Commercial Hair Analysis in Horses: A Tool to Assess Mineral Intake?

The use of hair samples to assess the mineral intake of horses under practical conditions has recently been attracting increased interest. The aims of this study were to compare mineral analysis results in equine mane hair between three commercial laboratories and to determine the relationship between the mineral intake and mineral content in mane hair. Four warmblood horses (14 ± 3 years) were included in the study. Horses were fed hay ad libitum and a commercial mineral supplement to meet nutrient requirements under maintenance conditions. Mane hair from the hairline was collected with a sample length of 2 to 3 cm according to the respective laboratory guidelines to monitor the feeding period of the last 1 to 2 months. Minerals in mane hair were analyzed by three commercial laboratories using inductively coupled plasma mass spectrometry (ICP-MS) or inductively coupled plasma optical emission spectroscopy and in feedstuffs using ICP-MS to calculate mineral intake. Hair mineral analysis showed that the results and their corresponding reference ranges widely varied among the three laboratories. The mean coefficient of variance ranged from a minimum of 10% for selenium (Se) to a maximum of 58% for iron (Fe). For example, Se supply (requirement, 1.17-1.28 mg/d; intake, 1.83 mg/d) was considered insufficient in all horses by two laboratories, whereas it was considered adequate by one laboratory. Intervariation of the same sample, as well as differences in reference ranges, was considerably high among the three laboratories. These results indicate that hair mineral analysis is not reliable for assessing mineral intake in horses.

Evaluation of hair analysis for determination of trace mineral status and exposure to toxic heavy metals in horses in the Netherlands.

Analysis of hair to gain insight into the trace mineral status and exposure to toxic heavy metals of horses is attractive because hair is an easily accessible sample material. To investigate the potential value of hair analysis in horses for determination of trace mineral and heavy metal concentrations, we analyzed mane hair and liver samples from 62 horses presented for slaughter at a facility in the Netherlands that receives horses from all regions of the country. Hair samples were cleaned in warm water. After acid digestion of hair and liver specimens, we quantified, with inductively coupled plasma-mass spectrometry, arsenic, cadmium, chromium, cobalt, copper, iron, lead, manganese, molybdenum, nickel, selenium, vanadium, and zinc in the digests. Based on Pearson product moment correlations, we found no statistically significant correlations between concentrations of trace minerals in liver and hair, with the exception of a slight correlation for copper that was too weak to be of clinical relevance. Our results do not support the use of hair to determine trace mineral status and exposure to toxic heavy metals in the horse under field conditions.

Use of the cryostat to prepare slides for trichological analysis / [Uso do aparelho criostato para preparação de lâminas para a análise tricológica]

A análise dos padrões morfológicos e morfométricos das microestruturas capilares é uma técnica não invasiva que pode ser utilizada para identificar espécies de mamíferos. Esta técnica pode ser aplicada em diversas áreas da ciência animal, tais como controle de qualidade de alimentos e análises forenses. Dada a dificuldade de obter seções transversais de pelos de guarda para expor o córtex, a maioria dos estudos analisou apenas os componentes medulares e cuticulares do pelo. A inclusão do córtex capilar de guarda em uma análise tricológica pode proporcionar uma descrição mais precisa das raças ou espécies de mamíferos. O presente estudo propõe um novo método para a execução de cortes transversais que expõem o córtex do pelo guarda de mamíferos utilizando um criostato.(AU)

Comparative growth response related to hair mineral analysis in dromedary camel calves.

Background: The dromedary camel plays a significant role in supporting the livelihood of pastoral and agropastoral systems, as well as a source of income for the national economy in arid regions. Aim: The current study was executed to check the comparative growth response in relation to hair mineral status in Marecha camel calves reared under an intensive management system and an extensive management system in Thal desert Punjab, Pakistan. Methods: Twelve male and female Camelus dromedarius calves of almost the same weight and age were divided into two groups of 6 each (3 male and 3 female). The calves of the first group were maintained at the Camel Breeding and Research Station, Rakh Mahni, in a semi-open housing system, while the second group was maintained in available housing under field conditions. Calves in the first group were fed concentrate at the rate of 1 kg/head/day along with gram straw (Cicer arientinum) ad libitum, while calves in the second group were allowed to graze/browse for 10 hours daily along with household refusals, including kitchen wastes. Water was provided twice a day. Impressum's digital weighing scale was used for fortnightly weighing. Data collected on different parameters were subjected to statistical analysis with 2 × 2 factorial arrangements of treatments under a completely randomized design. Results: After the 120-day trial period, the mean body weight and average daily gain of male and female calves were significantly increased (p < 0.05) in IMS as 80.8 ± 2.7, 77.8 ± 2.7 kg and 0.67 ± 0.02, 0.65 ± 0.02 kg/days than EMS as 64.5 ± 2.6, 52.9 ± 2.6 kg and 0.54 ± 0.02, 0.44 ± 0.02 kg/days. Intake of crop residues (p < 0.05) was found to be 6.9 ± 0.45 and 6.4 ± 0.45 kg/days for male and female calves in IMS, respectively, and 3.5 ± 0.23 for male and female calves in EMS, respectively. The conversion index g/kg average daily intake was 97.1, 101.5 and 154.3, 125.7 for male and female calves in IMS and EMS, respectively. Regarding hair mineral status, Ca, Mg, Cu, Zn, Fe, and Mn concentrations were found to be significantly different (p < 0.05) among calf groups in IMS and EMS. Conclusion: This study indicates that wool analysis and management of weight gain in camel calves should be further explored to support increased meat supply in arid regions.