Female Hair Research Articles

Dynamics of the total mercury content in the hair of adolescent residents of the industrial center of Northwest Russia (Cherepovets City).

Total mercury content dynamics were evaluated in the hair of adolescent residents of the industrial center of North West Russia. The content of total mercury varied from less than 0.002 to 0.83mg/kg. The content of total mercury in the hair of males was 1.5-2 times lower than that of females. The relationship between the body mass index of females and the content of total mercury in the hair (for the entire observation period rs = 0.28-0.48, at p < 0.05) was observed. Metal's concentration in the hair of the study participants was found to depend on of fish consumption frequency. Total mercury concentration values were found to increase of 70% of the participants, by 0.03mg/kg per year on average, over 3years of study. Indicators of the content of total mercury in the hair of females and males in the city of Cherepovets did not exceed the standard values established in Russia and in the world. At the same time, the recorded values of the annual increase in the content of total mercury in the hair allow us to predict the potentially hazardous levels of metal in the body of the study participants when they reach adulthood.

Effectiveness of platelet-rich plasma in treating female hair loss: A systematic review and meta-analysis of randomized controlled trials.

Hair loss profoundly affects women's physical appearance and psychological health. Platelet-rich plasma (PRP) therapy has gained attention as a potential treatment for female hair loss. This systematic review and meta-analysis aim to evaluate the efficacy and safety of PRP in treating different forms of female hair loss. A comprehensive search was conducted across PubMed, EMBASE, Scopus, Cochrane Library, Web of Science, and ClinicalTrials.gov from January 2000 to May 2024. The focus was on randomized controlled trials investigating PRP treatment for various types of hair loss in women. The research protocol is registered with International Prospective Register of Systematic Reviews (CRD42024556190). The quality of the studies was evaluated using the Cochrane risk of bias tool (RoB 2). A total of 21 studies comprising 628 participants were included in the analysis. PRP treatment was found to significantly enhance hair density and thickness. Additionally, there was a significant reduction in the number of hairs pulled in the PRP group. Adverse effects were generally mild and transient, with no notable difference in pain or discomfort between the PRP and control groups (risk ratio: 1.01; 95% CI: 0.87-1.18). PRP therapy effectively enhances hair density and thickness in women with hair loss, with a favorable safety profile. However, the effects of PRP on hair density and thickness vary with dosage, injection duration, and ethnicity, indicating the need for tailored treatment protocols.

Genetic Differences between Male and Female Pattern Hair Loss in a Korean Population.

Studies on androgenetic alopecia (AGA or patterned hair loss (PHL)) have suggested different underlying pathological mechanisms between males and females. While many genetic factors for male hair loss have been identified through genome-wide association studies (GWASs), the genetic determinants of female hair loss remain unclear. In this study, we analyzed approximately 1000 individuals (436 males and 568 females) to identify sex-specific genetic factors. We conducted three independent GWASs for the total, male-only, and female-only groups, identifying three novel loci (rs7814359, rs2163085, and rs4793158 of the TSNARE1, FZD1, and GJC1 genes, respectively). rs7814359 showed a significant genome-wide association with AGA in the combined sex group and a weak association in both the male-only and female-only groups. The single nucleotide polymorphism (SNP) rs2163085 showed a significant genome-wide association with AGA in the combined group and notable significance in females. The rs4793158 SNP showed a suggestive association with AGA in both the combined and female-only groups. TSNARE1, related to rs7814359, is involved in vesicle transport. FZD1 is a key regulator of the Wnt signaling pathway. GJC1 is a gap junction protein. The associations of FZD1 and GJC1 with female-specific AGA suggest that sex hormones, such as estrogen, may influence FPHL through these genes. These findings will contribute to our understanding of the sex-specific pathophysiology of AGA.

Ascertaining sensitive exposure biomarkers of various metal(loid)s to embryo implantation

Close relationships exist between metal(loid)s exposure and embryo implantation failure (EIF) from animal and epidemiological studies. However, there are still inconsistent results and lacking of sensitive metal(loid) exposure biomarkers associated with EIF risk. We aimed to ascertain sensitive metal(loid) biomarkers to EIF and provide potential biological explanations. Candidate metal(loid) biomarkers were measured in the female hair (FH), female serum (FS), and follicular fluid (FF) with various exposure time periods. An analytical framework was established by integrating epidemiological association results, comprehensive literature searching, and knowledge-based adverse outcome pathway (AOP) networks. The sensitive biomarkers of metal(loid)s along with potential biological pathways to EIF were identified in this framework. Among the concerned 272 candidates, 45 metal(loid)s biomarkers across six time periods and three biomatrix were initially identified by single-metal(loid) analyses. Two biomarkers with counterfactual results according to literature summary results were excluded, and a total of five biomarkers were further determined from 43 remained candidates in mixture models. Finally, four sensitive metal(loid) biomarkers were eventually assessed by overlapping AOP networks information, including Se and Co in FH, and Fe and Zn in FS. AOP networks also identified key GO pathways and proteins involved in regulation of oxygen species biosynthetic, cell proliferation, and inflammatory response. Partial dependence results revealed Fe in FS and Co in FH at their low levels might be potential sensitive exposure levels for EIF. Our study provided a typical framework to screen the crucial metal(loid) biomarkers and ascertain that Se and Co in FH, and Fe and Zn in FS played an important role in embryo implantation.

Morphometric and Phenotypic Characterization of Pote Goats in Soket Laok Village, Tragah District, Bangkalan Regency, Madura

The purpose of this study was to analyze the morphometric characteristics of Pote goats in Soket Laok Village, Madura Island. The material used was 200 Pote goats with an age range from over 1 year (PI0&gt;6) to more than 3.5 years (PI8). The sample included 90 goats aged over 1 year (PI0&gt;6), 36 goats aged between 1 and 1.5 years (PI2), 54 goats aged between 1.5 and 2.5 years (PI4), 16 goats aged between 2.5 and 3.5 years (PI6), and 4 goats aged over 3.5 years (PI8). The method used is a survey method which includes conducting surveys and interviews. Data were obtained using a purposive sampling technique. The results showed that morphometric measurements on the head and body of Pote goats had the highest average at PI 8, which means that along with the increasing age of Pote goats, it will affect the body size of goats. The results of the dominant phenotypic characteristics of Pote goats are the shape of a pitcher udder, the shape of long drooping ears, the shape of flat horns, rectangular pupils, convex facial profiles, there is rewos hair both in males and females and there is no beard, and phenotypic Pote goats with different ages do not have significant differences.

The impact of prolactin and vitamin D levels as a prognostic markers of female hair loss

A limited number of case reports seem to point the interaction between thinning hair and a vitamin D deficiency. This research looked at the relationship between prolactin levels and vitamin D levels in women with hair loss. The anterior pituitary gland secretes a polypeptide hormone called prolactin, which has a variety of biological effects, including the capacity to encourage growth and have a proliferative influence on human keratinocytes. Calcium homeostasis is affected by this hormone as a result of deficiency in vitamin D. This study was conducted on 75 patients during the period from November 2019 to March 2021. Serum prolactin and vitamin D levels were measured by chemiluminescence through an immunoassay (automated) and fluorescence Immunoassay (FIA) for vitamin D measurement. Serum prolactin levels were significantly elevated in pregnant women with hair loss compared with healthy controls. Vitamin D and serum prolactin levels had a remarkable positive correlation (r = 0.661, P 0.005). Prolactin and vit. D may play a part in hair loss in women.

Hair from sexually active bucks strongly activates olfactory sensory inputs but fails to trigger early first ovulation in prepubescent does

Early exposure of does to sexually active bucks triggers early puberty onset correlating with neuroendocrine changes. However, the sensory pathways that are stimulated by the male are still unknown. Here, we assessed whether responses to olfactory stimuli are modulated by social experience (exposure to males or not) and/or endocrine status (prepubescent or pubescent). We used a calcium imaging approach on goat sensory cells from the main olfactory epithelium (MOE) and the vomeronasal organ (VNO). For both cell types, we observed robust responses to active male hair in females under three physiological conditions: prepubescent females isolated from males (ISOL PrePub), pubescent females exposed to males (INT Pub) and isolated females (ISOL Pub). Response analysis showed overall greater proportion of responses to buck hair in ISOL PrePub. We hypothesized that females would be more responsive to active buck hair during the prepubertal period, with numerous responses perhaps originating from immature neurons. We also observed a greater proportion of mature olfactory neurons in the MOE and VNO of INT Pub females suggesting that male exposure can induce plastic changes on olfactory cell function and organization. To determine whether stimulation by male odor can advance puberty, we exposed prepubescent does to active buck hair (ODOR). In both ODOR and females isolated from males (ISOL) groups, puberty was reached one month after females exposed to intact bucks (INT), suggesting that olfactory stimulation is not sufficient to trigger puberty.

Effects of female hair braiding on selected facial Anthropometrics

Objective: Effects of heavy hair braiding on facial anthropometrics have raised concerns in recent times. These concerns arise from the potential impact on cultural practices and the implications for physical appearance and self-perception. This study aimed to investigate the effects of braiding on the soft anthropometrics in face and head among students in Alex Ekwueme Federal University Ndufu Alike, Ebonyi State, Nigeria. Materials and methods: A total of 503 healthy participants, aged 19 to 25 years, were randomly recruited from an institution. Measurements of total facial length and face width were taken. A structured questionnaire was used, that contain anatomical, theatrical, and socio-psychological questions to evaluate the effects of braiding on the face and head. Participants responded using a Likert scale. Results: Mesocephalic shape was the commonest classification of the skulls based on cephalic indices. Relationship between age and facial parameters of the study population showed significant positive correlation (r = 0.17, p&lt;0.05). Majority of respondents agreed that face type/facial structure determines the type of braid (n = 138) and braid can pull the forehead backward (n = 102). Conclusion: This study will contribute to understanding the influence of braiding on facial and head anthropometrics among Nigerian students. This information can inform discussions on cultural practices and their implications for physical appearance and self-perception.

Effects of female hair braiding on selected facial Anthropometrics

Objective: Effects of heavy hair braiding on facial anthropometrics have raised concerns in recent times. These concerns arise from the potential impact on cultural practices and the implications for physical appearance and self-perception. This study aimed to investigate the effects of braiding on the soft anthropometrics in face and head among students in Alex Ekwueme Federal University Ndufu Alike, Ebonyi State, Nigeria. Materials and methods: A total of 503 healthy participants, aged 19 to 25 years, were randomly recruited from an institution. Measurements of total facial length and face width were taken. A structured questionnaire was used, that contain anatomical, theatrical, and socio-psychological questions to evaluate the effects of braiding on the face and head. Participants responded using a Likert scale. Results: Mesocephalic shape was the commonest classification of the skulls based on cephalic indices. Relationship between age and facial parameters of the study population showed significant positive correlation (r = 0.17, p&lt;0.05). Majority of respondents agreed that face type/facial structure determines the type of braid (n = 138) and braid can pull the forehead backward (n = 102). Conclusion: This study will contribute to understanding the influence of braiding on facial and head anthropometrics among Nigerian students. This information can inform discussions on cultural practices and their implications for physical appearance and self-perception.

Exposure estimates of parabens from personal care products compared with biomonitoring data in human hair from Northeast China

Parabens (PBs), a class of endocrine-disrupting chemicals (EDCs), are extensively used as additives in personal care products (PCPs); however, distinguishing between endogenous and exogenous contamination from PCPs in hair remains a challenge. We conducted a comprehensive analysis of the levels, distribution patterns, impact factors, and sources of PBs in 119 human hair samples collected from Changchun, northeast China. The detection rates of methylparaben (MeP), propylparaben (PrP), and ethylparaben (EtP) in hair samples were found to be 100%. The concentration of PBs in hair followed the order of MeP (57.48 ng/g) > PrP (46.40 ng/g) > EtP (6.80 ng/g). The concentration of PrP in female hair was significantly higher (65.38 ng/g) than that observed in male hair (7.82 ng/g) (p < 0.05). The levels of excretion rates of MeP (ERMeP) and excretion rates of PrP (ERPrP) in the hair-dying samples (ERMeP: 17.89 ng/day; ERPrP: 14.15 ng/day) were found to be 2.52 and 2.40 times higher, respectively, compared to the non-hair-dying samples (ERMeP: 7.09 ng/day; ERPrP: 6.05 ng/day). However, the system exposure dosage (SED) results revealed that although hair dyes exhibited higher PBs, human exposure was found to be lower than certain PCPs. The results of the correlation analysis revealed that toner, face cream, body lotion, and hair conditioner were identified as the primary sources of PBs in male hair. Furthermore, the human exposure resulting from the utilization of female hair dye and serum exhibited a positive correlation with hair ERMeP and ERPrP levels, indicating in the screening of samples, excluding hair samples using hair dye and haircare essential oil can effectively avoid the interference caused by exogenous contamination from PCPs.

Evaluation of brain injury in goats naturally infected with Coenurus cerebralis; brain specific biomarkers, acute inflammation, and DNA oxidation

This investigate goals are to establish the utility of brain-specific biomarkers (GFAP and S100B) in vivo and to assess the brain damage in C. cerebralis-infected goats using histopathological and immunopathological methods. The animal material of the study consisted of 10 healthy and 20 Coenurus cerebralis infected female hair goats. Serum GFAP and S100B concentrations were measured to determine brain damage. Serum S100B (p < 0.037), GFAP (p < 0.012), urea (p < 0.045), GGT (p < 0.001) and ALT (p < 0.001) concentrations in the C.cerebralis group were significantly higher than the control group. There was no significant difference between the C.cerebralis group and the control group for hsTnI (p > 0.078), creatinine (p > 0.099) and CK-MB (p > 0.725). In the histopathological examination, pressure atrophy and related inflammatory changes were observed due to mechanical damage of the parasite. Immunohistochemical examinations revealed that the parasite stimulated inflammation with the expression of TNF-α and caused DNA damage with the expression of 8-OHdG. As a result, when the data collected for this study are assessed as a whole, it is thought that the use of brainspecific GFAP and S100B biomarkers may be beneficial in determining brain damage in naturally infected hair goats with C.cerebralis. Changes in the levels of brain-specific biomarkers contribute significantly to determining the prognosis of the disease in vivo. Measurement of GFAP and S100B concentrations from serum offers an important alternative to the CSF method.

Human biomonitoring of heavy metals exposure in different age- and gender-groups based on fish consumption patterns in typical coastal cities of China

The study aimed to investigate heavy metals (HMs) concentrations in human hair based on fish consumption patterns in Qingdao, Xiamen, and Zhoushan. The (HMs) concentrations were determined using acid digestion and an inductively coupled plasma mass spectrometer (ICP-MS, NexION 300X, PerkinElmer). The associated health risks were investigated using risk assessment models described by the United States Environmental Protection Agency (USEPA). The order of fish HMs concentration in Qingdao was Cd<Pb<As>Cr<Cu<Zn, while The in Zhoushan and Xiamen the order was Cd<Pb<Cr<Cu<As<Zn. The highest concentrations of HMs in fish were found in Zhoushan and lowest in Xiamen. Zn showed the highest values in fish, while Cd and Pb were the lowest. The Cr concentration in Scomberomorus niphonius collected in Qingdao exceeded the safety standards. The HMs in both male and female hair followed a descending order of Zn>Cu>Pb>Cr>As>Cd in all three study areas. The hair Zn concentration in 28 % of the studied population exceeded the safety standards. Overall, the hair HMs concentration was found to be high in middle-aged groups (19–45 and 45–59), and the hair HMs concentrations were high, especially in the case of females. A significant correlation was noticed between hair As (0.119; p < 0.05), Cr (0.231; p < 0.05),) and Cu (0.117; p < 0.05),) and fish consumption frequency. High Odd ratios (>2) were noticed for As, Cu and Zn in high fish-eating frequency. A significant non-carcinogenic risk was noticed in human Cr exposure (1.10E+00) in Xiamen, and the hazard index values indicated non-carcinogenic risk in Xiamen and Zhoushan. The carcinogenic risk for human As exposure (2.50E-05–7.09E-03) indicated a significant cancer risk.

A Bio-Indicator Pilot Study Screening Selected Heavy Metals in Female Hair, Nails, and Serum from Lifestyle Cosmetic, Canned Food, and Manufactured Drink Choices.

Lifestyles, genetic predispositions, environmental factors, and geographical regions are considered key factors of heavy metals initiatives related to health issues. Heavy metals enter the body via the environment, daily lifestyle, foods, beverages, cosmetics, and other products. The accumulation of heavy metals in the human body leads to neurological issues, carcinogenesis, failure of multiple organs in the body, and a reduction in sensitivity to treatment. We screened for Cr, Al, Pb, and Cd in selected foods, beverages, and cosmetics products depending on questionnaire outcomes from female volunteers. We also screened for Cr, Al, Pb, and Cd on hair, nails, and serum samples using inductively coupled plasma mass spectrometry (ICP-MS) from the same volunteers, and we analyzed the serum cholinesterase and complete blood picture (CBC). We performed an AutoDock study on Cr, Al, Pb, and Cd as potential ligands. Our results indicate that the most elevated heavy metal in the cosmetic sample was Al. In addition, in the food and beverages samples, it was Pb and Al, respectively. The results of the questionnaire showed that 71 percent of the female volunteers used the studied cosmetics, food, and beverages, which were contaminated with Cr, Al, Pb, and Cd, reflecting the high concentration of Cr, Al, Cd, and Pb in the three different types of biological samples of sera, nails, and hair of the same females, with 29 percent of the female volunteers not using the products in the studied samples. Our results also show an elevated level of cholinesterase in the serum of group 1 that was greater than group 2, and this result was confirmed by AutoDock. Moreover, the negative variation in the CBC result was compared with the reference ranges. Future studies should concentrate on the actions of these heavy metal contaminations and their potential health consequences for various human organs individually.

Effect of oxidative stress on the reproductive performance of Hair Goat

Small ruminants are the type of animals that make the most of unsuitable land and contribute significantly to the country's economy. In order to achieve maximum yield from these animals, it is necessary to optimize nutrition and minimize stress factors. One of the important consequences of management and nutrition has been demonstrated by scientists to be oxidative stress. Oxidative stress affect the normal functioning of many physiological systems. In this study, oxidative stress index (OSI), total oxidation level (TOS) and total antioxidant (TAS) levels were investigated in 20 male and 100 female hair goats during the breeding season (October) and out-of-season (May). Females between the ages of 2-6 years and male hair goats aged 2-4 years were used in the study. The correlation between TAS, TOS, and OSI and fertility was evaluated according to sex and season. TAS, TOS and OSI values in female hair goats in October and May were, respectively; 1.28, 1.34; 11.02, 7.13; 0.87, 0.53; in males 1.32, 1.44; 4.24, 8.84; 0.32, 0.63 μmol/L. As a result, it was concluded that as the TOS level increased, the yield of the offspring decreased, and the increase in the TAS level positively affected the yield of the offspring.

The change of copper, zinc, iodine, and selenium contents in the scalp hair of healthy females and the efficacy of herbal extract shampoo treatment

We investigated shampoo-related changes in levels of some trace elements in the scalp hair of females and their impact on scalp skin properties. Sixty healthy women divided into control and experimental group who used regular shampoo and Urtica cannabina (U.cannabina) extract shampoo, respectively. Scalp skin was examined using an electronic skin analyzer, and trichometric analysis was performed with a Folliscope. The collected scalp hair samples were digested and measured using inductively coupled plasma-mass spectrometry (ICP-MS). The average copper (p=0.05), zinc (p=0.0002), and iodine (p=0.0004) levels increased notably, whereas the selenium content decreased slightly (p=0.337) in the experimental group. We found that the average iodine content in scalp hair of Mongolian females was three times lower than the global average. The average increase in trace elements may be considered to be due to the transfer of an element into the human scalp during shampooing. These results indicate that some trace elements in human scalp hair are not only associated with nutritional status and environmental factors, but cosmetic products can also affect the trace element composition. The hair growth, diameter, and density gradually increased and were higher in the experimental group than in the control group. Scalp skin moisture, sebum, and pH values increased in the experimental group, whereas the control group showed no notable difference. Herbal extracts may potentially support scalp hair growth and increase the hair density. This ability can be explained by the trace elements in the herbal extract, which may play a key role in inducing hair growth.

Socio-economic Impacts of Water Project on the Community Livelihood in Peri-urban of Tanzania: Case study Gairo District – Morogoro Region

This study analyzed the socio-economic impacts of water projects on community livelihood in peri-urban Tanzania. It employed a cross-sectional research design, and a survey questionnaire was distributed to 353 households that were randomly selected by probability sampling procedures. Data were analysed using the logistic regression model. This study was guided by theory of Peri-Urban Turbulence (PUT) which is founded on the idea of changes in the balance and magnitude of natural and caused infrastructure and local and distant established arrangements during the transition, primarily in fast-growing urban areas of the Global South. The findings suggests the respondents’ year of schooling positively affect household access to water. Having one additional year of schooling may increase the chance to access to water facilities. Furthermore, the average household head’s monthly income was a significant explanatory variable at a one percent level of significance. Besides, non-farm activities were significantly associated to access to water. Nevertheless, the study identified the four major economic activities that the community engaged in as a result of water accessibility; male and female hair saloon salons, petty trading in village open auctions, vegetable gardening, and motorbike riding. Among of the four major economic activities performed, petty trading in the village open auction business is the most practiced. One can conclude that, the existence of water projects promotes socio- and economic development.

Hematological Parameters in Hair Goats During and out of Breeding Season Hair Goats Seasonal Hematological Parameters

Background: The hair goat of Anatolia is a breed that has adapted to rugged and mountainous areas and is known to be very resistant to diseases. As the world faces the problem of climate change, we believe that knowing the hematological characteristics of hair goats will provide great benefits for goat breeding. Objectives: This study was performed to determine possible differences in the blood parameters of adult (male and female) hair goats during and out of the breeding season. Methods: For this purpose, blood samples were taken from clinically healthy adult male and female hair goats (n=36, 3-4 years old) in the spring and autumn seasons. Regarding the whole blood, white blood cell (WBC), red blood cell (RBC), hemoglobin (Hb), hematocrit (Hct), mean red blood cell volume (MCV), mean red blood cell hemoglobin (MCH), average red blood cell hemoglobin concentration (MCHC) and red blood cell distribution width (RDW) values were determined. Results: In the study, MCV values in males were not significantly (P≥0.05) different between spring and autumn, while all other parameters showed significant differences (P≤0.05). In females, WBC, RBC, Hb, Hct, and RDW blood values were higher in the autumn (estrus period) than in the spring (anestrus period), and the differences were found to be significant (P≤0.05). Comparing males and females between the estrus and anestrus seasons, WBC and MCHC were found to be significantly different (P≤0.05) between males and females in May. In contrast, the difference between other parameters was not significant. In October (estrus season), the MCV value was not significantly different between males and females; however, all other parameters were significantly different (P≤0.05). Conclusion: As a result, there were significant differences in hematological parameters of hair goats based on gender and the breeding season.

Spatial distribution, impact factors, and potential health implications of trace elements in human hair from capital residents in China

We analyzed the levels, spatial distribution, impact factors, source apportionment, and potential health implications of trace elements (V, Zn, Cu, Mn, Ni, Mo, and Co) in 1202 human hair samples of urban residents aged 4–55 from 29 cities in China. The median values of seven trace elements in hair were found in the following increasing order: Co (0.02 μg/g) < V (0.04 μg/g) < Mo (0.05 μg/g) < Ni (0.32 μg/g) < Mn (0.74 μg/g) < Cu (9.63 μg/g) < Zn (157 μg/g). The spatial distribution of these trace elements in the hair from the six geographical subdivisions varied depending on the exposure sources and impact factors. Principal component analysis (PCA) revealed that Cu, Zn, and Co in the hair samples of urban residents were primarily derived from food, whereas V, Ni, and Mn were attributed to industrial activities and food. Majority of the hair samples (up to 81%) from North China (NC) exceeded the recommended value for V content, whereas up to 59.2%, 51.3%, and 31.6% samples from Northeast China (NE) exceeded the recommended values for Co, Mn, and Ni contents, respectively. The levels of Mn, Co, Ni, Cu, and Zn were significantly higher in female hair than those in male hair, whereas the levels of Mo were higher in male than in female hair (p < 0.01). Furthermore, significantly higher Cu/Zn ratios were observed in the hair of male residents than those in the female residents (p < 0.001), indicating a higher health risk for male residents.

Macromineral requirements for maintenance and growth in male and female hair sheep

A better understanding of the nutritional requirements of sheep, especially in terms of minerals, is crucial for improving production. We estimated the net requirements for Ca, P, K, Mg, and Na for gain (NCag, NPg, NKg, NMgg, and NNag) and maintenance (NCam, NPm, NKm, NMgm, and NNam) in male and female hair sheep. Six datasets with 248 individual records of hair sheep (139 non-castrated males, 75 castrated males and 34 females) were used to estimate the net macromineral requirements for gain. To estimate the net macromineral requirements for maintenance, 52 observations (26 non-castrated and 26 castrated males) were used. A meta-analytical approach was applied, using non-linear mixed effects models and the study as a random effect. Based on information criteria for model selection, heterogeneous variance functions were more likely to describe mineral requirements with a low level of model selection uncertainty. The adopted criteria allowed the choice of the best models to represent the macromineral requirements. The chosen models explained the observed variability in the sex, and the choices were based on a low level of uncertainty (w ≥ 0.90). Irrespective of sex, NCag and NPg decreased with increasing BW from 10 to 30 kg and average daily gain (ADG) of 150 g/day, ranging from 1.71-1.38; 1.83-1.57; 1.82-1.51 of Ca and 0.86-0.66; 0.92-0.78; 0.92-0.75 of P for non-castrated males, castrated males, and females, respectively. The NKg remained constant, with mean values of 0.26 g/day. The NNag range was 0.17 to 0.14 g/day for non-castrated males, 0.20 to 0.25 g/day for females, and constant (0.18 g/day) for castrated males with an increase in BW from 10 to 30 kg and an ADG of 150 g/day. Macromineral requirements for maintenance (mg/kg BW) and retention (%) were 23.70 and 54.30 for Ca, 25.33 and 79.80 for P, 11.74 and 5.00 for K, 2.63 and 8.50 for Mg, and 7.01 and 8.10 for Na for males. The International Committees did not provide inferences about the sex influence on mineral requirements. Our study indicates that sex is one factor that influences the macromineral requirements for gain. The information generated in this study can be used to optimize the mineral management of hair sheep in the growing phase in tropical regions.

Effects of the Level and Composition of Concentrate Supplements before Breeding and in Early Gestation on Production of Different Hair Sheep Breeds.

Female hair sheep, 27 Dorper (DOR), 41 Katahdin (KAT), and 39 St. Croix (STC), were used to determine influences of the nutritional plane before breeding and in early gestation on feed intake, body weight, body condition score, body mass indexes, blood constituent concentrations, and reproductive performance. There were 35 multiparous and 72 primiparous sheep, with initial ages of 5.6 ± 0.25 years and 1.5 ± 0.01 years, respectively (average overall initial age of 2.8 ± 0.20 years). Wheat straw (4% crude protein; dry matter [DM] basis) was consumed ad libitum and supplemented with approximately 0.15% initial body weight (BW) of soybean meal (LS) or a 1:3 mixture of soybean meal and rolled corn at 1% BW (HS; DM). The supplementation period was 162 days, with the breeding of animals in two sets sequentially, with the pre-breeding period 84 and 97 days, and that after breeding began at 78 and 65 days, respectively. Wheat straw DM intake (1.75, 1.30, 1.57, 1.15, 1.80, and 1.38% BW; SEM = 0.112) was lower (p < 0.05), but average daily gain (-46, 42, -44, 70, -47, and 51 g for DOR-LS, DOR-HS, KAT-LS, KAT-HS, STC-LS, and STC-HS, respectively; SEM = 7.3) was greater (p < 0.05) for HS than LS treatment during the supplementation period. Additionally, changes in body condition score during the supplementation period (-0.61, 0.36, -0.53, 0.27, -0.39, and -0.18; SEM = 0.058), and changes in body mass index based on height at the withers and body length from the point of the shoulder to the pin bone (BW/[height × length], g/cm2) from 7 days before supplementation (day -7) to day 162 were -1.99, 0.07, -2.19, -0.55, -2.39, and 0.17 for DOR-LS, DOR-HS, KAT-LS, KAT-HS, STC-LS, and STC-HS, respectively; (SEM = 0.297) were affected by supplement treatment. All blood constituent concentrations and characteristics addressed varied with the day of sampling (-7, 14, 49, 73, and 162) as well as the interaction between the supplement treatment and the day (p < 0.05), with few effects of interactions involving breed. Birth rate (66.7, 93.5, 84.6, 95.5, 82.8, and 100.0; SEM = 9.83) and individual lamb birth weight (4.50, 4.61, 4.28, 3.98, 3.73, and 3.88 kg; SEM = 0.201) were not affected by supplement treatment (p = 0.063 and 0.787, respectively), although litter size (0.92, 1.21, 1.17, 1.86, 1.12, and 1.82; SEM = 0.221) and total litter birth weight (5.84, 5.74, 5.92, 7.52, 5.04, and 6.78 kg for DOR-LS, DOR-HS, KAT-LS, KAT-HS, STC-LS, and STC-HS, respectively; SEM = 0.529) were greater (p < 0.05) for HS than for LS. In conclusion, although there was some compensation in wheat straw intake for the different levels of supplementation, soybean meal given alone rather than with cereal grain adversely affected BW, BCS, BMI, and reproductive performance, the latter primarily through litter size but also via a trend for an effect on the birth rate. Hence, the supplementation of low-protein and high-fiber forage such as wheat straw should include a consideration of the inclusion of a feedstuff(s) high in energy in addition to nitrogen.