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1.
Trop Anim Health Prod ; 52(6): 2955-2967, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32535802

RESUMEN

Indigenous breeding practices of the farmers and the livestock production system form the bases for designing community-based breeding programs. The aim of this study was to characterize production system and examine breeding practices of the indigenous goat farmers in Hai district in Northern Tanzania to determine their relevance in establishing a community-based breeding program in the area. A cross-sectional survey was conducted in which information was collected from 160 households randomly selected from 6 villages. Average household herd was 29.2 goats with majority keeping less than 20 goats. Major reasons for keeping goats were income generation, meat and milk production. Controlled mating was practiced mainly using apron and castration. Castration was practiced using traditional methods to control breeding and improve meat quality. Farmers in the study area had large goat flocks and a small buck to doe ratio. Farmers do not have a good understanding of inbreeding and its negative effects but practise other good breeding methods which could impact the productivity of their animals. Diseases and feed shortages were the main constraints to production. Opportunities exist for a community-based breeding program to genetically improve goat productivity.


Asunto(s)
Crianza de Animales Domésticos , Cruzamiento , Cabras , Animales , Estudios Transversales , Femenino , Endogamia , Masculino , Tanzanía
2.
Animal ; 14(7): 1362-1370, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32100664

RESUMEN

Community-based breeding programs (CBBPs) for small ruminants have been suggested as alternatives to centralised, government-controlled breeding schemes which have been implemented in many developing countries. An innovative methodological framework on how to design, implement and sustain CBBPs was tested in three sites in Ethiopia: Bonga, Horro and Menz. In these CBBPs, the main selection trait identified through participatory approaches was 6-month weight in all three sites. In Horro and Bonga, where resources such as feed and water permitted larger litter sizes, twinning rate was included. Ten-year (2009 to 2018) performance data from the breeding programs were analysed using Average Information Restricted Maximum Likelihood method (AI-REML). Additionally, the socioeconomic impact of CBBPs was assessed. Results indicated that 6-month weight increased over the years in all breeds. In Bonga, the average increase was 0.21 ± 0.018 kg/year, followed by 0.18 ± 0.007 and 0.11 ± 0.003 kg/year in Horro and Menz, respectively. This was quite substantial in an on-farm situation. The birth weight of lambs did not improve over the years in Bonga and Horro sheep but significant increases occurred in Menz. Considering that there was no direct selection on birth weight in the community flock, the increased weights observed in Menz could be due to correlated responses, but this was not the case in Bonga and Horro. The genetic trend for prolificacy over the years in both Bonga and Horro flocks was positive and significant (P < 0.01). This increase in litter size, combined with the increased 6-month body weight, increased income by 20% and farm-level meat consumption from slaughter of one sheep per year to three. The results show that CBBPs are technically feasible, result in measurable genetic gains in performance traits and impact the livelihoods of farmers.


Asunto(s)
Cruzamiento , Ovinos , Animales , Peso Corporal , Etiopía , Femenino , Tamaño de la Camada/genética , Masculino , Fenotipo , Embarazo , Ovinos/genética , Factores Socioeconómicos
3.
Trop Anim Health Prod ; 52(4): 1933-1943, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31965413

RESUMEN

The absence of formal markets and the large variability of genetic groups and production systems of goats and sheep in developing countries hinder the implementation of traditional breeding programmes. Community-based breeding programmes (CBBP) for these species have been shown to be effective in these countries. In these programmes, the definition of the objectives and criteria of selection is done in a participatory way, which takes into account the desires and needs of the local farmers. We aimed to define the objectives and criteria of a CBBP for goats and sheep in the Inhamuns region, Ceará, Brazil, using a participatory rural appraisal (PRA). This methodology, which consist in an approach that aims to incorporate the knowledge and opinions of rural people in the planning and management of development projects and programmes, was performed in seven districts of two towns of the region (Tauá and Parambu). One hundred twenty-two farmer families participated in the survey. The PRA was able to provide important information, and its results showed that breeders of this region keep flocks of goats and sheep for social, economic and cultural benefits. In order of importance, the main objectives for goat farming were personal fulfilment (PERF), food source for family (FSF), income generation (INCG), savings (SAV) and cultural/family traditions (CULT), while for sheep farming were CULT, FSF, SAV, PERF and INCG. Disease resistance (RDI), adaptability (ADP), fertility (FERT), growth rate (GRA), host resistance of worms (HRW), body conformation (BC), temperament (TEM), longevity (LONG), body size (BSIZ), age at first kidding (AFK) and milk yield (MIY) were the main selection criteria that farmers use for goats. The most important selection criteria used for selecting sheep were ADP, RDI, HRW, GRA, FERT, LONG, BC, BS and age at first lambing. According to these objectives and criteria, the CBBP must consider the adaptation of the animals to the climate and management conditions of the region, the resistance to diseases and productive performance.


Asunto(s)
Cruzamiento/métodos , Participación de la Comunidad , Agricultores/psicología , Cabras , Oveja Doméstica , Adulto , Anciano , Anciano de 80 o más Años , Crianza de Animales Domésticos , Animales , Brasil , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
4.
Animal ; 13(2): 240-247, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29954467

RESUMEN

Genetic parameters and genetic trends for growth, reproduction, milk production and composition traits were estimated for Syrian (S) and Turkish (T) Awassi sheep and their crosses maintained at the International Center for Agricultural Research in the Dry Areas Tal Hadya station, Aleppo, Syria (now in Terbol station in Lebanon). The data were spread over 9 years. The individual breed additive effects of T were positive and significant (P0.05) for most growth traits. Crossing of T with S, however, resulted in desirable and significant (P<0.05) individual heterosis effects for all the reproduction, milk production and constituent yields. The heritability (h²) estimates, both direct and maternal, were low for BW, WW, WG and all reproductive traits indicating major influence of environmental factors, whereas milk yield and composition had medium values. Birth weight had moderate genetic correlation with WW and WG. The genetic correlation between WW and WG was high (0.724±0.951). Lambing interval had large negative genetic correlation with LWB and LWW. However, LI had medium significant correlations with all the milk production and composition traits. Larger litter weights at birth had high and negative influence on milk yield of the dam and its constituents. Genetic changes over years for all traits were non-significant. The lack of genetic change in the studied traits calls for systematic and organized selection scheme.


Asunto(s)
Leche/metabolismo , Reproducción/genética , Ovinos/genética , Animales , Cruzamiento , Femenino , Lactancia , Leche/química , Fenotipo , Ovinos/crecimiento & desarrollo , Ovinos/fisiología
5.
Trop Anim Health Prod ; 50(3): 643-650, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29177851

RESUMEN

We generated epidemiological information on the prevalence of nematode parasites and possible resistance/resilience of goats in three areas, Bati, Shinille, and Borana, of Ethiopia. A total of 350 breeding does were randomly selected and monitored for one year. Fecal egg counts (FEC), packed cell volume (PCV), body weight (BW), body condition score (BC), and fecal larvae identification were done. In Borana, the long rainy season had higher FEC, lower PCV, lower BC, and smaller BW compared to dry and short rainy seasons (p < 0.01). For Bati and Shinille, the differences between the seasons were significant (p < 0.01) but not clear-cut. Breed differences were also evident (p < 0.01) on FEC, PCV, and BW. The mean FEC for Borana goat was 158.5 ± 1.12, whereas for Bati it was 38.9 ± 1.12. Age differences did not have effect on FECs, PCV, and BC. No differences in parasite load, as reflected by FEC, was verified between male and female goats. In the wet season, large numbers of larvae were recovered from the study sites except for Bati. In the three sites, Haemonchus contortus followed by Trichostrongylus colubriformis were the dominant species. In the dry season, however, very little number of larvae was recovered, only of H. contortus in Bati and of H. contortus and T. colubriformis in Borana. Generally, the level of nematode infection was low. Therefore, nematode parasites are not a major problem and strategic control program using broad spectrum anthelmintic is not advisable. Rather, monitoring parasite load and selective de-worming should be sufficient to reduce productivity loses and pasture contamination.


Asunto(s)
Antihelmínticos/uso terapéutico , Heces/parasitología , Enfermedades de las Cabras/parasitología , Cabras/parasitología , Infecciones por Nematodos/veterinaria , Recuento de Huevos de Parásitos/veterinaria , Factores de Edad , Animales , Peso Corporal , Cruzamiento , Etiopía/epidemiología , Femenino , Geografía , Enfermedades de las Cabras/epidemiología , Haemonchus , Ganado/parasitología , Masculino , Parásitos , Lluvia , Estaciones del Año , Factores Sexuales , Especificidad de la Especie , Tiempo (Meteorología)
6.
Genet Mol Res ; 15(2)2016 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-27323203

RESUMEN

Polynomial functions of different orders were used to model random effects associated with weight of Santa Ines sheep from birth to 196 days. Fixed effects included in the models were contemporary groups, age of ewe at lambing, and fourth-order Legendre polynomials for age to represent the average growth curve. In the random part, functions of different orders were included to model variances associated with direct additive and maternal genetic effects and with permanent environmental effects of the animal and mother. Residual variance was fitted by a sixth-order ordinary polynomial for age. The higher the order of the functions, the better the model fit the data. According to the Akaike information criterion and likelihood ratio test, a continuous function of order, five, five, seven, and three for direct additive genetic, maternal genetic, animal permanent environmental, and maternal permanent environmental effects (k = 5573), respectively, was sufficient to model changes in (co)variances with age. However, a more parsimonious model of order three, three, five, and three (k = 3353) was suggested based on Schwarz's Bayesian information criterion for the same effects. Since it was a more flexible model, model k = 5573 provided inconsistent genetic parameter estimates when compared to the biologically expected result. Predicted breeding values obtained with models k = 3353 and k = 5573 differed, especially at young ages. Model k = 3353 adequately fit changes in variances and covariances with time, and may be used to describe changes in variances with age in the Santa Ines sheep studied.


Asunto(s)
Tamaño Corporal/genética , Variación Genética , Modelos Genéticos , Carácter Cuantitativo Heredable , Ovinos/genética , Animales , Interacción Gen-Ambiente , Ovinos/crecimiento & desarrollo
7.
Arq. bras. med. vet. zootec ; 67(3): 732-740, May-Jun/2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-753937

RESUMEN

The aim of this study was to compare the following four genetic groups of hair sheep: Santa Inês (SI), Morada Nova (MN), Brazilian Somali (BS), and the F1 1/2Dorper x 1/2Morada Nova crossbreed on traits related to growth and parasitic infection. Thirty-three male lambs of the same age and of simple birth, under the same pre-weaning management conditions were used in the experiment. After weaning the animals were housed in a completely randomized design in paddocks made of Panicum maximum cv. Tanzania. Along the course of the research, the performance of the four groups of sheep was observed to be negatively affected by gastrointestinal parasites, but there was a genotype effect to the average daily weight gain (ADWG), where the SI and F1 genotypes presented higher values. The effects of genotype, time and genotype x time interaction were significant in weight and corporal score (CS) measurements. The BS lambs had the highest CS values throughout the experiment despite not presenting greater weight gain when compared to the SI and F1 breeds. There were also significant effects of time and genotype x time interaction for packed cell volume (PCV) and FAMACHA© score (FAM) and only the time effect was significant in the total number of eggs per gram (EPG) and total plasma protein (TPP). The MN lambs showed higher PCV values and unlike the other groups, presented a FAMACHA© score below 3 and PCV above 23% even having a higher EPG tendency, especially in the initial phase, indicating a possible higher resilience to infection caused by gastrointestinal parasites.


O objetivo deste estudo foi comparar quatro grupos genéticos de ovinos: Santa Inês (SI), Somalis Brasileira (SB), Morada Nova (MN) e 1/2 Dorper - 1/2 Morada Nova (F1) quanto às características de crescimento e de infecção parasitária. Trinta e três cordeiros machos, de mesma idade, nascidos de parto simples e submetidos às mesmas condições de manejo pré-desmame foram utilizados no experimento. Após o desmame, os animais foram alojados em piquetes de capim Panicum maximum cv. Tanzânia, em um sistema rotativo de pastejo sob um delineamento inteiramente ao acaso. Os resultados mostraram que, ao longo do experimento, o desempenho ponderal dos quatro grupos genéticos foi negativamente afetado pela infecção por endoparasitas, mas o efeito de genótipo foi significativo para ganho de peso médio diário, e os grupos SI e F1 apresentaram melhores médias. O efeito do genótipo, tempo e interação genótipo x tempo foi significativo para o peso e o escore corporal. Os cordeiros da raça SB apresentaram maiores escores corporais ao longo do experimento, apesar do menor ganho de peso quando comparados aos dos grupos SI e F1. Houve efeito significativo do tempo e da interação genótipo x tempo para o hematócrito e para o grau FAMACHA©. Somente efeito do tempo foi verificado para as características OPG e proteína plasmática total. Os cordeiros da raça Morada Nova, ao contrário dos demais grupos, mantiveram o grau FAMACHA© inferior a 3 e hematócrito inferior a 23%, mesmo com tendência de maior OPG, principalmente na fase inicial, indicando uma possível maior capacidade de adaptação à infecção por endoparasitas.


Asunto(s)
Animales , Haemonchus/parasitología , Ovinos/crecimiento & desarrollo , Ovinos/parasitología , Strongyloides/parasitología , Trichostrongylus/parasitología , Recuento de Huevos de Parásitos/veterinaria , Pastizales/análisis , Pesos y Medidas Corporales/veterinaria
8.
Arq. bras. med. vet. zootec ; 65(4): 1208-1216, Aug. 2013. tab
Artículo en Inglés | LILACS | ID: lil-684481

RESUMEN

The aim of this study was to compare four genetic groups of sheep on the carcass and meat quality traits. Thirty-three contemporary and unrelated male lambs, all of single birth were used in the experiment, being thirteen from the Santa Inês (SI) breed, seven from the Brazilian Somali breed (BS), six from the Morada Nova (MN) breed and seven from the ½ Dorper - ½ Morada Nova (F1) crossbreed. The genotypes SI, BS and F1 presented similar performances in relation to hot and cold carcass weights, which values were 10.76±0.53kg and 10.46±0.52kg for SI, 9.20±0.73kg and 8.99±0.71kg for BS, and 9.35±0.73kg and 9.13±0.71kg for F1, respectively. The BS had a better hot carcass yield (47.10±0.88%) and cold carcass yield (46.00±0.87%). Better carcass conformation was observed in SI and F1 (2.73±0.12 and 2.50±0.17, respectively) while the BS presented a better finishing (3.29±0.20). The average for the rib eye area (REA) was 9.94±0.49cm², 8.66±0.67cm², 7.18±0.72cm² and 9.8±0.67cm², and for the carcass compactness index (CCI) it was 0.17±0.01kg/cm, 0.17±0.01kg/cm, 0.11±0.01kg/cm and 0.16±0,01kg/cm, for SI, SB, MN and F1, respectively. There were no significant differences between SI, BS and F1 regarding REA and CCI. Although, in general, the MN presented a relatively lower performance than the other genotypes, this breed had similar carcass yields and fat thickness when compared to SI and F1 and similar conformation and REA in comparison to the BS. Regarding meat quality, no differences were observed between genotypes, except for redness and cooking losses. It is concluded that no one group had a higher or lower performance in all traits analyzed. Moreover, for the management conditions employed in this study, there was evidence of greater specialization in meat production for genotypes SI, BS and F1 when compared to MN, although there are no substantial differences between the four groups regarding meat quality.


O objetivo deste estudo foi comparar quatro grupos genéticos de ovinos quanto às características de carcaça e de qualidade da carne. Trinta e três cordeiros, contemporâneos, nascidos de parto simples e sem relação de parentesco, foram utilizados no experimento, sendo 13 da raça Santa Inês (SI), sete da raça Somalis Brasileira (SB), seis da raça Morada Nova (MN) e sete ½ Dorper - ½ Morada Nova (F1). Os genótipos SI, SB e F1 apresentaram desempenhos similares quanto ao peso das carcaças quente e fria, cujos valores foram 10,76±0,53kg e 10,46±0,52kg para o SI, 9,20±0,73kg e 8,99±0,71kg para o SB, 9,35±0,73kg e 9,13±0,71kg para o F1, respectivamente. A raça SB apresentou melhor rendimento de carcaça quente (47,10 ±0,88%) e de carcaça fria (46,00±0,87%). Os genótipos SI e F1 apresentaram melhores conformações (2,73±0,12 e 2,50±0,17, respectivamente), enquanto o SB apresentou melhor acabamento (3,29±0,20). As médias para área de olho de lombo (AOL) foram 9,94±0,49cm², 8,66±0,67cm², 7,18±0,72cm² e 9,8±0,67cm² e para o índice de compacidade da carcaça (ICC) foram 0,17±0,01kg/cm, 0,17±0,01kg/cm, 0,11±0,01kg/cm e 0,16±0,01kg/cm, para SI, SB, MN e F1, respectivamente. Não houve diferença significativa entre os genótipos SI, SB e F1 quanto à AOL e ao ICC. Apesar de, no geral, a raça MN apresentar desempenho relativamente inferior aos demais genótipos quanto às características de carcaça analisadas, essa raça apresentou rendimentos de carcaça e espessura de gordura similar ao SI e F1 e conformação e AOL similar ao SB. Não houve um grupo superior ou inferior para todas as características analisadas. Por outro lado, para as condições de manejo empregadas neste estudo, evidenciou-se maior especialização para produção de carne dos genótipos SI, SB e F1 em relação ao grupo MN. Não houve diferenças importantes entre os diferentes genótipos quanto à qualidade da carne.


Asunto(s)
Animales , Calidad de los Alimentos , Genotipo , Carne , Ovinos
9.
Braz J Med Biol Res ; 43(3): 249-56, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20401432

RESUMEN

A series of studies have shown that the heavy burdens of diarrheal diseases in the first 2 formative years of life in children living in urban shanty towns have negative effects on physical and cognitive development lasting into later childhood. We have shown that APOE4 is relatively common in shanty town children living in Brazil (13.4%) and suggest that APOE4 has a protective role in cognitive development as well as weight-for-height in children with heavy burdens of diarrhea in early childhood (64/123; 52%), despite being a marker for cognitive decline with Alzheimer's and cardiovascular diseases later in life. APOE2 frequency was higher among children with heaviest diarrhea burdens during the first 2 years of life, as detected by PCR using the restriction fragment length polymorphism method, raising the possibility that ApoE-cholesterol balance might be critical for growth and cognitive development under the stress of heavy diarrhea burdens and when an enriched fat diet is insufficient. These findings provide a potential explanation for the survival advantage in evolution of genes, which might raise cholesterol levels during heavy stress of diarrhea burdens and malnutrition early in life.


Asunto(s)
Apolipoproteínas E/genética , Diarrea Infantil/genética , Polimorfismo Genético/genética , Apolipoproteínas E/metabolismo , Brasil , Desarrollo Infantil , Preescolar , Cognición , Estudios de Cohortes , Diarrea Infantil/complicaciones , Diarrea Infantil/metabolismo , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Lactante , Recién Nacido , Masculino , Mucosa Bucal/citología , Reacción en Cadena de la Polimerasa , Factores Socioeconómicos
10.
Braz. j. med. biol. res ; 43(3): 249-256, Mar. 2010. tab, graf
Artículo en Inglés | LILACS | ID: lil-539712

RESUMEN

A series of studies have shown that the heavy burdens of diarrheal diseases in the first 2 formative years of life in children living in urban shanty towns have negative effects on physical and cognitive development lasting into later childhood. We have shown that APOE4 is relatively common in shanty town children living in Brazil (13.4 percent) and suggest that APOE4 has a protective role in cognitive development as well as weight-for-height in children with heavy burdens of diarrhea in early childhood (64/123; 52 percent), despite being a marker for cognitive decline with Alzheimer’s and cardiovascular diseases later in life. APOE2 frequency was higher among children with heaviest diarrhea burdens during the first 2 years of life, as detected by PCR using the restriction fragment length polymorphism method, raising the possibility that ApoE-cholesterol balance might be critical for growth and cognitive development under the stress of heavy diarrhea burdens and when an enriched fat diet is insufficient. These findings provide a potential explanation for the survival advantage in evolution of genes, which might raise cholesterol levels during heavy stress of diarrhea burdens and malnutrition early in life.


Asunto(s)
Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Apolipoproteínas E/genética , Diarrea Infantil/genética , Polimorfismo Genético/genética , Apolipoproteínas E/metabolismo , Brasil , Desarrollo Infantil , Cognición , Estudios de Cohortes , Diarrea Infantil/complicaciones , Diarrea Infantil/metabolismo , Frecuencia de los Genes , Genotipo , Mucosa Bucal/citología , Reacción en Cadena de la Polimerasa , Factores Socioeconómicos
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