Fiber quality and fertility in male alpacas in the Cusco region of Peru

Introduction

High testosterone levels might be associated with coarser fiber in alpacas, affecting fiber quality. In the husbandry systems employed in the Andes, males with higher libido might have an increased frequency of successful matings than males with lower libido. This study aimed to determine some of the factors affecting fiber quality in Peruvian alpacas and to evaluate the association between fiber quality and male mating behavior.

Methods

The study population consisted of 189 adult male alpacas at La Raya, Cusco, Peru, at 4,400 m above sea level, belonging to the National University of San Marcos, Lima, and the National University of San Antonio Abad of Cusco. Fiber samples were collected from male alpacas in September 2015; body condition score (BCS) was evaluated. After washing and drying, the fiber samples were analyzed using an Optical Fiber Diameter Analyser 2000; linear regression analysis between predictor variables (location of alpacas, age, BCS, and fiber color) and fiber quality outcomes was conducted. Fertility data were available only for some males belonging to San Marcos University, consisting of hand-written records from the breeding season January to April 2015; individual fertility quotients were calculated for each male.

Results

Age was associated with fiber quality, young alpacas having the finest fibers (p < 0.05). An increased BCS was associated with increased fiber length, fiber diameter and spinning fineness, but decreased comfort factor (p < 0.05). White fibers were thinner (p = 0.05) than colored fibers, with lower comfort factor and spinning fineness. A significant association between the fertility quotient and fiber curvature was observed (p = 0.018).

Discussion

These results suggest that careful selection of breeding individuals and attention to husbandry could result in improved fiber quality among alpaca herds in Peru. However, it would be advisable to increase the number of males studied, using more reliable methods for evaluating male fertility and pregnancy diagnosis than were available for this study.

Roan coat color in livestock

Since domestication, a wide variety of phenotypes including coat color variation has developed in livestock. This variation is mostly based on selective breeding. During the beginning of selective breeding, potential negative consequences did not become immediately evident due to low frequencies of homozygous animals and have been occasionally neglected. However, numerous studies of coat color genetics have been carried out over more than a century and, meanwhile, pleiotropic effects for several coat color genes, including disorders of even lethal impact, were described. Similar coat color phenotypes can often be found across species, caused either by conserved genes or by different genes. Even in the same species, more than one gene could cause the same or similar coat color phenotype. The roan coat color in livestock species is characterized by a mixture of white and colored hair in cattle, pig, sheep, goat, alpaca, and horse. So far, the genetic background of this phenotype is not fully understood, but KIT and its ligand KITLG (MGF) are major candidate genes in livestock species. For some of these species, pleiotropic effects such as subfertility in homozygous roan cattle or homozygous embryonic lethality in certain horse breeds have been described. This review aims to point out the similarities and differences of the roan phenotype across the following livestock species: cattle, pig, sheep, goat, alpaca, and horse; and provides the current state of knowledge on genetic background and pleiotropic effects.

Variation in Wool Characteristics across the Body in a Herd of Alpacas Kept in Poland

Simple Summary

Alpaca wool is luxurious and, hence, arouses great interest among consumers. However, the drawbacks of this wool are its variation in thickness and the proportion of medullated fibers. Knowing about variations in the quality characteristics of the wool on an animal’s body can help in properly evaluating and using this wool. This study has shown that the wool from the belly, front and hind legs, and the neck need to be separated from the total fleece. The most appropriate site from where to collect a representative sample of wool from the fleece for testing purposes is at the midside of the animal.

Abstract

Wool characteristics vary depending on where on the body the wool is produced. Knowledge of this variation is important in order to separate the fleece into more homogenous parts. Similar parts from different animals can then be pooled to create batches of wool with similar characteristics. This will allow for better alpaca products with less variation. The aim of this study was to determine the variation in fiber diameter, medullation, and staple length across the body of alpacas from one herd. Wool samples were collected from 16 adult (3–5 years old) females: from the saddle (S), midside (MS), neck (N), and pieces (P). The mean fiber diameter (MFD) and medullation were measured using a projection microscope according to the IWTO-8-2011 standard. The fiber diameter of the pieces was greater (p < 0.05) than for the S, MS, and N areas. The highest medullation was found on the neck. The neck was also characterized by the shortest wool. The MFD for the fleece, excluding P, showed the strongest correlation (r = 0.927) with the MFD of MS. The study showed that due to the variation of fiber diameter, the incidence of medullation, and staple length, the wool from the pieces and the neck should be separated from the total fleece. The most appropriate site from where to collect a representative sample of wool from the fleece for testing purposes is the midside site of the animal.

Analysis of the wool thickness and medullation characteristics based on sex and color in a herd of alpacas in Poland

The objective of this study was to analyze the thickness and medullation characteristics of the wool of a herd of Huacaya alpacas kept in Poland. Wool samples were collected from 36 adult alpacas, including 22 females and 14 males. Light (15 animals) and dark (21 animals) color varieties of wool were considered in this research. A projection microscope was used to measure the fiber diameter and assess the medullation. Each fiber was categorized according to the medulla as a non-medullated, discontinuous medullated or continuous medullated fiber. The mean fiber diameter (MFD), standard deviation (SD), coefficient of variation (CV), comfort factor (CF) and prickling factor (PF) were determined for each sample. The MFD, SD and CV were also determined for the abovementioned fiber categories. The mean fiber diameter of all alpacas tested was 25.31  µ m . The CF and PF were 77.79 % and 22.21 %, respectively. The medullation percentage in the wool of the study alpacas was 68.91 %. The mean fiber diameter was larger in males ( P < 0.05 ) than in females. There were no differences between males and females in terms of the proportion of fibers with a diameter  <  30  µ m (CF) and  >  30  µ m (PF). The non-medullated fibers in the wool of females were thinner ( P < 0.05 ) than in the wool of males. The wool of males also had a larger degree of medullation. Light wool was thinner ( P < 0.05 ) than dark wool. The discontinuous and the continuous medullated fibers were thicker ( P < 0.05 ) in dark wool than in light wool. In dark wool, the share of discontinuous fibers was higher ( P < 0.05 ) and the share of the non-medullated fibers was lower ( P < 0.05 ) than in light wool. The presence of various types of medulla or the absence of medulla was noted in fibers with smaller and larger diameters, regardless of the sex of the animals or the color of the wool.

Camelids: new players in the international animal production context

The Camelidae family comprises the Bactrian camel (Camelus bactrianus), the dromedary camel (Camelus dromedarius), and four species of South American camelids: llama (Lama glama), alpaca (Lama pacos) guanaco (Lama guanicoe), and vicuña (Vicugna vicugna). The main characteristic of these species is their ability to cope with either hard climatic conditions like those found in arid regions (Bactrian and dromedary camels) or high-altitude landscapes like those found in South America (South American camelids). Because of such interesting physiological and adaptive traits, the interest for these animals as livestock species has increased considerably over the last years. In general, the main animal products obtained from these animals are meat, milk, and hair fiber, although they are also used for races and work among other activities. In the near future, climate change will likely decrease agricultural areas for animal production worldwide, particularly in the tropics and subtropics where competition with crops for human consumption is a major problem already. In such conditions, extensive animal production could be limited in some extent to semi-arid rangelands, subjected to periodical draughts and erratic patterns of rainfall, severely affecting conventional livestock production, namely cattle and sheep. In the tropics and subtropics, camelids may become an important protein source for humans. This article aims to review some of the recent literature about the meat, milk, and hair fiber production in the six existing camelid species highlighting their benefits and drawbacks, overall contributing to the development of camelid production in the framework of food security.

Identification and characterization of microRNAs in white and brown alpaca skin

AB BACKGROUND: MicroRNAs (miRNAs) are small, non-coding 21-25 nt RNA molecules that play an important role in regulating gene expression. Little is known about the expression profiles and functions of miRNAs in skin and their role in pigmentation. Alpacas have more than 22 natural coat colors, more than any other fiber producing species. To better understand the role of miRNAs in control of coat color we performed a comprehensive analysis of miRNA expression profiles in skin of white versus brown alpacas.

RESULTS

Two small RNA libraries from white alpaca (WA) and brown alpaca (BA) skin were sequenced with the aid of Illumina sequencing technology. 272 and 267 conserved miRNAs were obtained from the WA and BA skin libraries, respectively. Of these conserved miRNAs, 35 and 13 were more abundant in WA and BA skin, respectively. The targets of these miRNAs were predicted and grouped based on Gene Ontology and KEGG pathway analysis. Many predicted target genes for these miRNAs are involved in the melanogenesis pathway controlling pigmentation. In addition to the conserved miRNAs, we also obtained 22 potentially novel miRNAs from the WA and BA skin libraries.

CONCLUSION

This study represents the first comprehensive survey of miRNAs expressed in skin of animals of different coat colors by deep sequencing analysis. We discovered a collection of miRNAs that are differentially expressed in WA and BA skin. The results suggest important potential functions of miRNAs in coat color regulation.

Wool characteristics in the third generation of Arkharmerino × Ghezel and Arkharmerino × Moghani crossbreed sheep

This investigation was conducted to evaluate the comparative productive performances and effect of some environmental factors on wool characteristics of Arkharmerino × Ghezel (Ar × Gh) and Arkharmerino × Moghani (Ar × Mo) crossbreed sheep. The mid-side fleece samples taken from animals during 2 years (2007-2008) were analyzed. Each sample was measured for average fiber diameter, fiber diameter variability, staple length, proportion of medullated fiber, proportion of kemp, and comfort factor. The comparative values for these fleece characteristics in F(3) generation Ar × Gh were 28.78 ± 0.48 μm, 36.84 ± 1.16%, 11.94 ± 0.35 cm, 7.07 ± 0.93%, 1.02 ± 0.23%, and 68.93%, respectively; while those traits were 29.79 ± 0.43 μm, 41.86 ± 1.16%, 11.96 ± 0.37 cm, 8.13 ± 1.06%, 2.71 ± 0.45%, and 63.33 ± 3.66% for Ar × Mo, respectively. The effects of genotype, sex, birth type, and year of birth were analyzed. Genotype had a significant (P < 0.01) effect on average fiber diameter and proportion of kemp, and Ar × Gh crossbreeds had lower diameter with less proportion of kemp. The two differences in fiber characteristics that were attributable to sex were fiber diameter variability and proportion of medullated fiber, and females had higher measure than males for both traits. Statistical analysis showed that crossbreeding with Arkharmerino generally had positive effects on the fleece favored to be used in the hand woven authentic carpet production.

Blood mineral, trace-element and vitamin concentrations in Huacaya alpacas and Merino sheep grazing the same pasture

We aimed to determine whether the concentration of minerals and trace constituents in blood of Merino sheep and Huacaya alpacas grazing the same pasture differed with species and time of sampling. Blood samples and pasture samples were collected at frequent intervals over a period of 2 years for mineral and trace-nutrient assay. The concentration of the minerals and trace nutrients in the grazed pasture usually met the dietary needs of sheep at maintenance, apart from potassium, sulfur, cobalt and Vitamin E in occasional samples. Restricted maximum likelihood mixed model analysis indicated a significant (P < 0.001) species by month by year interaction for all blood constituents assayed, a significant (P < 0.05) species by coat shade interaction for plasma Vitamin D, E and B12 and a significant (P < 0.001) species by month by Vitamin D interaction for plasma phosphorus concentrations. In general, plasma calcium concentrations were greater in sheep than in alpacas but plasma magnesium concentrations were greater in alpacas than in sheep. There was no consistent difference between the two species in plasma phosphorus concentrations although low values were recorded in individual sheep and alpacas. Plasma Vitamin D concentrations were more responsive to increasing hours of sunlight in alpacas than they were in sheep. Sheep had consistently higher concentrations of plasma copper, zinc and Vitamin B12 and higher concentrations of blood selenium but lower concentrations of plasma selenium and Vitamin A, than did alpacas. No consistent difference was observed between the two species in plasma Vitamin E concentrations.

Producción de fibra de alpaca, llama, vicuña y guanaco en Sudamérica

Más de un millón de pequeños productores de los Andes centrales de Sudamérica tienen alpacas (Vicugna pacos) y llamas (Lama glama) como principal medio de subsistencia. Los animales proveen carne, leche, fibra, energía de transporte y guano y, además, son un elemento importante de la identidad cultural de sus pueblos. Con 3,9 millones de llamas y 3,3 millones de alpacas la producción total de fibras de camélidos en la región supera los 5 millones de kg anuales. Cerca del 30% de la producción de fibra se transforma y es usada a nivel de predio o comunidad. Alrededor del 80% de la alpaca comercializada es de color blanco y el 12% tiene diámetros de fibra menores de 23 micrones. Las fibras de llama son de menor valor y más variables en colores y diámetros que las fibras de alpaca. Ambas especies tienen dos razas, cada una con características de calidad de fibra y adaptación específica. También existen en Sudamérica dos especies de camélidos silvestres, el guanaco (Lama guanicoe) y la vicuña (Vicugna vicugna). Ambas tienen vellones de valiosa fibra down. Poblaciones específicas de estos camélidos califican para ser capturadas, esquiladas y liberadas generando un ingreso adicional a las comunidades en que viven. El aumento de la producción de fibras y demás productos de los camélidos sudamericanos, a la vez de preservar un recurso genético animal crítico y los valores culturales asociados y mejorar la calidad de vida de muchos pequeños productores, debe ser parte de una estrategia global de inversión sostenida en investigación y desarrollo apropiados.

Factors associated with low vitamin D status of Australian alpacas

OBJECTIVE

To investigate factors associated with low vitamin D status of alpacas at pasture in southern Australia.

DESIGN

A 2-year survey of alpacas from two farms in South Australia and three in Victoria. Blood samples were collected from 20 to 30 alpacas on each farm on five occasions each year. Breed, gender, age and fleece colour of animals were recorded.

METHOD

Blood samples were assayed for plasma 2.5-hydroxycholecalciferol (25-OH D(3)) and plasma inorganic phosphorus (Pi). Data sets from 802 animal samples were analysed by multiple regression to determine variables associated with low vitamin D status of alpacas. The relationship between plasma 25-OH D(3) and plasma Pi was also investigated.

RESULTS

Vitamin D status was significantly affected by month of sampling, with low values in late winter and high values in summer. Plasma vitamin D concentrations increased with age, were higher in alpacas with light fleeces than in those with dark fleeces and were also higher in the Suri than in the Huacaya breed. Plasma Pi concentrations were generally lower in alpacas with plasma 25-OH D(3) values < 25 nmol/L.

CONCLUSIONS

Young alpacas with dark fleeces are most at risk from vitamin D insufficiency in late winter in southern Australia. The present study indicates that plasma Pi values are not a reliable indicator of vitamin D status of alpacas as assessed by plasma 25-OH D(3) concentrations.