Semi-arid regions with little surface water commonly experience rapid water table decline rates. To hedge against the falling water table, production wells in central Mexico are commonly installed to depths of several hundred meters below the present water table and constructed as open boreholes or perforated casings across their entire length. Such wells represent highly conductive pathways leading to non-negligible flow across chemically distinct layers of an aquifer-a phenomenon known as ambient flow.
View Article and Find Full Text PDFThe present experiments on goats were conducted with the aim of verifying (a) whether the identity of the goat kids can affect the characteristics of milk let-down during suckling (Study 1) and (b) whether the presence of the goat kids may improve the milk let-down during hand milking (Study 2). In Study 1, 16 lactating goats with twins and 12 with single kids were used. Dams with single goat kids ejected more milk when suckling their kids at Days 5 and 20 of lactation, than when suckling aliens.
View Article and Find Full Text PDFThis study examines the effectiveness of the photoperiod treatment (extra light for 88 days) to render the bucks sexually active during the seasonal anoestrous in order to induce a male effect, depending on the reproductive seasonality of the breed of the bucks used. In April, 57 anoestrous Blanca Andaluza does were distributed into four groups with three males each: 13 were exposed to control Murciano-Granadina bucks (lower seasonality); 15 were exposed to photostimulated Murciano-Granadina bucks; 14 were exposed to control Blanca Andaluza bucks (higher seasonality), and 15 were exposed to photostimulated Blanca Andaluza bucks. After male introduction, the sexual behaviour of the bucks was assessed, and harness marks recorded doe oestrous behaviour.
View Article and Find Full Text PDFThis study identifies causes of rising arsenic (As) concentrations over 17 years in an inter-montane aquifer system located just north of the Trans-Mexican-Volcanic-Belt in the Mesa central physiographic region that is extensively developed by long-screened production wells. Arsenic concentrations increased by more than 10 µg/L in 14% (3/22) of re-sampled wells. Similarly, in a larger scale analysis wherein As concentrations measured in 137 wells in 2016 were compared to interpolated, baseline concentrations from 246 wells in 1999, As concentrations rose more than 10 µg/L in 30% of wells.
View Article and Find Full Text PDFThis research communication addresses the hypothesis that in dual-purpose goats, exposure to 1 h of extra-light given from 16 to 17 h after dawn (pulse of light) in winter stimulates milk yield. One group of goats was maintained under natural short photoperiod (natural day; ND (n = 7)). Another group of lactating females was submitted to an artificial long-day photoperiod consisting of 16 h light and 8 h darkness (long days; LD (n = 7)).
View Article and Find Full Text PDFIn this study, two empirical correlations of the Nusselt number, based on two artificial neural networks (ANN), were developed to determine the heat transfer coefficients for each section of a vertical helical double-pipe evaporator with water as the working fluid. Each ANN was obtained using an experimental database of 1109 values obtained from an evaporator coupled to an absorption heat transformer with energy recycling. The Nusselt number in the annular section was estimated based on the modified Wilson plot method solved by an ANN.
View Article and Find Full Text PDFFluoride (F), naturally found in aquifers around the world at toxic concentrations, causes disease in millions of people. The long-term stability, however, of those concentrations within intensively pumped aquifers is poorly characterized. We assessed long-term stability in the spatial distribution of F concentrations in an intensively pumped aquifer within the semi-arid, inter-montane Independence Basin in central Mexico between 1999 and 2016.
View Article and Find Full Text PDFThis study was designed to determine whether any relationship exists between exposure to artificial long days, milk yield, maternal plasma insulin-like growth factor 1 (IGF-1) levels, and kid growth rate in goats. One group of lactating goats was maintained under naturally decreasing day length (control group; n = 19), while in another one, they were kept under artificial long days (LD group; n = 19). Milk yield was higher in goats from the LD group than that in the control group (P < 0.
View Article and Find Full Text PDFIn seasonally anovulatory goats, daily contact with photostimulated bucks for 15 days stimulates ovulations in most females. In this study, we determined whether ovulation could be induced in goats exposed to photostimulated bucks for less than 15 days. Bucks were rendered sexually active during the nonbreeding season by exposure to 2.
View Article and Find Full Text PDFBackground: To describe the characteristics of patients ≤40 years of age hospitalized for acute coronary syndrome, analyze the risk factors and identify the variables associated with prognosis.
Methods: Case series of patients admitted between 2003 and 2012 inclusive in a tertiary hospital (123 consecutive cases admitted between 2003 and 2012), and case-control study (369 controls selected from the general population matched for sex and age with cases, at a ratio of 3:1).
Outcome Variables: Mortality, likelihood of survival without readmission for heart-related problems, extent of coronary disease as determined by coronary angiography and cardiovascular risk factors.
We investigated whether live vocalizations emitted by bucks interacting with anestrous females stimulate secretion of LH, estrous behavior and ovulation in anestrous goats. In experiment 1, bucks rendered sexually active by exposure to long days followed by natural photoperiod were exposed in a light-proof-building to five anestrous females. Buck vocalizations were reproduced through a microphone-amplifier-loudspeaker system to an open pen where one group of goats (n=6) was exposed for 10 days to these live vocalizations.
View Article and Find Full Text PDFWe investigated whether LH secretion, estrous behavior and fertility would differ between sexually inexperienced and experienced anestrous goats exposed to the males. Male goats were rendered sexually active during the reproductive rest season by exposure to 2.5 months of artificial long days.
View Article and Find Full Text PDFMaternal behavior in the goat appears at the time of parturition, partly under the activating influence of vaginocervical stimulation. Mothers actively lick their neonate and rapidly establish a selective bond with their kid through olfactory recognition. They also develop visual and acoustic recognition of the kid within 4 h following birth.
View Article and Find Full Text PDFUnder temperate and subtropical latitudes, ewes and goats display a reproductive seasonal pattern and their sexual activity during the anestrous period can be stimulated and synchronized by the introduction of males in the group, which is called the "male effect". The response of females to the male effect in the middle of the anestrous season is weak or absent. This failure may be due to the inability of the female to respond to males, as a result of a refractoriness of the female to the male stimulus.
View Article and Find Full Text PDFParturient goats rapidly develop exclusive nursing of their own litter that relies on olfactory recognition of the young. They also show a period of postpartum anoestrus whose duration depends on the presence of the kid. In cattle, maternal selectivity is one of the factors that delays the recovery of sexual activity.
View Article and Find Full Text PDFReproductive seasonality is observed in some breeds originating from or adapted to subtropical latitudes. In 'photoperiodic flexible breeds', such as Australian cashmere goats, the annual breeding season can be manipulated through nutrition, whereas in 'photoperiodic rigid breeds', such as Creole goats from subtropical Mexico, sexual activity can be controlled by altering the photoperiod. In males from the latter breed, artificial long days, whether or not accompanied by the administration of melatonin, stimulate sexual activity during the non-breeding season.
View Article and Find Full Text PDFThe vocal recognition of newborn kids by their mother at 2 days postpartum and the possible existence of interindividual differences in the voice structure of newborn kids were investigated in two separate studies. The ability of goats to discriminate between the bleats of their own versus an alien kid was tested at 2 days postpartum in mothers being prevented access to visual and olfactory cues from the young. Goats spent significantly more time on the side of the enclosure from which their own kid was bleating, looked in its direction for longer, and responded more frequently to the bleats of their own than to those of the alien kid (p < 0.
View Article and Find Full Text PDFMother sheep and goats develop an early bond with their neonate on the basis of olfactory recognition. We investigated whether goats were also able to show early (<24 hr postpartum) nonolfactory discrimination of their kids, as already reported in sheep. In a first experiment, we found that goats are not able to recognize their kid at 1 m away on the basis of olfactory cues alone.
View Article and Find Full Text PDFIn postparturient goats, olfactory recognition of the young allows the establishment of a selective bond between the mother and her kids. Once this bond is formed, the mother rejects alien young that attempt to suckle. We tested whether the development of the maternal selective bond in goats modulates prolactin (PRL) and oxytocin (OT) release in response to suckling.
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