Producción de leche en vacas de doble propósito tratadas conoxitocina bajo condiciones de trópico húmedo mexicano

Research employing crossbred cows (½, ¾ and 7/8 B. Taurus x B. indicus) during the first 60 d of lactation was carried out at three commercial dairies, where feeding is based fundamentally on rotational grazing of tropical grasses. Supplemental feeding of the cows and their calves varied among the herds, but consisted mainly of mineral salts, poultry litter and other local resources. Two treatments related to the milking procedures were compared at each site. At Rancho Los Rejones (RLR) 11 cows per group were subjected to either: no stimulation to milk letdown other than that involved in routine 2x/d mechanical milking (control) or injection of 8 IU of oxytocin (OT) a.m. and p.m., three quarters being milked and the other left to be suckled by the calf. At Rancho Las Palmas (RLP) and Rancho La Isla (RLI) the 60-d period was divided into four successive 15-d phases. At RLP two groups of nine cow alternated by phase between the treatments: 8 IU/d of OT at the sole daily mechanical milking of three quarters or dummy insertion of a hypodermic needle without hormone (HN). At RLI one group of six cows received teat simulation by the calf (CS) prior to hand milking and six others received 10 IU/d of OT during two 15-d phases, alternating with CS in the other two phases. Milk production (kg/d) responded more to OT use than to routine stimulation at RLR (8.46 vs. 4.28, P<0.01), to HN at RLP (4.07 vs. 2.73, P<0.001) or to CS at RLI (8.58 vs. 5.48, P<0.05). At RLR body condition score of the cows did not differ between treatments, but at RLI use of OT resulted in greater weight loss than CS (51.08 vs. 17.24 kg). Weight gain of the calves (g/d) of cows treated with OT was slightly higher at RLR (381 vs. 328), but lower at RLP (252 vs. 333) and especially at RLI (561 vs. 719, P<0.01) relative to non-use of the exogenous hormone. In conclusion, the use of OT in early lactation improved milk yield, but it can also result in weight loss by the dam and reduced weight gain by the calf, to the detriment of double purpose operations.Se realizó experimentación usando vacas cruzas (½, ¾ and 7/8 B. taurus x B. indicus) durante los primeros 60-d de lactancia en tres ranchos comerciales donde la alimentación se basa fundamentalmente en pastoreo rotativo de gramíneas tropicales. La alimentación suplementaria de las vacas y sus crías varió entre los tres hatos, pero constó mayormente de sales minerales, pollinaza y otros recursos locales. Se compararon dos tratamientos relacionados con el ordeño en cada lugar. En Rancho Los Rejones (RLR) se sometieron 11 vacas por grupo a los tratamientos: ningún estímulo para la eyección de la leche en adición al rutinario del ordeño mecánico 2 x/d (control) o inyección de 8 UI de oxitocina (OT) a.m. y p.m., ordeñándose tres pezones y dejando el otro para la cría. En Rancho Las Palmas (RLP) y Rancho La Isla (RLI) se dividió al período de 60 d en cuatro sucesivos lapsos de 15. En RLP se alternaron por lapso dos grupos de nueve vacas entre los tratamientos: 8 UI/d de OT al ordeño mecánico único del día de tres pezones o la inserción de una aguja hipodérmica sin inyectar hormona (AH). En RLI un grupo de seis vacas recibió el estímulo de la cría sobre los pezones (EC) antes del ordeño manual y otras seis recibieron 10 UI/d de OT durante dos lapsos de 15 d, alternando con EC en los otros dos. La cosecha de leche (kg/D) respondió mejor al uso de OT que al estímulo rutinario en RLR (8.46 vs. 4.28, P<0.01), a AH en RLP (4.07 vs. 2.73, P<0.001) o a EC en RLI (8.58 vs. 5.48, P<0.05). En RLR la puntuación de condición corporal de las vacas no difirió entre tratamientos, pero en RLI el uso de OT resultó en mayor pérdida de peso materno que el EC (51.08 vs. 17.24 kg). La ganancia de peso de las crías (g/d) de vacas tratadas con OT fue levemente mayor en RLR (381 vs. 328), pero menor en RLP (252 vs. 333) y RLI 561 vs. 719, P<0.01) relativo al no uso de la hormona exógena. En conclusión, el uso de OT en lactación temprana promovió mayor producción de leche vendible, pero puede a la vez resultar en pérdida de peso corporal de la vaca y ganancias de peso menores en las crías, efecto adverso en un sistema doble propósito

Duración del ciclo estral y dinámica ovárica en vaquillas de doble propósito tratadas con oxitocina en el trópico

Se evaluó la aplicación de 20 UI/d de oxitocina (n=5) o agua salina (n=5) sobre el ciclo estral, dinámica ovárica y concentraciones de progesterona en vaquillas. El desarrollo folicular fue monitoreado por ultrasonido transrectal durante un ciclo estral. Las concentraciones de progesterona en la fase luteal intermedia fueron diferentes (P <0.08), con posibles efectos en la viabilidad embrionaria y el número de folículos en la primera y segunda onda folicular

Ictiofauna de la pesquería ribereña en Bahía de Navidad, Jalisco, México, asociada al evento El Niño 1997-1998

Se cuantificó la ictiofauna obtenida por la pesquería ribereña de Bahía de Navidad, Jalisco, México durante 1998. Se capturaron 6 944 ejemplares distribuidos en 130 especies (3 231 kg). Las familias con mayor número de especies fueron Carangidae, Haemulidae y Sciaenidae. Las especies más importantes en número y biomasa fueron Microlepidotus brevipinnins, Caranx caninus, C. caballus. El máximo número de especies se registró en junio (61), mínimo en marzo (33). En enero se capturó la mayor abundancia (1397 organismos), la menor durante agosto (25). La mayor biomasa fue en enero (556.5 kg), y la menor en agosto (114.7 kg). Dieciocho especies acumularon el 86.7 % de la abundancia total, mientras que 20 especies reúnen el 86.3 % de la biomasa. De igual forma, se encontraron grandes diferencias entre el número de especies, la abundancia y la biomasa capturados en los diferentes tipos de redesThe ichthyofauna fished in Bahía de Navidad. Jalisco, Mexico in the Central Pacific was surveyed during 1998. Six thousand nine hundred and fourty-four organisms of 130 species were caught which weighted P. 231 kg. Nearly 30 % of the species belonged to Carangidae, Haemulidae and Sciaenidae. The most important species in number and biomass were Microlepidotus brevipinnins, Caranx caninus and C. caballuso Species number, abundance and biomass fluctuated during the year. The largest number of species was caught in June (61), the minimum in March (33). January had the maximum abundance (1 397 organisms), while the minimum was obtained during August (251). The maximum biomass values were from January (556.5 kg), and the lowest from August (114.7 kg). Eighteen species accumulated 87 % of the total abundance. while 20 species represented 186.3 % of the biomass. There were large in differences species number, abundance and biomass nets of differ lent mesh siz

Déficits neurológicos y aracnoiditis secundarios a anestesia neuroaxial: rol de parestesias, punciones durales, anestésicos locales y género: Protocolo para su tratamiento

Introduction: Among the complications of neuroaxial anesthesia, arachnoiditis and neurological deficit represent one of the most serious problems that anesthesiologists can face. Although the real frequency of this complication is unknown, the functional consequences for the patient and legal repercussions for the physician are devastating, mainly because most patients are not treated in a timely fashion, increasing the probability of a catastrophic outcome. Methods: Case review. Results: We reviewed a series of cases and analyzed the factors that possibly influenced the presence of complications, the treatments used and their effectiveness in reducing permanent disability and in achieving recovery, as well as the results of their timely application. Discussion: Once these complications appear, the primary objective is to initiate a therapeutic plan that avoids or reduces permanent sequels. To do this, specific treatment that allows functional recovery must be started immediately. However, currently there is no treatment protocol with demonstrated effectiveness in reducing sequels.Introducción: De las complicaciones de la anestesia neuroaxial, la aracnoiditis y el déficit neurológico representan uno de los problemas más serios a los que pueda enfrentarse el anestesiólogo, aun cuando la frecuencia real es desconocida las consecuencias funcionales para los pacientes y legales para el médico son devastadoras, debido principalmente al hecho que la mayor parte de los pacientes no son tratados con oportunidad y las probabilidades de un desenlace catastrófico aumentan. Material y método: Revisión de casos. Resultados: Se presenta una serie de casos en los que se analizan los factores que posiblemente influyeron en la presencia de las complicaciones, los tratamientos empleados y su eficacia para disminuir la incapacidad remanente y lograr su recuperación, así como el resultado de aplicarlo oportunamente. Discusión: Es necesario reconocer que una vez que estas complicaciones se presentan, el objetivo principal es iniciar un plan terapéutico que evite o disminuya las secuelas permanentes, para lo cual se requiere iniciar inmediatamente un tratamiento específico que permita la pronta recuperación de la función; sin embargo, en la actualidad, aún no hay un protocolo de tratamiento que haya demostrado ser eficaz en la disminución de las secuelas

The fish species composition and variation of catch from the small-scale gillnet fishery before, during and after the 1997-1998 ENSO event, central Mexican Pacific

In the tropical and subtropical coastal zone, were highly diverse fish communities occur, it is important to study the small scale fisheries exploiting these communities. For this study, 219 fishing days were carried out in Bahia de Navidad, Jalisco, Mexico. Four gillnets with different mesh sizes (76.2, 88.9, 101.6 and 114.3 mm) were used for the fishing operations, from April 1994 to March 1995 and from January 1998 to December 2000. A total of 26126 organisms weighting 11680 kg were caught. One hundred and eighty three species belonging to 57 families and 19 orders were identified. Ten species accumulated more than 60% of the total abundance and biomass, the remaining species (173) individually contributed with less than 2% of the total abundance and biomass. The most important species in the catch were Microlepidotus brevipinnis, Caranx caballus, Haemulon flaviguttatum, Scomberomorus sierra, C. caninus, C. sexfasciatus, Lutjanus guttatus and L. argentiventris. The catch per unit of effort showed a large variation during the study, both in number and biomass. On average, 110 fishes and 48.5 kg fishing day-1 were caught. The maximum values were recorded during January and October 1998 (250 fishes and 100 kg fishing day-1), and the minimum values were recorded during September and November 1994 (25 org. and 10 kg fishing day-1). The total abundance and biomass was lower during the 1994-95 period (F=6.16, 8.32, P<0.05). There were statistically significant differences among the annual catch from each gillnet. All the environmental changes caused by the ENSO event had ecological and economic effects that can be rated from moderate to severe. Rev. Biol. Trop. 56 (1): 133-152. Epub 2008 March 31.<br>Se llevaron a cabo 219 días de pesca experimental en la Bahía de Navidad, Jalisco, México. Se utilizaron cuatro redes de enmalle de diferente luz de malla (76.2, 88.9, 101.6 and 114.3 mm de luz de malla), de abril de 1994 a marzo de 1995 y de enero de 1998 a diciembre de 2000. En total se capturaron 26126 organismos que pesaron 11680 kg. Fueron identificadas 183 especies pertenecientes a 57 familias y 19 órdenes. Diez especies acumularon más del 60% de la abundancia y biomasa total, el resto de las especies (173) individualmente aportaron menos del 2% de la abundancia y biomasa total. Las especies más importantes en la captura fueron Microlepidotus brevipinnis, Caranx caballus, Haemulon flaviguttatum, Scomberomorus sierra, C. caninus, C. sexfasciatus, Lutjanus guttatus y L. argentiventris. La captura por unidad de esfuerzo mostró una gran variación durante todo el periodo de estudio, tanto en número de organismos como en biomasa. En promedio se capturaron 110 organismos/día de pesca (48.5 kg/día de pesca). Los valores máximos se registraron durante enero y octubre de 1998 (250 peces y 100 kg por día de pesca), y el mínimo se registró durante septiembre y noviembre de 1994 (25 organismos y 10 kg por día de pesca). La abundancia y biomasa total fue menor durante el periodo 1994-1995 (F=6.16, 8.32, P<0.05). Se encontraron diferencias estadísticamente significativas entre la captura anual de las diferentes redes. Los cambios ambientales provocados por el evento ENOS tuvo efectos que pudieran considerarse de moderados a severos, tanto ecológicos como económicos

The first species composition and variation of cath from the small-gillnet fishery before, during and alter the 1997-198 ENSO event, in the central Mexican Pacific

In the tropical and subtropical coastal zone, were highly diverse fish communities occur, it is important to study the small scale fisheries exploiting these communities. For this study, 219 fishing days were carried out in Bahia de Navidad, Jalisco, Mexico. Four gillnets with different mesh sizes (76.2, 88.9, 101.6 and 114.3 mm) were used for the fishing operations, from April 1994 to March 1995 and from January 1998 to December 2000. A total of 26126 organisms weighting 11680 kg were caught. One hundred and eighty three species belonging to 57 families and 19 orders were identified. Ten species accumulated more than 60% of the total abundante and biomass, the remaining species (173) individually contributed with less than 2% of the total abundance and biomass. The most important species in the catch were Microlepidotus brevipinnis, Caranx caballus, Haemulon flaviguttatum, Scomberomorus sierra, C. caninus, C. sexfasciatus, Lutjanus guttatus and L. argentiventris. The catch per unit of effort showed a large variation during the study, both in number and biomass. On average, 110 fishes and 48.5 kg fishing day-1 were caught. The maximum values were recorded during January and October 1998 (250 fishes and 100 kg fishing day-1), and the minimum values were recorded during September and November 1994 (25 org. and 10 kg fishing day-1). The total abundance and biomass was lower during the 1994-95 period (F=6.16, 8.32, P&lt;0.05). There were statistically significant differences among the annual match from each gillnet. All the environmental changes caused by the ENSO event had ecological and economic effects that can be rated from moderate to sever

Productive response of hair ewes crossed with Damara and Dorper and growth of their lambs

ABSTRACT Profitability of sheep production depends on the reproductive response of ewes and growth of their lambs, which can be improved through the ram genotype. The aim of this study was to evaluate the reproductive response of Blackbelly (Bb), Pelibuey (Pb), Katahdin (Kat) and Dorper (Dor) ewes crossed with Damara (Dam) and Dor rams and the growth of their offspring. To measure percentage of single and multiple lambings (MLP), 234 Bb, Pb, Kat and Dor ewes were used. To measure lamb growth, the offspring of 86 Bb x Pb (BbPb) ewes and 73 Kat x Dor (KatDOR) ewes were used. Four Dor x BbPb, six Dam x BbPb and six Dam x KatDor lambs were slaughtered for carcass assessment. MLP was analyzed with the CATMOD procedure considering the factors age and breed. Lamb growth data were analyzed with the MIXED procedure, and those of carcass characteristics with the GLM procedure of SAS, using weight at slaughter as covariable. MLP was higher (P0.05) by effect of ram breed. It is concluded that Bb ewes are more prolific than Dor ewes; male lambs of Dam rams had post-weaning growth response and carcass yield similar to those of Dor rams, although the female lambs of Dor rams were heavier than those of Dam rams