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1.
Theriogenology ; 217: 143-150, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38277796

RESUMO

We tested whether utilising the male effect to stimulate ewes before the mating period can reduce the time to conception following the introduction of entire rams, and increase fertility, prolificacy, and reproductive rate (number of fetuses per 100 ewes exposed to fertile rams). A retrospective analysis was used to analyse records from 59,716 ewes collected over 34 years (1986-2020) from seven genotypes: Border Leicester, Composite (crossbred), Dorset, Merino, Dorset x Polypay, Rambouillet, White Suffolk. The dataset also included nulliparous young ewes (mated at age 8 months) and adult parous ewes. Vasectomized rams were used to stimulate 20,632 ewes before a mating period that lasted 2 or 3 estrous cycles, and the outcomes were compared with those from 39,084 ewes that had not been stimulated. Independently of genotype, utilising the male stimulus advanced the average conception date by 8 days for young ewes (P < 0.0001) and by 1 day for adult ewes (P < 0.0001). The male stimulus also increased the proportion of ewes that conceived in their first cycle by 33 % for young ewes and by 6 % for adult ewes (P < 0.0001). For the cycle of conception, there were significant (P < 0.0001) effects of two interactions: male stimulus x age at mating and male stimulus x live weight at mating. The male stimulus improved fertility in both adult ewes (99.8 % vs 89 %; P < 0.001) and young ewes (77.7 % vs 81.3 %; P < 0.001). The male stimulus increased the number of young ewes (41.9 % vs 11.1 %; P < 0.001) and adult ewes (16.6 % vs 2.7 %; P < 0.001) that conceived multiple fetuses in the first 17 days of the mating period. The reproductive rate was improved by the male stimulus in young ewes (129 % vs 135 %; P < 0.001) but not in adult ewes (120 % vs 122 %; P = 0.12). When all animals for all breeds were included in the analyses, there were improvements in fertility, prolificacy, and reproductive rate as age and live weight increased at mating (P < 0.0001). We conclude that, independently of genotype, utilising the male stimulus before the mating period reduces the time to conception and improves reproductive performance in both young and adult ewes.


Assuntos
Fertilidade , Reprodução , Ovinos/genética , Animais , Masculino , Feminino , Estudos Retrospectivos , Reprodução/genética , Fertilização , Carneiro Doméstico
2.
Biology (Basel) ; 11(7)2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-36101442

RESUMO

The last third of gestation is a period of high energy and protein demand for the dam to support fetal growth and the following onset of lactation. Methionine is an essential amino acid that contributes to protein formation, fetal development, and milk synthesis; thus, is likely to have positive effects on the weight and size of the newborn and, afterward, milk yield and milk composition, which may improve growth patterns of the progeny. To test these hypotheses, we used 60 pregnant multiparous Alpine goats with similar live weights and gestational ages (~Day 100 of pregnancy; Mean ± SD; 1410 ± 14 days old and 50.4 ± 6.6 kg) and were separated into two groups: control and supplemented with the delivery. Treatments were T-MET (n = 30; received 1% herbal methionine Optimethione® dry matter based on from Day 100 of the pregnancy to delivery) or T-CTL (n = 30; served as the control and did not receive methionine). The methionine powder provided individual supplementation and was adjusted every week as the live weight and dry matter intake changed. At birth, the weight, body mass index (BMI), birth type, and sex of the kids were determined. Subsequently, the progeny was weighed weekly up to weaning. Two weeks after parturition, the milk composition was recorded weekly, and the milk yield was recorded monthly. The maternal live weight at the start (Mean ± SEM; T-CTL: 50.5 ± 1.1 vs. T-MET: 50.3 ± 1.3 kg) and end (T-CTL: 54.2 ± 1.3 vs. T-MET: 52.8 ± 1.4 kg) of the experiment did not differ statistically among treatments (p > 0.05); however, daily live weight changes tended to differ between groups (T-CTL: 73 ± 10 vs. T-MET: 51 ± 7 g day−1; p = 0.06). The birth weight (T-CTL: 3.1 ± 0.1 vs. T-MET: 3.5 ± 0.1 kg; p < 0.001), daily live weight change (T-CTL: 121 ± 6 vs. T-MET: 141 ± 6 g day−1; p < 0.01), and weaning weight (T-CTL: 8.3 ± 0.2 vs. T-MET: 9.3 ± 0.3 kg; p < 0.01) differed between treatments. The BMI at birth (T-CTL: 0.28 ± 0.01 vs. T-MET: 0.3 ± 0.01 units kg m−2; p < 0.01) and at weaning (T-CTL: 0.85 ± 0.1 kg vs. T-MET: 1.00 ± 0.06 units kg m−2; p < 0.05) differed between treatments. Milk components (protein, fat, lactose, and solids non-fat) and milk yield were similar between treatments (p > 0.05). It is concluded that the inclusion of methionine in the maternal goat diet during the last third of gestation increases the birth and growth variables of the progeny but without significant influence on the milk yield and composition.

3.
Foods ; 10(12)2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34945662

RESUMO

BACKGROUND: According to Mexican growers of 'Jalapeño' peppers, its commercialization is the primary limitation. Thus, consumer knowledge is critical to develop added-value strategies. The objective of this study was to identify 'Jalapeño' quality attributes to determine consumer preferences and willingness to pay, based on socioeconomic characteristics. METHODS: A nationwide face-to-face survey was carried out using the discrete choice experiment method. The survey included 1200 consumers stratified by gender, age and region. RESULTS: Heterogeneity analysis using the probabilistic segmentation model revealed three types of consumers: A price-sensitive segment, non-demanding consumers without specific preferences and selective consumers with a preference shifted toward specific 'Jalapeño' characteristics. Thus, detail-oriented producers must compete through price strategies, based on the marketplace (markets on wheels, grocery stores, or supermarkets) and through some quality attributes preferred by selective consumers. Therefore, results suggest that farmers should grow the correct varieties with appropriate agronomic management to cope consumer preferences. CONCLUSIONS: This paper contributes to the growing body of the 'Jalapeño' literature by explicitly investigating consumer preferences and willingness to pay for them.

4.
Biology (Basel) ; 10(3)2021 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-33805782

RESUMO

We tested whether the milk yield capacity of mixed-breed goats on a Chihuahuan desert rangeland in northern Mexico during the dry season affects milk composition, body weight gain, and weaning weight of their progeny. Milk yield and composition, and progeny postnatal growth performance, were recorded weekly. One week after kidding, mixed-breed goats (a mixture of Criollo × dairy breeds; n = 40) were allotted into medium (MP) or low (LP) milk yielding groups (20 goats per group). Mean 105-d total milk yield for MP and LP goats was 45.2 ± 12.5 and 20.7 ± 5.2 L, respectively. Milk lactose (4.3 vs. 4.2%) and solids-non-fat (SNF; 8.2 vs. 8.0) differed (p < 0.05) between MP and LP goats; milk protein content tended to differ (p = 0.08) between MP and LP goats with no difference for milk fat content (p > 0.05). Maternal body weight was positively associated with milk yield, milk lactose, and SNF content (p < 0.05 to p < 0.001). Goats giving birth to males produce more milk than goats giving birth to females, but milk fat percentage was higher in goats bearing females (p < 0.001). Milk yield and composition throughout lactation did not influence body weight gain (47.8 vs. 48.7 g/day for kids from MP and LP goats) and weaning weight (6.7 vs. 6.7 kg from MP and LP goats) of the offspring (p > 0.05). Birth weight and weaning weight of the progeny were positively related to maternal body weight (p ≤ 0.05). The postnatal growth of the kids was reduced, extending the time to reach market weight. Nevertheless, non-supplemented mixed-breed goats reared on semi-arid rangeland of northern Mexico have the potential for moderate milk production. Therefore, due to the limited nutrients ingested by grazing goats during the dry season, a nutritional supplement is necessary to keep up milk production and adequate growth of kids.

5.
Sci Rep ; 11(1): 7214, 2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33785817

RESUMO

We tested whether periconceptional nutrition with cladodes from the cactus, Opuntia ficus-indica, with or without protein-enrichment, improved the metabolomic profile and reproductive outcomes of adult female sheep. Sixty Rambouillet ewes of similar body weight were randomly allocated among three nutritional treatments that were fed during the breeding period (34 days): Control (Control; n = 20), Opuntia (Opuntia; n = 20) and protein-enriched Opuntia (E-Opuntia; n = 20). There were no effects of treatment on body weight but assessment of urine samples indicated that, for 76 metabolites, the Control and Opuntia groups differed completely (P < 0.05), whereas there was overlap between the Control and E-Opuntia groups. It appears that, in Opuntia-fed and Control-fed sheep, different functional groups are activated leading to changes in the metabolism of glucose, tyrosine, methane, and glycerolipids. Fertility and reproductive rate tended to be higher in the Opuntia (70% and 95%) and E-Opuntia (90% and 110%) groups than in the Control (55% and 65%), and an orthogonal contrast revealed the difference between Control and Opuntia to be significant for both reproductive variables (P < 0.05). We conclude that nutritional supplementation with Opuntia cladodes, with or without protein enrichment, increased fertility rate and reproductive rate of female sheep, without any accompanying increases in body weight. Our observations suggest that the reproductive responses to Opuntia do not simply reflect a response to good nutrition, but might be caused by specific metabolites/metabolomic pathways, perhaps by an activation of the metabolism of glucose, methane, tyrosine and glycerolipids. There are few reports relating these metabolomic compounds with the metabolism of the sheep, let alone with reproductive efficiency. The novelty of these discoveries suggests that we need further research into the mechanisms through which nutrition affects the reproductive system.


Assuntos
Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Opuntia , Ovinos/fisiologia , Ração Animal/análise , Animais , Cruzamento , Suplementos Nutricionais/análise , Feminino , Fertilização , Masculino , Metaboloma , Estado Nutricional , Opuntia/química , Gravidez , Resultado da Gravidez
6.
Animals (Basel) ; 10(6)2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32517317

RESUMO

The present study tested whether feeding ewes during the last third of pregnancy with cladodes of Opuntia (untreated or protein-enriched), as an alternative to alfalfa hay, would improve milk yield as well as the pre- and post-natal growth of their lambs. Sixty mature Rambouillet ewes and their progeny were randomly allocated among three nutritional treatments: (i) Control, fed alfalfa; (ii) Opuntia, fed untreated cladodes; (iii) E-Opuntia, fed protein-enriched cladodes (pre-treated with urea and ammonium sulphate). Birth weight did not differ among treatments (p > 0.05) but Control ewes produced more milk than both groups of Opuntia-fed ewes (p < 0.05). However, milk yield was not related to the growth of the progeny (p > 0.05) because lambs from E-Opuntia-fed ewes grew faster (p < 0.01) and were heavier at weaning (p < 0.05) than lambs from the other two groups. We conclude that Opuntia (with or without protein enrichment) can be used as an alternative to alfalfa hay for feeding ewes during the last third of pregnancy and therefore reduce production costs under extensive conditions in arid and semiarid regions. Moreover, protein-enriched Opuntia appears to improve postnatal lamb growth.

7.
CienciaUAT ; 14(2): 104-116, ene.-jun. 2020. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1124387

RESUMO

Resumen La asignación de recursos públicos a la investigación agropecuaria es un factor de desarrollo para el sector agroalimentario del país, pero deben estar orientados eficientemente hacia la generación de productos tecnológicos que otorguen beneficios a la población. El objetivo de este trabajo fue evaluar el beneficio económico a nivel sistema de producción y sociedad, derivado de la inversión pública en investigación y desarrollo, del paquete tecnológico para la producción de frijol en zonas de temporal de la región norte centro de México. Para evaluar el impacto en los sistemas de producción, se aplicaron 42 encuestas a productores adoptantes del paquete tecnológico en municipios de Aguascalientes y San Luis Potosí; mientras que, para el impacto a nivel sociedad, se estimó el retorno económico que produjo la inversión pública utilizada en el proceso de generación y adopción de la tecnología en el periodo 2009a 2025. La medición se realizó a través del valor actual neto (VAN), la tasa interna de retorno (TIR) y la relación beneficio costo (R B/C). El costo de producción de los adoptantes fue mayor en 36.3 % comparado con la tecnología tradicional; en tanto que, el rendimiento aumentó en 102 % y el ingreso neto incrementó en 322.6 %. A nivel sociedad, la evaluación reveló un VAN de $ 10.9 millones, lo que representó 4.1 veces lo invertido en la generación de la tecnología. La R B/C fue de 5.1 y la TIR fue mayor a la tasa media real de rendimiento considerada (9.5 %). El desarrollo y transferencia del paquete tecnológico para la siembra de frijol representó una buena inversión de recursos públicos, beneficiando a la población y a los productores, porque incrementa la producción alimentaria y el ingreso neto del agricultor.


Abstract The allocation of public resources to agricultural research is a factor of development for the agri-food sector of the country and should be efficiently oriented towards the generation of technological products that provide benefits to the population. The aim of this work was to evaluate the economic benefit at a level of production system and society, derived from public investment in research and development of the technological package for dry bean crop production in rainfed areas in north central Mexico. To evaluate the impact on the production systems, 42 questionnaires were administered to users of the technological package in municipalities of Aguascalientes and San Luis Potosí. Likewise, in order to assess the impact at a society level, the economic return produced by the public investment used in the generation and adoption process of technology in the 2009 to 2025 period was estimated. The evaluation was performed through the net present value (NPV), the internal rate of return (IRR) and the cost benefit ratio (B/C R). The production cost for adopters was 36.3 % higher compared to traditional technology; however, the yield increased by 102 % and the net income increased by 3226 %. At a society level, the evaluation revealed an NPV of $ 10.9 million, which represented 4.1 times more than what was invested in the generation of technology; the B/C R was 5.1 and the IRR was higher than the real average rate of return considered (9.5 %). The development and transfer of the technological package for sowing beans represented a good investment of public resources, benefiting the population and producers, because it increases food production and farmers' net income.

8.
Animals (Basel) ; 9(5)2019 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-31058831

RESUMO

Two experiments (Australia and Mexico) tested whether feed intake (FI) and wool production (WP) are affected by pregnancy (PRG), litter size (LZ), or lamb sex (LS) in Merino-type ewes. In Experiment-1, ewes were either not pregnant (NPR; n = 6), or carrying 1 (PR1; n = 7) or 3 (PR3; n = 11) fetuses, were studied in individual pens. NPR ewes had lower (p < 0.02) FI throughout PRG and lactation (LAC), except around lambing (p < 0.001). Following lambing, FI increased in PRG ewes (p < 0.001) to double the values in NPR ewes. PRG reduced WP (p < 0.001); in PR3, WP was lower than for both PR1 and NPR (p < 0.001). WP decreased during LAC and was lower in ewes rearing lambs than in NPR ewes (p < 0.001). Experiment-2 used 48 pregnant ewes (28 bearing singles and 20 bearing twins). Dam and lamb live weights (LW) and body condition (BC) were recorded from birth to weaning at 60 d, and dam fleece weight (DFW) was measured at weaning (12 months growth). WP was higher in ewes bearing and rearing single lambs than in ewes bearing twins (p < 0.001). DFW was positively (p < 0.01) related to LZ, dam LW, and BC, but not to changes in dam LW during LAC, or to lamb weight at birth or weaning, or LW gain, or LS. In conclusion, FI was affected during PRG and by LZ during LAC, whereas WP was influenced by LZ, but not LS, only during pregnancy.

9.
Rev. MVZ Córdoba ; 23(1): 6448-6460, Jan.-Apr. 2018. tab
Artigo em Inglês | LILACS | ID: biblio-957344

RESUMO

ABSTRACT Objective. The present study consisted in characterizing the dual-purpose cattle system and the factors that limit the productivity of this system in northern Sinaloa, Mexico. Material and Methods. We applied a survey to 214 producers and we analyzed the data with analyses of factors and conglomerate. Results. The analysis of factors identified five components: resources level, productivity, technological level, livestock management and socioeconomic aspects and these components explain 70.5% of the total cumulative variance. The conglomerate analysis identified three clusters: cluster 1 (52.5%, 105 producers) defined as a system focused on milk production. Cluster 2 (41.5%, 83 producers) defined as traditional farms of meat and milk production and Cluster 3 (6%; 12 producers) defined as farms focused on meat production. The three clusters present similar livestock management (p>0.05). The producers base their feeding strategies on grazing rangeland with seasonal supplementation of silage and commercial concentrate; however, each cluster differed (p<0.05) in the level of use of these resources. Conclusion. The present study identifies, in the dual-purpose cattle system in northern Sinaloa, low milk yield and limit forage resources as main problems that results in multiple strategies that the producers follow to solve it. The social aspects and the level of resources (land, animals, machinery and equipment and infrastructure) play an important role therefore they must be considered independently to help to define differentiated technological strategies.


RESUMEN Objetivo. El estudio consistió en realizar una caracterización del sistema bovinos de doble propósito y los factores que limitan la productividad de este sistema en el norte de Sinaloa, México. Materiales y Métodos. Se aplicó una encuesta a 214 productores y la información se analizó mediante un análisis de factores y de conglomerados. Resultados. El análisis de factores identificó cinco componentes; nivel de recursos, productividad, nivel tecnológico, manejo del ganado y aspectos socioeconómicos. Estos cinco factores explican el 70.5% del total de la varianza acumulada. El análisis de conglomerados identificó tres clústers o grupos: Clúster 1 (105 productores, 52.5%) se definió como sistema enfocado a la producción de leche, Clúster 2 (83 productores, 41.5%) definido como explotaciones tradicionales productoras de carne y leche y Clúster 3 (12 productores, 6%) definido como explotaciones enfocadas la producción de carne. Los tres clústers presentan un manejo similar del ganado (p>0.05). Los productores de los clústers basan sus estrategias de alimentación del ganado en el pastoreo con suplementación estacional de ensilaje y concentrado comercial, no obstante, cada clúster tiene diferentes (p<0.05) niveles de uso de recursos. Conclusiones. El presente estudio identifico, en los sistemas bovino de doble propósito del norte de Sinaloa, como problemas principales una baja producción de leche y escasez de forraje que se manifiesta en múltiples estrategias que siguen los productores para resolverla. Los aspectos sociales y el nivel de recursos (tierra, animales, maquinaria, equipo e infraestructura) juegan un papel importante por lo que deben de ser considerados de manera independiente para la definición de estrategias tecnológicas diferenciadas.


Assuntos
Bovinos
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