: [Formula: see text] DMI (g/kg BW) as a function of Dv (g/kg DM) revealed a quadratic relationship, whose point of maximum DMI (38.69 g/kg BW) was obtained at 634.1 g/kg DM Dv. On the other hand, DMI decreased linearly as Bv (g/kg DM) increased. In conclusion, equations to predict DMI from BW and ADG as well to predict NDFI from dietary NDF were fitted with great accuracy and are recommended for hair sheep raised in tropical regions. DMI values were, in general, greater than those reported by the NRC, AFRC and INRA systems, which may be a reflection of the sheep breeds used in this study. Using Dv and Bv concepts was satisfactory to describe an integrated mechanism between metabolic and bulking regulation of DMI in sheep.

Suplementação gestacional na produção de lã de ovelhas e cordeiros / Gestacional supplementation in wool production of ewes and lambs

O objetivo deste estudo foi avaliar o efeito da suplementação durante diferentes períodos gestacionais sobre a produção de lã de ovelhas e cordeiros da raça Ideal. Foram utilizadas 53 ovelhas da raça Ideal, com escore corporal médio (3), inseminadas pela técnica de laparoscopia, com sêmen fresco de um único reprodutor; e seus cordeiros. Os tratamentos experimentais foram: sem suplementação (n=9); suplementação do início da gestação até 50 dias (n=11); suplementação dos 51 aos 100 dias de gestação (n=11); suplementação dos 101 aos 150 dias - final da gestação (n=11); e suplementação durante toda a gestação (n=11). A suplementação foi a 1,5% do peso corporal. Amostras de lã das ovelhas e dos cordeiros foram tomadas na região do costilhar esquerdo e enviadas ao laboratório para análises objetivas de finura de lã. As suplementações no terço final e durante toda a gestação proporcionavam os melhores resultados, com aumento de produção de lã e de peso das ovelhas. Ovelhas que receberam suplementação durante toda a gestação apresentaram maior diâmetro de fibra e peso corporal. O desempenho de lã dos cordeiros não foi influenciado pela alimentação de ovelhas durante a gestação.(AU)

The objective of this study was to evaluate the effect of supplementation during different gestational periods on the wool production of sheep and lambs of the Ideal breed. Fifty-three adult Ideal sheep were used, with a mean body score inseminated by the laparoscopy technique using fresh sperm from a single breeder and his lambs. Treatment groups: No supplementation (n=9); Supplementation in the beginning of gestation up to 50 days (n=11); Supplementation from 51 to 100 days of gestation (n=11); Supplementation from 101 to 150 days - end of gestation (n=11) ;and Supplementation throughout the gestation (n=11). The supplementation was at 1.5% of body weight. After birth, lambs were kept with their mothers in cultivated pasture of black oats and ryegrass. Wool samples from sheep and lambs were taken in the left-hand region and sent to the laboratory for objective analyzes of wool fineness. The supplementation performed in the final third and throughout the gestation provides the best results, with increased sheep weight. Ewes that received supplementation throughout pregnancy had greater fiber diameter and body weight. The wool performance of lambs was not influenced by feeding sheep during gestation.(AU)

Suplementação gestacional na produção de lã de ovelhas e cordeiros / Gestacional supplementation in wool production of ewes and lambs

O objetivo deste estudo foi avaliar o efeito da suplementação durante diferentes períodos gestacionais sobre a produção de lã de ovelhas e cordeiros da raça Ideal. Foram utilizadas 53 ovelhas da raça Ideal, com escore corporal médio (3), inseminadas pela técnica de laparoscopia, com sêmen fresco de um único reprodutor; e seus cordeiros. Os tratamentos experimentais foram: sem suplementação (n=9); suplementação do início da gestação até 50 dias (n=11); suplementação dos 51 aos 100 dias de gestação (n=11); suplementação dos 101 aos 150 dias - final da gestação (n=11); e suplementação durante toda a gestação (n=11). A suplementação foi a 1,5% do peso corporal. Amostras de lã das ovelhas e dos cordeiros foram tomadas na região do costilhar esquerdo e enviadas ao laboratório para análises objetivas de finura de lã. As suplementações no terço final e durante toda a gestação proporcionavam os melhores resultados, com aumento de produção de lã e de peso das ovelhas. Ovelhas que receberam suplementação durante toda a gestação apresentaram maior diâmetro de fibra e peso corporal. O desempenho de lã dos cordeiros não foi influenciado pela alimentação de ovelhas durante a gestação.(AU)

The objective of this study was to evaluate the effect of supplementation during different gestational periods on the wool production of sheep and lambs of the Ideal breed. Fifty-three adult Ideal sheep were used, with a mean body score inseminated by the laparoscopy technique using fresh sperm from a single breeder and his lambs. Treatment groups: No supplementation (n=9); Supplementation in the beginning of gestation up to 50 days (n=11); Supplementation from 51 to 100 days of gestation (n=11); Supplementation from 101 to 150 days - end of gestation (n=11) ;and Supplementation throughout the gestation (n=11). The supplementation was at 1.5% of body weight. After birth, lambs were kept with their mothers in cultivated pasture of black oats and ryegrass. Wool samples from sheep and lambs were taken in the left-hand region and sent to the laboratory for objective analyzes of wool fineness. The supplementation performed in the final third and throughout the gestation provides the best results, with increased sheep weight. Ewes that received supplementation throughout pregnancy had greater fiber diameter and body weight. The wool performance of lambs was not influenced by feeding sheep during gestation.(AU)

Análise da estrutura populacional de ovinos deslanados do núcleo de conservação / Population structure analysis in sheep without wool in the conservation nucleus

Este estudo analisou a estrutura populacional de ovinos deslanados do núcleo de conservação do estado do Ceará, Brasil. Os parâmetros populacionais foram estimados com base nos dados genealógicos de indivíduos das raças Santa Inês (SI), Somalis (SO) e Morada Nova (MN), nascidos entre os anos de 2001 e 2014. Os parâmetros estimados foram: número de gerações completas equivalentes (GCE), intervalo entre gerações (IEG), número de fundadores (Nf), número efetivo de fundadores (fe), número efetivo de ancestrais (fa), coeficiente de endogamia (F) e índice de contribuição genética (ICG). O GCE médio foi de 1,82, 2,78 e 1,52 para SI, SO e MN, respectivamente. O IEG foi próximo entre as raças, 3,67 anos em média. O Nf para SI, SO e MN foi igual a 225, 194 e 153, respectivamente. As razões fe/fa foram distantes de 1 nas três populações, o que indica ocorrência de gargalo genético, principalmente para SO. Os coeficientes médios de endogamia foram de 1,81%, 0,78% e 0,78% para SI, SO e MN, respectivamente. O ICG foi de 3,32, 5,38 e 2,87 para SI, SO e MN, respectivamente. Os parâmetros populacionais estimados apontam que parte da genética original desses rebanhos foi perdida, principalmente na população da raça Somalis.(AU)

This study evaluated the population structure of sheep without wool from the conservation nucleus in Ceará State, Brazil. Population parameters were estimated on genealogical records of Santa Ines (SI), Somali (SO,) and Morada Nova (MN) breeds, that were born between 2001 and 2014. The following estimates were obtained: number of complete generation equivalents (GCE), generation intervals (IEG), number of founders (Nf), effective number of founders (fe), effective number of ancestors (fa), inbreeding coefficient (F), and genetic contribution index (ICG). Average GCE was 1.82, 2.78, and 1.52 for SI, SO, and MN respectively. Mean IEG was similar between breeds, 3.67 years. The Nf was 225, 194, and 153 for SI, SO, and MN respectively. The fe/fa ratios were different to 1, which is an indication of genetic bottleneck, mainly for SO. The average inbreeding coefficients were 1.81%, 0.78%, and 0.78% for SI, SO, and MN respectively. The ICG was 3.32, 5.38, and 2.87 for SI, SO, and MN respectively. Estimated population parameters indicate that part of the genetics of these breeds was lost, mainly in Somalis.(AU)

Análise da estrutura populacional de ovinos deslanados do núcleo de conservação / Population structure analysis in sheep without wool in the conservation nucleus

Este estudo analisou a estrutura populacional de ovinos deslanados do núcleo de conservação do estado do Ceará, Brasil. Os parâmetros populacionais foram estimados com base nos dados genealógicos de indivíduos das raças Santa Inês (SI), Somalis (SO) e Morada Nova (MN), nascidos entre os anos de 2001 e 2014. Os parâmetros estimados foram: número de gerações completas equivalentes (GCE), intervalo entre gerações (IEG), número de fundadores (Nf), número efetivo de fundadores (fe), número efetivo de ancestrais (fa), coeficiente de endogamia (F) e índice de contribuição genética (ICG). O GCE médio foi de 1,82, 2,78 e 1,52 para SI, SO e MN, respectivamente. O IEG foi próximo entre as raças, 3,67 anos em média. O Nf para SI, SO e MN foi igual a 225, 194 e 153, respectivamente. As razões fe/fa foram distantes de 1 nas três populações, o que indica ocorrência de gargalo genético, principalmente para SO. Os coeficientes médios de endogamia foram de 1,81%, 0,78% e 0,78% para SI, SO e MN, respectivamente. O ICG foi de 3,32, 5,38 e 2,87 para SI, SO e MN, respectivamente. Os parâmetros populacionais estimados apontam que parte da genética original desses rebanhos foi perdida, principalmente na população da raça Somalis.(AU)

This study evaluated the population structure of sheep without wool from the conservation nucleus in Ceará State, Brazil. Population parameters were estimated on genealogical records of Santa Ines (SI), Somali (SO,) and Morada Nova (MN) breeds, that were born between 2001 and 2014. The following estimates were obtained: number of complete generation equivalents (GCE), generation intervals (IEG), number of founders (Nf), effective number of founders (fe), effective number of ancestors (fa), inbreeding coefficient (F), and genetic contribution index (ICG). Average GCE was 1.82, 2.78, and 1.52 for SI, SO, and MN respectively. Mean IEG was similar between breeds, 3.67 years. The Nf was 225, 194, and 153 for SI, SO, and MN respectively. The fe/fa ratios were different to 1, which is an indication of genetic bottleneck, mainly for SO. The average inbreeding coefficients were 1.81%, 0.78%, and 0.78% for SI, SO, and MN respectively. The ICG was 3.32, 5.38, and 2.87 for SI, SO, and MN respectively. Estimated population parameters indicate that part of the genetics of these breeds was lost, mainly in Somalis.(AU)

Effect of early shearing during gestation on the productive and reproductive behavior of female sheep offspring in their first 18 months of age.

The research has shown the interesting contributions of shearing in mid-gestation on the performance of lambs from birth to weaning. Other studies have reported that shearing at early pregnancy influences the development of the placenta and lamb live weight at birth. However, there was a lack of information on the effect of early-prepartum shearing on the behavior of the offspring from weaning onward. This study evaluated the effect of shearing ewes at 50 days of gestation on the growth, reproductive behavior and response to a gastrointestinal parasite challenge in the female offspring from weaning to 18 months old. Fifty-seven Polwarth female lambs were used, 22 being singles and 35 twins born to ewes either shorn at 50 days of pregnancy (PS, n = 23) or shorn at 62 days postpartum (U, control, n = 34) resulting in four subgroups: single lambs born to PS ewes (n = 8), born to U ewes (n = 14), twin lambs born to PS ewes (n = 15) or born to U ewes (n = 20). All progeny were managed together under improved pasture with a minimum forage allowance of 6% live weight on dry basis. Body weight, body condition score and fecal eggs count were recorded every 14 days from weaning to 18 months of age. Concentrations of progesterone were measured weekly (from 4 to 10 months of age and from 14 to 18 months of age) to establish the onset of puberty. Ovulation rate at an induced and a natural heat (545 ± 1.0 and 562 ± 1.0 day old) was recorded. Prepartum shearing did not affect the age at puberty or the ovulation rate of female offspring, but those born as singles were more precocious ( P = 0.03) and heavier ( P = 0.02) at puberty than twin born lambs. Both the average value of parasite egg count ( P = 0.0 7) and the Famacha index ( P = 0.02) for the entire study period were lower in lambs born to prepartum shorn ewes than those born to postpartum shorn ewes. In conclusion, shearing at 50 days of gestation did not affect the growth or the reproductive behavior of female offspring. However, female lambs born from ewe shorn during gestation showed a better response to the parasitic challenge, and further research is required to confirm this.

Comparative study of 13 candidate genes applying multi-reference normalization to detect the expression of different fineness in skin tissues of wool sheep.

Fiber diameter is a useful indicator of wool traits and it is the main determinant of wool quality and value. A comparative study was conducted to analyze the abundance and expression of 13 candidate genes using expression profile microarray analysis and to identify novel molecular markers associated with wool traits to provide a molecular basis for improving wool quality in sheep. Genes associated with fineness of skin tissue were identified using a real-time reverse transcriptase-polymerase chain reaction method with 18SrRNA, ß-Actin, and GAPDH used for multi-reference normalization. The results indicated that the expression levels of TXNIP, TFDP1, and FAIM genes in super-fine type wool sheep were higher than those in fine-type wool sheep; the corresponding expression ratios of super-fine to fine wool sheep were 1.45, 1.57, and 2.55, respectively. The expression levels of PIK3CA, ADAM9, and FZD3 genes were lower in super-fine wool sheep compared with fine-type wool sheep; the corresponding expression ratios were 0.61, 0.65, and 0.52, respectively. The other genes tested (RPS6KA, ABCG2, GSTA1, PTPN13, GJB3, PPARD, and LAMB1) were similarly expressed in both types of wool sheep. These results infer that lower expression of PIK3CA, ADAM9, and FZD3 genes was associated with lower fiber diameter, whereas lower expression of TXNIP, TFDP1, and FAIM genes was associated with higher fiber diameter.