Comparison of models for lactation curves of Holstein, Brown Swiss, and F1 crossbred cows under subtropical conditions.

Tropical and subtropical milk production herds in Mexico generally generate different types of milk-yield records as milk yield per month and mean production per month. Lactation curves generated by these types of records may contribute to understand milk production in the tropical regions of Mexico. The aim of this study was to compare five lactation-curve models fitted to two types of milk-yield records of Holstein, Brown Swiss, and F1 crossbred cows under subtropical conditions. The two types of records (n = 3756) used were: (1) milk yield per month (TR) and 2) mean production per months (MR). Goodness-of-fit statistics, including Akaike's information criterion (AIC) and root mean square error (RMSE), were applied to compare the models for each type of records. The Brody model provided the best goodness-of-fit when using monthly milk-yield records, while the Wilmink model provided the best goodness-of-fit for lactation milk-yield records. The RMSE and AIC values were similar between datasets. The final third of the lactation curve showed a little difference between model predictions in both datasets. The comparison of several models was useful to better describe the actual lactation curves of the herd. The Wood model may be adequate to compare information as a reference with other models for decision making process at milk production.

Ancient Mitogenomes Reveal the Evolutionary History and Biogeography of Sloths.

Living sloths represent two distinct lineages of small-sized mammals that independently evolved arboreality from terrestrial ancestors. The six extant species are the survivors of an evolutionary radiation marked by the extinction of large terrestrial forms at the end of the Quaternary. Until now, sloth evolutionary history has mainly been reconstructed from phylogenetic analyses of morphological characters. Here, we used ancient DNA methods to successfully sequence 10 extinct sloth mitogenomes encompassing all major lineages. This includes the iconic continental ground sloths Megatherium, Megalonyx, Mylodon, and Nothrotheriops and the smaller endemic Caribbean sloths Parocnus and Acratocnus. Phylogenetic analyses identify eight distinct lineages grouped in three well-supported clades, whose interrelationships are markedly incongruent with the currently accepted morphological topology. We show that recently extinct Caribbean sloths have a single origin but comprise two highly divergent lineages that are not directly related to living two-fingered sloths, which instead group with Mylodon. Moreover, living three-fingered sloths do not represent the sister group to all other sloths but are nested within a clade of extinct ground sloths including Megatherium, Megalonyx, and Nothrotheriops. Molecular dating also reveals that the eight newly recognized sloth families all originated between 36 and 28 million years ago (mya). The early divergence of recently extinct Caribbean sloths around 35 mya is consistent with the debated GAARlandia hypothesis postulating the existence at that time of a biogeographic connection between northern South America and the Greater Antilles. This new molecular phylogeny has major implications for reinterpreting sloth morphological evolution, biogeography, and diversification history.

Ancient parasitic DNA reveals Toxascaris leonina presence in Final Pleistocene of South America.

Parasitological analysis of coprolites has allowed exploring ecological relationships in ancient times. Ancient DNA analysis contributes to the identification of coprolites and their parasites. Pleistocene mammalian carnivore coprolites were recovered from paleontological and archaeological site Peñas de las Trampas 1.1 in the southern Puna of Argentina. With the aim of exploring ancient ecological relationships, parasitological analysis was performed to one of them, dated to 16 573-17 002 calibrated years BP, with 95.4% probability. Parasite eggs attributed to Toxascaris sp. by morphological characters were isolated. DNA of coprolite and eggs was extracted to molecular identification. Ancient mitochondrial DNA analysis confirmed the zoological origin of the coprolite as Puma concolor and that of parasite eggs as Toxascaris leonina. This is the oldest molecular parasite record worldwide, and it supports the presence of this parasite since the Pleistocene in America. These findings have implications for the biogeographic history of parasites and for the natural history of the region.

Collagen Sequence Analysis of the Extinct Giant Ground Sloths Lestodon and Megatherium.

For over 200 years, fossils of bizarre extinct creatures have been described from the Americas that have ranged from giant ground sloths to the 'native' South American ungulates, groups of mammals that evolved in relative isolation on South America. Ground sloths belong to the South American xenarthrans, a group with modern although morphologically and ecologically very different representatives (anteaters, armadillos and sloths), which has been proposed to be one of the four main eutherian clades. Recently, proteomics analyses of bone collagen have recently been used to yield a molecular phylogeny for a range of mammals including the unusual 'Malagasy aardvark' shown to be most closely related to the afrotherian tenrecs, and the south American ungulates supporting their morphological association with condylarths. However, proteomics results generate partial sequence information that could impact upon the phylogenetic placement that has not been appropriately tested. For comparison, this paper examines the phylogenetic potential of proteomics-based sequencing through the analysis of collagen extracted from two extinct giant ground sloths, Lestodon and Megatherium. The ground sloths were placed as sister taxa to extant sloths, but with a closer relationship between Lestodon and the extant sloths than the basal Megatherium. These results highlight that proteomics methods could yield plausible phylogenies that share similarities with other methods, but have the potential to be more useful in fossils beyond the limits of ancient DNA survival.

Ticks (Acari: Argasidae, Ixodidae) from Middle and pre-Hispanic Late Holocene associated with human activities in northwestern Argentina.

One male of Amblyomma parvitarsum and one male and a female of Ornithodoros sp. were recovered from archaeological layers of the Middle Holocene in a rock shelter in the province of Catamarca, used by hunter-gatherer groups. Another two ticks identified as a female and a nymph of Argas cf. neghmei were recovered from a layer of the Late Holocene in other rock shelter in the province of Tucumán used by humans of agro-pastoral complex societies previous to the Hispanic invasion. The presence of Amblyomma parvitarsum is probably related to hunting activity, while Ornithodoros sp. was probably an opportunistic parasite established in the shelter. Argas cf. neghmei was probably a parasite of birds as is A. neghmei, a tick that has been found in the nests of birds, chicken houses, but also in human dwellings. The presence of A. cf. neghmei may originate from birds naturally breeding in the shelter or from the nests of birds introduced into the shelter by humans.

Caso de miasis orbitaria / A case of myasis orbitalis

Se presenta un caso de un paciente masculino de ochenta y tres años de edad, de raza blanca con antecedentes de la enfermedad del Parkinson con una miasis orbitaria derecha profunda producida por el gusano barrenador de la mosca Cochlimyia hominivorax. Se realizó un reporte de caso con el objetivo de describir el cuadro médico que presentaba el anciano. Presentó abundantes larvas en una zona necrótica en el párpado superior derecho, con fetidez y ninguna sensación en la zona que permitió realizar la toilette de urgencia sin el uso de ningún anestésico. Se interconsultó por un conjunto de especialistas de diferentes materias y se determinó que la mejor opción era la enucleación del globo ocular y necrectomía de la zona afectada junto a una etmoidectomía con el objetivo de eliminar la mayor cantidad de larvas posible. El paciente luego de operado evolucionó favorablemente.

A case of an eighty three year-old, white race, masculine patient, with antecedents of Parkinson´s disease is presented with a deep right myasis orbitalis produced by the borer worm of the Cochlimyia hominivorax fly. The clinical picture is described, abundant larvae in a necrotic area of the right upper eyelid, with fetidity and no sensation that allowed to carry out the toilette of urgency without the use of any anesthetic. He was interconsulted by a group of specialists of different matters and it was determined that the best option was the enucleation of the eyeball and necrectomy of the affected area next to an ethmoidectomy with the objective of eliminating the biggest quantity of larvae. The patient after been operated evolved favorably.

Caso de miasis orbitaria / A case of myasis orbitalis

Se presenta un caso de un paciente masculino de ochenta y tres años de edad, de raza blanca con antecedentes de la enfermedad del Parkinson con una miasis orbitaria derecha profunda producida por el gusano barrenador de la mosca Cochlimyia hominivorax. Se realizó un reporte de caso con el objetivo de describir el cuadro médico que presentaba el anciano. Presentó abundantes larvas en una zona necrótica en el párpado superior derecho, con fetidez y ninguna sensación en la zona que permitió realizar la toilette de urgencia sin el uso de ningún anestésico. Se interconsultó por un conjunto de especialistas de diferentes materias y se determinó que la mejor opción era la enucleación del globo ocular y necrectomía de la zona afectada junto a una etmoidectomía con el objetivo de eliminar la mayor cantidad de larvas posible. El paciente luego de operado evolucionó favorablemente (AU)

A case of an eighty three year-old, white race, masculine patient, with antecedents of Parkinson´s disease is presented with a deep right myasis orbitalis produced by the borer worm of the Cochlimyia hominivorax fly. The clinical picture is described, abundant larvae in a necrotic area of the right upper eyelid, with fetidity and no sensation that allowed to carry out the toilette of urgency without the use of any anesthetic. He was interconsulted by a group of specialists of different matters and it was determined that the best option was the enucleation of the eyeball and necrectomy of the affected area next to an ethmoidectomy with the objective of eliminating the biggest quantity of larvae. The patient after been operated evolved favorably (AU)