ABSTRACT
Burgeoning pressures of habitat loss is a major cause of herbivore decline across India, forcing them to coexist with humans in non-protected areas. Their conservation in such landscapes is challenging due to paucity of ecological and demographic information. The northern subspecies of swamp deer, Rucervus duvaucelii duvaucelii, is one such herbivore that lives across human dominated landscapes in Terai region and upper Gangetic plains of north India. Here, we describe species-specific molecular markers and a cervid-specific molecular sexing assay for swamp deer and four other coexisting cervids sambar, chital, barking deer and hog deer. Our markers show species-specific band patterns and a high success rate of 88.21% in large number of field collected referencesamples for all species. Faecal pellets from pilot swamp deer survey samples from upper Ganges basin show 93.81% success rate, and only 5.5% misidentification based on morphological characteristics. Our cervid-specific molecular sexing multiplex assay accurately ascertained 81.15% samples to respective sexes. These molecular approaches provide an easy, quick and cheap option to generate critical information on herbivore population parameters and aid their conservation in this mosaic of protected and non-protected grassland habitats.
ABSTRACT
The Chinese softshell turtle exhibits ZZ/ZW sex determination. To identify the sex of embryos, juvenile and adult individuals, we designed two pairs of polymerase chain reaction primers, SB1-196, which amplifies a fragment of 196 bp in the female and the other, CK1-482, which amplifies the 482-bp fragment in both the sexes. It is validated in 24 adult turtles of known sex, sampled from three different locations. This one-step sexing technique is rapid and easy to perform and is reported for the first time.
ABSTRACT
The Brazilian tanager, Ramphocelus bresilius is an endemic species from Brazil that is sexually dimorphic in adult plumage. Young males are similar to adult and young females until their second year. Adults and young females are not distinguishable in plumage. We tested whether iris colour can be used to separate adult females from immature females. We used for the first time the molecular sexing technique based on CHD-genes to confirm the sex of the individuals classified as "female plumage with red iris", and to identify the sex of individuals classified as "female plumage and brown iris". The adult males were used as a positive control. DNA samples from 190 individuals were analysed. The sizes of the PCR products were identified as 350 base pairs (bp) for CHD-Z and 388 bp for CHD-W. We confirmed that adult females have a red iris and the young females a brown iris. We could also separate young males and females which present the same iris colour and plumage. Although there are indications that the iris colour can be used by birds to identify the adults in co-operative breeding species such as the Brazilian tanager, more behavioural data are required to understand the role of iris coloration in this species. Rev. Biol. Trop. 56 (4): 1629-1633. Epub 2008 December 12.
El ave Ramphocelus bresilius es una especie endémica de Brasil con dimorfismo sexual en el plumaje del adulto. Los machos jóvenes son similares a las hembras adultas y jóvenes hasta el segundo año de vida. Adultos y hembras jóvenes son indistinguibles por el plumaje. Evaluamos si el color del iris puede ser utilizado para distinguir hembras adultas de hembras inmaduras. Utilizamos por primera vez la técnica molecular de identificación de sexos basada en los genes CHD para confirmar el género de individuos clasificados como plumaje femenino con iris rojo, y para identificar el sexo de los individuos clasificados como plumaje femenino e iris marrón. Usamos machos adultos como control. Analizamos muestras de DNA de 190 individuos. Los tamaños de los productos del PCR fueron identificados como 350 pares de bases (pb) para CHD-Z y 388 pb para CHD-W. Pudimos confirmar que las hembras adultas presentan iris rojo y las hembras jóvenes iris marrón. También pudimos distinguir machos jóvenes de hembras, que presentan el mismo color de iris y plumaje.