RESUMEN
Implementation of guidelines to reduce the amount of biodegradable municipal waste (BMW) sent to landfill has created a need in the waste-management industry to investigate possible methods of accelerating biostabilisation of residual BMW. The effect of commercially feasible manipulations (lime and green waste (GW)) on the rate of biostabilisation of the fine (<20 mm) fraction of residual BMW was investigated. The physical and chemical attributes of the composted wastes were measured, and their bacterial communities profiled using traditional culture-based methods. In addition, ammonia-oxidising microbes were monitored during the biostabilisation process using molecular profiling methods. Addition of GW accelerated biostabilisation, reduced conductivity and increased the levels of ammonia-oxidising bacterial (AOB) and archaeal (AOA) genes. The best stability was noted in the dual (Lime + GW) treatment, which was under the limit of 13 mmol O2 kg DM-1 h-1 recommended by the Irish compost standard. Biostabilised wastes met recommendations for source-segregated compost for pH (6-8) and pathogens (E. coli and Salmonella), but not heavy metals, indicating their unsuitability for uses other than landfill cover. Levels of AOA genes (log 3-6 g-1 DM) were higher than AOB (log 1-6 g-1 DM, indicating AOA may contribute more to potential ammonia oxidation in residual BMW composting.
Asunto(s)
Compostaje , Amoníaco , Archaea/genética , Compuestos de Calcio , Escherichia coli , Oxidación-Reducción , Óxidos , Microbiología del Suelo , Residuos SólidosRESUMEN
BACKGROUND: Linear type traits, which reflect the muscular characteristics of an animal, could provide insight into how, in some cases, morphologically very different animals can yield the same carcass weight. Such variability may contribute to differences in the overall value of the carcass since primal cuts vary greatly in price; such variability may also hinder successful genome-based association studies. Therefore, the objective of our study was to identify genomic regions that are associated with five muscularity linear type traits and to determine if these significant regions are common across five different breeds. Analyses were carried out using linear mixed models on imputed whole-genome sequence data in each of the five breeds, separately. Then, the results of the within-breed analyses were used to conduct an across-breed meta-analysis per trait. RESULTS: We identified many quantitative trait loci (QTL) that are located across the whole genome and associated with each trait in each breed. The only commonality among the breeds and traits was a large-effect pleiotropic QTL on BTA2 that contained the MSTN gene, which was associated with all traits in the Charolais and Limousin breeds. Other plausible candidate genes were identified for muscularity traits including PDE1A, PPP1R1C and multiple collagen and HOXD genes. In addition, associated (gene ontology) GO terms and KEGG pathways tended to differ between breeds and between traits especially in the numerically smaller populations of Angus, Hereford, and Simmental breeds. Most of the SNPs that were associated with any of the traits were intergenic or intronic SNPs located within regulatory regions of the genome. CONCLUSIONS: The commonality between the Charolais and Limousin breeds indicates that the genetic architecture of the muscularity traits may be similar in these breeds due to their similar origins. Conversely, there were vast differences in the QTL associated with muscularity in Angus, Hereford, and Simmental. Knowledge of these differences in genetic architecture between breeds is useful to develop accurate genomic prediction equations that can operate effectively across breeds. Overall, the associated QTL differed according to trait, which suggests that breeding for a morphologically different (e.g. longer and wider versus shorter and smaller) more efficient animal may become possible in the future.
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Bovinos/genética , Músculo Esquelético/química , Carne Roja/análisis , Animales , Cruzamiento , Bovinos/clasificación , Bovinos/crecimiento & desarrollo , Bovinos/fisiología , Femenino , Genómica , Modelos Lineales , Masculino , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Secuenciación Completa del GenomaRESUMEN
Severe prenatal undernutrition is usually associated with low birth weights in offspring and disorders including hypertension, obesity, and diabetes. Whether alterations in maternal nutrition insufficient to impair birth weight or prenatal growth impact the cardiovascular, stress, or metabolic systems is unknown. In addition, little is known about the effects of maternal dietary restriction on development of the reproductive system in mammals. Here, we use the bovine model, which has a gestational length and birth rate similar to humans, to show that offspring from nutritionally restricted dams (during the first trimester) were born with identical birth weights and had similar postnatal growth rates (to 95 wk of age), puberty, glucose metabolism, and responses to stress compared to offspring from control mothers. However, an increase in maternal testosterone concentrations was detected during dietary restriction, and these dams had offspring with a diminished ovarian reserve (as assessed by a reduction in antral follicle count, reduced concentrations of anti-Müllerian hormone, and increased follicle-stimulating hormone concentrations), enlarged aorta, and increased arterial blood pressure compared with controls. Our study links transient maternal undernutrition and enhanced maternal androgen production with a diminished ovarian reserve as well as potential suboptimal fertility, enlarged aortic trunk size, and enhanced blood pressure independent of alterations in birth weight, postnatal growth, or stress response and glucose tolerance. The implications are that relatively mild transient reductions in maternal nutrition during the first trimester of pregnancy (even those that do not affect gross development) should be avoided to ensure healthy development of reproductive and cardiovascular systems in offspring.
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Sistema Cardiovascular/fisiopatología , Desnutrición/veterinaria , Ovario/fisiopatología , Preñez , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Animales , Animales Recién Nacidos , Bovinos , Femenino , Retardo del Crecimiento Fetal/fisiopatología , Edad Gestacional , Desnutrición/complicaciones , Desnutrición/fisiopatología , Fenómenos Fisiologicos Nutricionales Maternos/fisiología , Embarazo , Maduración Sexual/fisiologíaRESUMEN
A voluntary control programme for Johne's disease, the Irish Johne's Control Programme (IJCP) has been implemented in Ireland since 2017. The objective of this observational study was to assess Irish beef and dairy farmers' Johne's disease knowledge, implemented management practices and IJCP opinions. A questionnaire open to dairy and beef farmers was distributed via social media and email. In total 126 responses were used for this study; these responses came from mostly young farmers (18-25 years old) and represent a small proportion of the total number of dairy and beef farmers in Ireland whose average age is 55.Most respondents claimed to know what Johne's disease was (73%; 92/126) and associated the disease to loss of body condition (68%; 78/114) and diarrhoea (59%; 67/114). Twenty-eight respondents (mostly dairy farmers; 22/28) reported positive cases in their premises. And 38% reported to implement management practices to prevent Johne's disease transmission within or into their herd (i.e. management of milk for calf consumption and isolation of Johne's test-positive or newly purchased stock; 47/124).Eighteen percent (22/125) of respondents were, at the time of questionnaire or previously, members of the IJCP. The main benefits reported by some of the participating farmers were identification of positive cases (29%; 4/14), and management of milk for calf consumption (21%; 3/14). While the main disadvantage was inaccurate testing methods (50%; 10/20). The main reasons reported for the lack of participation in the IJCP were not being aware of the programme (52%; 53/102) and not having a Johne's disease problem on the farm (48%; 49/102).In conclusion, this study suggests that while young farmers are aware of Johne's disease, their participation in the IJCP is limited and could benefit from further promotion. Studies representing the wider farming community in Ireland are warranted to gather non-biased input and contribute to Johne's disease control in Ireland.
RESUMEN
The oviduct provides the environment to support gamete maturation, fertilisation and early embryo development. As there is a high incidence of early embryonic death in lactating dairy cows, this study compared expression of IGF family members in the oviduct between lactating Holstein-Friesian dairy cows (n=16, 81±2.4 days in milk) and nulliparous heifers (n=16, age 1.6±0.07 years) at three stages of the oestrous cycle: A) newly selected dominant follicle in the luteal phase, B) follicular phase before the LH surge and C) pre-ovulatory phase after the LH surge. Expression of IGF1, IGF2, IGF binding protein 2 (IGFBP2), IGFBP3 and IGFBP6 mRNA was determined in the ampulla of the oviduct. Oviduct side (ipsilateral or contralateral) with respect to the dominant follicle did not affect gene expression. Expression of IGF1 and all three IGFBPs increased significantly between the luteal and the pre-ovulatory phases, with no further significant alteration post-LH surge. Concentrations of circulating IGF1 were higher in heifers than in cows, as was the mRNA expression of IGF1, IGFBP3 and IGFBP6. The pre-LH surge rise in IGFBP2 mRNA was only observed in heifers. IGF2 expression was not influenced by either age or stage of cycle. These three IGFBPs are generally considered to inhibit IGF action. These results indicate tight regulation of IGF bioavailability in the oviductal environment around oestrus, with pronounced differences between cows and heifers, which are likely to influence early embryonic development. Further studies are required to assess the implications for embryo survival.
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Bovinos/genética , Estro/genética , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/genética , Lactancia/fisiología , Oviductos/metabolismo , Somatomedinas/genética , Animales , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Bovinos/metabolismo , Bovinos/fisiología , Industria Lechera , Ciclo Estral/genética , Ciclo Estral/metabolismo , Estro/metabolismo , Estro/fisiología , Femenino , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Lactancia/genética , Lactancia/metabolismo , ARN Mensajero/metabolismo , Somatomedinas/metabolismoRESUMEN
The failure of cows to successfully establish pregnancy after insemination is an important limiting factor for the efficiency of dairy production systems. The physiological reasons for this are many and pertain to the post partum and early pregnancy periods. Cows that suffer severe negative energy balance after parturition are prone to diseases (including uterine infection) that are, in part, explained by reduced function of the immune system, having negative consequences for subsequent fertility. In high-producing dairy cows, the duration and intensity of oestrus is low as a consequence of low circulating oestradiol concentrations, and after insemination, high embryo mortality is the single biggest factor reducing calving rates. Embryo mortality occurs as consequences of poor oocyte quality (probably caused by the adverse metabolic environment) and by poor maternal uterine environment (probably caused by carry-over effects of uterine infection and low circulating progesterone concentrations). Immediate improvements in the fertility of lactating cows on many farms can be achieved by applying existing knowledge, but longer-term sustained improvement will require additional knowledge in many areas including the physiology of the tissues that contribute to reproduction.
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Bovinos/fisiología , Industria Lechera , Inseminación Artificial , Preñez/fisiología , Animales , Metabolismo Energético/fisiología , Estro/fisiología , Femenino , Fertilidad/fisiología , Periodo Posparto/fisiología , EmbarazoRESUMEN
Sexual dimorphism, the phenomenon whereby males and females of the same species are distinctive in some aspect of appearance or size, has previously been documented in cattle for traits such as growth rate and carcass merit using a quantitative genetics approach. No previous study in cattle has attempted to document sexual dimorphism at a genome level; therefore, the objective of the present study was to determine whether genomic regions associated with size and muscularity in cattle exhibited signs of sexual dimorphism. Analyses were undertaken on 10 linear-type traits that describe the muscular and skeletal characteristics of both males and females of five beef cattle breeds: 1,444 Angus (AA), 6,433 Charolais (CH), 1,129 Hereford, 8,745 Limousin (LM), and 1,698 Simmental. Genome-wide association analyses were undertaken using imputed whole-genome sequence data for each sex separately by breed. For each single-nucleotide polymorphism (SNP) that was segregating in both sexes, the difference between the allele substitution effect sizes for each sex, in each breed separately, was calculated. Suggestively (P ≤ 1 × 10-5) sexually dimorphic SNPs that were segregating in both males and females were detected for all traits in all breeds, although the location of these SNPs differed by both trait and breed. Significantly (P ≤ 1 × 10-8) dimorphic SNPs were detected in just three traits in the AA, seven traits in the CH, and three traits in the LM. The vast majority of all segregating autosomal SNPs (86% in AA to 94% in LM) had the same minor allele in both males and females. Differences (P ≤ 0.05) in allele frequencies between the sexes were observed for between 36% (LM) and 66% (AA) of the total autosomal SNPs that were segregating in both sexes. Dimorphic SNPs were located within a number of genes related to muscularity and/or size including the NAB1, COL5A2, and IWS1 genes on BTA2 that are located close to, and thought to be co-inherited with, the MSTN gene. Overall, sexual dimorphism exists in cattle at the genome level, but it is not consistent by either trait or breed.
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Estudio de Asociación del Genoma Completo , Caracteres Sexuales , Animales , Bovinos/genética , Femenino , Genoma , Estudio de Asociación del Genoma Completo/veterinaria , Genómica , Masculino , Fenotipo , Polimorfismo de Nucleótido SimpleRESUMEN
Meticulous culling decisions, coupled with careful breeding decisions, are fundamental to shifting a population distribution in the favorable direction and improving profit per cow. Nevertheless, there is a paucity of easy-to-use dynamic tools to aid in culling decisions in beef cattle. The motivation for the present study was to develop a monetary-based culling tool, here referred to as the Beef Female's Profit Potential (BFPP), to identify females for culling. The BFPP reflects the expected lifetime profitability of an individual female in a herd for the expected remainder of her lifetime; this profit included that of the beef female herself as well as her progeny. The BFPP index framework was composed of 4 subindexes reflecting the value of an animal: (1) as a nulliparae (this was voided if the cow had already calved), (2) for the remainder of her current parity, (3) summed across each of her expected remaining parities, and (4) when she is retained within the herd and not voluntarily culled. Each subindex was comprised of different components reflecting both genetic and non-genetic effects associated with each female. Transition matrices predicting the expected longevity of each female and their expected month of calving were also utilized in calculating the expected remaining lifetime profitability of each female. The BFPP index was validated on 21,102 beef cows as well as their harvested progeny from 875 herds by stratifying the cows, within herd, into 4 strata based on their BFPP. The mean of the within-herd correlation between the BFPP and the Irish national replacement (i.e., breeding) index was, on average, 0.45 indicating the shortcomings of the breeding index as a culling tool. Cows within the top BFPP stratum had a genetic expectation of accruing almost an additional 36 profit per calving, relative to cows within the worst stratum; when validated on the cow's own calving interval and survival performance as well as their progeny's carcass performance, the actual phenotypic value was estimated to be an additional 32 profit per calving. A proportion of this additional profit was due to the harvested progeny of the high BFPP cows having, on average, heavier, more conformed carcasses with less fat cover relative to their poor BFPP contemporaries. This BFPP framework is a useful and easy-to-use tool to aid in producer decision making on the choice of females to voluntarily cull but also on which replacement heifers to graduate into the mature herd.
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Industria Lechera , Longevidad , Animales , Bovinos , Femenino , Lactancia , Paridad , EmbarazoRESUMEN
Linear type traits describing the skeletal characteristics of an animal are moderately to strongly genetically correlated with a range of other performance traits in cattle including feed intake, reproduction traits and carcass merit; thus, type traits could also provide useful insights into the morphological differences among animals underpinning phenotypic differences in these complex traits. The objective of the present study was to identify genomic regions associated with five subjectively scored skeletal linear traits, to determine if these associated regions are common in multiple beef and dairy breeds, and also to determine if these regions overlap with those proposed elsewhere to be associated with correlated performance traits. Analyses were carried out using linear mixed models on imputed whole genome sequence data separately in 1,444 Angus, 1,129 Hereford, 6,433 Charolais, 8,745 Limousin, 1,698 Simmental, and 4,494 Holstein-Friesian cattle, all scored for the linear type traits. There was, on average, 18 months difference in age at assessment of the beef versus the dairy animals. While the majority of the identified quantitative trait loci (QTL), and thus genes, were both trait-specific and breed-specific, a large-effect pleiotropic QTL on BTA6 containing the NCAPG and LCORL genes was associated with all skeletal traits in the Limousin population and with wither height in the Angus. Other than that, little overlap existed in detected QTLs for the skeletal type traits in the other breeds. Only two QTLs overlapped the beef and dairy breeds; both QTLs were located on BTA5 and were associated with height in both the Angus and the Holstein-Friesian, despite the difference in age at assessment. Several detected QTLs in the present study overlapped with QTLs documented elsewhere that are associated with carcass traits, feed intake, and calving difficulty. While most breeding programs select for the macro-traits like carcass weight, carcass conformation, and feed intake, the higher degree of granularity with selection on the individual linear type traits in a multi-trait index underpinning the macro-level goal traits, presents an opportunity to help resolve genetic antagonisms among morphological traits in the pursuit of the animal with optimum performance metrics.
RESUMEN
A dispersive liquid-liquid microextraction (DLLME) method, combined with HPLC-UV detection, was developed for the extraction and preconcentration of δ-tocopherol from bovine milk. This method was used to study the effect of supplementing cow feed with the seaweed Ascophyllum nodosum on vitamin content in milk. The optimal experimental conditions were determined: 200⯵L of chloroform (extraction solvent), 1.0â¯mL of ethanol (dispersive solvent), 5â¯mL of water (aqueous phase). Under these optimal conditions the DLLME method provided linearity in the range 0.01⯵g/mL to 8⯵g/mL with R2 values of 0.998. Limit of detection (LOD) was 0.01⯵g/mL, while the enrichment factor was 89. Cow feed that was supplemented with Ascophyllum nodosum was shown to increase δ-tocopherol levels from 3.82⯵g/mL to 5.96⯵g/mL.
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Alimentación Animal , Suplementos Dietéticos , Microextracción en Fase Líquida/métodos , Leche/química , Algas Marinas , Tocoferoles/análisis , Animales , Bovinos , Cromatografía Líquida de Alta Presión , Límite de Detección , Modelos Lineales , Reproducibilidad de los Resultados , Proyectos de Investigación , Tocoferoles/química , Tocoferoles/aislamiento & purificaciónRESUMEN
Linear type traits describing the skeletal, muscular, and functional characteristics of an animal are routinely scored on live animals in both the dairy and beef cattle industries. Previous studies have demonstrated that genetic parameters for certain performance traits may differ between breeds; no study, however, has attempted to determine if differences exist in genetic parameters of linear type traits among breeds or sexes. Therefore, the objective of the present study was to determine if genetic covariance components for linear type traits differed among five contrasting cattle breeds, and to also investigate if these components differed by sex. A total of 18 linear type traits scored on 3,356 Angus (AA), 31,049 Charolais (CH), 3,004 Hereford (HE), 35,159 Limousin (LM), and 8,632 Simmental (SI) were used in the analysis. Data were analyzed using animal linear mixed models which included the fixed effects of sex of the animal (except in the investigation into the presence of sexual dimorphism), age at scoring, parity of the dam, and contemporary group of herd-date of scoring. Differences (P < 0.05) in heritability estimates, between at least two breeds, existed for 13 out of 18 linear type traits. Differences (P < 0.05) also existed between the pairwise within-breed genetic correlations among the linear type traits. Overall, the linear type traits in the continental breeds (i.e., CH, LM, SI) tended to have similar heritability estimates to each other as well as similar genetic correlations among the same pairwise traits, as did the traits in the British breeds (i.e., AA, HE). The correlation between a linear function of breeding values computed conditional on covariance parameters estimated from the CH breed with a linear function of breeding values computed conditional on covariance parameters estimated from the other breeds was estimated. Replacing the genetic covariance components estimated in the CH breed with those of the LM had least effect but the impact was considerable when the genetic covariance components of the AA were used. Genetic correlations between the same linear type traits in the two sexes were all close to unity (≥0.90) suggesting little advantage in considering these as separate traits for males and females. Results for the present study indicate the potential increase in accuracy of estimated breeding value prediction from considering, at least, the British breed traits separate to continental breed traits.