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1.
J Dairy Sci ; 106(6): 3918-3931, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37105873

RESUMO

Insufficient dry matter intake (DMI) of pasture by dairy cattle is a major factor limiting growth and milk production; however, it has been hypothesized that some dairy breeds may be more efficient grazers than others. This study was conducted to determine whether dairy breed types differ in DMI and feed efficiency when grazing either grass monoculture or grass-legume mixed pastures. The experiment compared 4 different dairy breed types (Jersey, Holstein, Holstein-Jersey crossbreds, and Montbéliarde-Swedish Red-Holstein 3-breed crossbreds) and 2 levels of pasture type [grass monoculture (MONO) and grass-birdsfoot trefoil (BFT) mixture (MX)] for a total of 8 treatments. Pastures were rotationally stocked with groups of 4 prepubertal heifers for 105 d for 3 yr, and DMI was determined from herbage disappearance. Feed conversion efficiency (FCE) and residual feed intake (RFI) were then derived from DMI, and heifer body weights (BW) and normalized to animal units (AU) as 40% metabolic mature BW of the corresponding dairy breed type to account for inherent differences in size and growth rates. We observed differences in DMI and feed efficiency among breed types and between pasture types. On average, Holsteins had the greatest overall DMI (4.4 kg/AU), followed by intermediate DMI by the crossbreds (4.0 kg/AU), and Jerseys had the least DMI (3.6 kg/AU). Heifers grazing MX pastures had on average 22% greater DMI than those grazing MONO, but heifers on grass monocultures were more efficient in converting DMI to BW gain (i.e., RFI/AU of 0.27 and -0.27, respectively; more negative RFI numbers indicate less DMI to achieve the expected gains). Overall, Jerseys had the most favorable feed efficiency; however, ranking of Holsteins and crossbreds depended upon the feed efficiency metric. This study is one of the first to compare the interaction of dairy breed and pasture quality on grazing efficiency. However, the lack of a breed type × pasture type interaction for DMI, FCE, or RFI indicated that none of these dairy breed types were better adapted than another breed type to pastures with contrasting levels of nutritive value.


Assuntos
Lotus , Bovinos , Animais , Feminino , Poaceae , Melhoramento Vegetal , Ingestão de Alimentos , Peso Corporal , Ração Animal/análise , Dieta/veterinária , Lactação
2.
PLoS Pathog ; 17(11): e1009952, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34767598

RESUMO

The breadth of animal hosts that are susceptible to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and may serve as reservoirs for continued viral transmission are not known entirely. In August 2020, an outbreak of SARS-CoV-2 occurred on five mink farms in Utah and was associated with high mink mortality (35-55% of adult mink) and rapid viral transmission between animals. The premise and clinical disease information, pathology, molecular characterization, and tissue distribution of virus within infected mink during the early phase of the outbreak are provided. Infection spread rapidly between independently housed animals and farms, and caused severe respiratory disease and death. Disease indicators were most notably sudden death, anorexia, and increased respiratory effort. Gross pathology examination revealed severe pulmonary congestion and edema. Microscopically there was pulmonary edema with moderate vasculitis, perivasculitis, and fibrinous interstitial pneumonia. Reverse transcriptase polymerase chain reaction (RT-PCR) of tissues collected at necropsy demonstrated the presence of SARS-CoV-2 viral RNA in multiple organs including nasal turbinates, lung, tracheobronchial lymph node, epithelial surfaces, and others. Localization of viral RNA by in situ hybridization revealed a more localized infection, particularly of the upper respiratory tract. Whole genome sequencing from multiple mink was consistent with published SARS-CoV-2 genomes with few polymorphisms. The Utah mink SARS-CoV-2 strains fell into Clade GH, which is unique among mink and other animal strains sequenced to date. While sharing the N501T mutation which is common in mink, the Utah strains did not share other spike RBD mutations Y453F and F486L found in nearly all mink from the United States. Mink in the outbreak reported herein had high levels of SARS-CoV-2 in the upper respiratory tract associated with symptomatic respiratory disease and death.


Assuntos
COVID-19/veterinária , Vison/virologia , Animais , COVID-19/epidemiologia , COVID-19/mortalidade , COVID-19/patologia , Surtos de Doenças/veterinária , Fazendas , Feminino , Pulmão/patologia , Masculino , RNA Viral/sangue , Reação em Cadeia da Polimerase em Tempo Real/veterinária , SARS-CoV-2/classificação , Utah/epidemiologia
3.
J Dairy Sci ; 104(10): 10863-10878, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34389144

RESUMO

Dairy heifers developed in certified organic programs, especially those utilizing pasture-based management schemes, have lower rates of gain than heifers raised in nonorganic confinement production systems in temperate climates, such as in the Intermountain West region of the United States. This study investigates the effects that different forages in a rotational grazing system have on development of organically raised Jersey heifers. Over 3 years, 210 yearling Jersey heifers were randomly assigned to one of 9 treatments, including a conventional confinement control where animals were fed a total mixed ration or one of 8 pasture treatments: Cache Meadow bromegrass (Bromus riparius Rehmann), QuickDraw orchard grass (Dactylis glomerata L.), Amazon perennial ryegrass (Lolium perenne L.), or Fawn tall fescue (Schendonorus arundinaceus [Schreb.] Dumort) and each individual grass interseeded with birdsfoot trefoil (Lotus corniculatus L., BFT). Each treatment had 3 blocks/yr over the 3-yr period, with each block having a 0.4 ha pasture of each treatment. Every 35 d, over a 105-d period, heifers were weighed and measured for hip height, and blood samples were collected to determine serum insulin-like growth factor-1 and blood urea nitrogen concentrations. Fecal egg counts were also assessed. Heifer body weight (BW), blood urea nitrogen, and insulin-like growth factor-1 concentrations were affected by treatment when analyzed over time. Heifers on grass-BFT pastures had increased BW compared with heifers on monoculture grass pastures. Heifers receiving a total mixed ration or perennial ryegrass+BFT had increased BW gain over the 105-d period compared with heifers grazing tall fescue+BFT, orchard grass, perennial ryegrass, meadow bromegrass, or tall fescue. Individually for all grass species, heifers grazing +BFT pastures had greater ending BW and weight gain than heifers grazing the respective grass monocultures. Furthermore, weight gain for heifers on perennial ryegrass+BFT, meadow bromegrass+BFT, and orchard grass+BFT were not different from those on a total mixed ration. Heifers grazing grass-BFT pastures had increased blood urea nitrogen compared with heifers grazing monoculture grass pastures. Heifer hip height and fecal egg counts were not affected by treatment. These results show that the addition of BFT to organic pasture improves growth of grazing replacement heifers. Economic analyses also demonstrate that interseeding grass pastures with BFT results in an increased economic return compared with grazing monoculture grass pastures. Grass pastures interseeded with BFT may be a sustainable option to achieve adequate growth of Jersey heifers raised in an organic pasture scenario in a temperate climate.


Assuntos
Festuca , Lotus , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Aumento de Peso
4.
Animals (Basel) ; 11(8)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34438817

RESUMO

Alternatives to routine antibiotic treatment of dairy cattle during the dry period before their next calving are of interest. This was a preliminary study of whether intramammary infusion of casein hydrolysate, administered alone or combined with standard dry treatment, accelerated the rate of mammary involution early in the dry period. Four treatments were studied in a split udder design. One udder half was assigned a treatment, and the contralateral half was administered dry cow treatment + internal teat sealant as a control. Treatments were casein hydrolysate, casein hydrolysate + dry cow treatment, casein hydrolysate + teat sealant and casein hydrolysate + dry cow treatment + teat sealant. Cows (n = 16) were blocked by a number of intramammary infections per udder half (0 or 1+) and randomized to treatments. Milk production was not different between control or treated udder halves post-calving. A generalized linear mixed model tested for differences between the treatment groups in the concentration of mammary involution indicators in milk: somatic cell count, bovine lactoferrin and bovine serum albumin. At 7 days, dry udder halves treated with casein hydrolysate had higher milk concentrations of lactoferrin than those treated with casein hydrolysate + dry cow treatment, casein hydrolysate + teat sealant and control. At 10 days dry, bovine serum albumin was higher in udder halves treated with casein hydrolysate than in those treated with casein hydrolysate + dry cow treatment, casein hydrolysate + dry cow treatment + teat sealant and control. Post-calving, casein hydrolysate-treated udder halves produced 51% of total milk, unchanged from before dry-off. There were seven total intramammary infections entering the dry period, all caused by coagulase-negative staphylococci. Cure rates (3/7, 43%) were not different among all treatments and control, partly because of the small sample size. Intramammary infusion of casein hydrolysate at the end of lactation may be an alternative or possible adjunct to antibiotic dry cow therapy.

5.
J Dairy Sci ; 104(10): 10879-10895, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33934863

RESUMO

Low dietary energy and decreased intake of herbage have been attributed to the reduced performance of grazing dairy cattle. We hypothesized that grasses with inherently greater energy would interact in a complementary way with condensed tannins (CT) in birdsfoot trefoil to increase herbage intake by grazing dairy heifers. Eight pasture treatments comprising high-sugar perennial ryegrass (Lolium perenne L.), orchardgrass (Dactylis glomerata L.), meadow bromegrass (Bromus riparius Rehmann), and tall fescue [Schendonorus arundinaceus (Schreb.) Dumort] were established in Lewiston, Utah as monocultures and binary mixtures with birdsfoot trefoil (Lotus corniculatus L.; BFT). Pasture treatments were rotationally stocked by Jersey heifers for 105 d in 2017 and 2018, and herbage samples were collected pre- and postgrazing for each 7-d grazing period and analyzed for herbage mass, nutritive value, and apparent herbage intake. We observed differences among pasture treatments in herbage quantity and nutritive value, as well as differences in herbage intake by grazing Jersey heifers. On average, grass-BFT mixtures had greater herbage intake than grass monocultures, and every grass-BFT treatment individually had greater herbage intake than their respective grass monocultures. Using multivariate analyses, we determined that approximately 50% of the variation in herbage intake was due to nutritive and physical herbage characteristics, with the most explanatory being characteristics related to fiber and energy, followed by those related to the percent of BFT in the herbage. Grass monocultures exhibited a range of inherent dietary energy, but there was indication that an imbalance of energy to crude protein (e.g., protein deficient) reduced intake of grass monocultures. Moreover, there was some evidence of a complementary effect between increased dietary energy and CT; however, low CT levels made it impossible to determine the effect of CT on herbage intake per se. This study confirmed that chemical and physical characteristics inherent to different pasture species have a large effect on herbage intake by grazing cattle. Pastures planted to binary mixtures of nutritious grasses and birdsfoot trefoil increase herbage intake of temperate pastures by grazing Jersey heifers.


Assuntos
Lolium , Lotus , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Poaceae , Estações do Ano
6.
Animals (Basel) ; 10(12)2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33333939

RESUMO

Humans have shaped carnivore behavior since at least the Middle Paleolithic period, about 42,000 years ago. In more recent times, spotted hyenas (Crocuta crocuta) in Ethiopia have adapted to living in urban areas, while humans have adapted to living with hyenas. Yet, relationships between coexisting humans and carnivores are rarely addressed beyond mitigating conflicts. We provided a case study for how to broadly think about coexistence and how to study it when measuring if humans and carnivores affect one another. We collected data in four Ethiopian cities: Mekelle, Harar, Addis Ababa, and Arba Minch. We held focus groups and key informant interviews that incorporated feedback from 163 people, representing a wide array of religious, economic, and educational backgrounds. We also determined how many hyenas resided in these cities, hyena behavioral responses to humans using a flight initiation test, and problem-solving abilities via puzzle box trials. We found that in three of the cities, hyenas and humans coexist at high densities and frequently encounter each other. While all participants recognized the importance of hyenas as scavengers to maintain a clean environment, there was pronounced variation in cultural perspectives across cities. For example, while the people of Harar revere hyenas in spiritual terms, in Arba Minch hyenas were regarded as nuisance animals. Hyenas were universally respected as a formidable predator across cities but reports of attacks on livestock and humans were few. Flight initiation tests revealed hyenas fled at significantly closer distances in Harar and Addis Ababa than in Mekelle. Hyenas succeeded at solving a puzzle box in Harar but not in Mekelle. These variable behavior in hyenas correlated to different human perceptions. Our case study results suggest that the hyena-human dynamic is highly variable across these locations. We conclude by exploring the implications of these findings for how humans and hyenas can shape one another's behavior. Developing studies to link human perceptions and animal behavior could advance wildlife conservation, especially in urban areas.

7.
Toxicon ; 167: 60-66, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31173794

RESUMO

Wild parsnip (Pastinaca sativa) has been associated with livestock and human photosensitization. An investigation of a natural occurrence of photosensitization of grazing horses identified wild parsnip as a possible cause. HPLC-MS and MS/MS analysis of this plant identified five furanocoumarins i.e., xanthotoxin, bergapten, isopimpinellin, imperatorin and a putative methoxyimperatorin. Goats fed this wild parsnip were largely unaffected. Xanthotoxin was not detected in the serum of parsnip-fed goats or in the serum of goats dosed orally or intravenous with purified xanthotoxin. Cutaneous application produced severe photodermatitis in goats and a horse consistent with topical exposure as the likely route to produce wild parsnip-induced photosensitivity. Wild parsnip-induced superficial necrotizing dermatitis was consistent with photodermatitis with no evidence of other allergic or inflammatory components.


Assuntos
Dermatite Fotoalérgica/veterinária , Furocumarinas/toxicidade , Pastinaca/toxicidade , Transtornos de Fotossensibilidade/veterinária , Fármacos Fotossensibilizantes/toxicidade , Animais , Furocumarinas/química , Furocumarinas/isolamento & purificação , Doenças das Cabras/induzido quimicamente , Cabras , Doenças dos Cavalos/induzido quimicamente , Cavalos , Transtornos de Fotossensibilidade/induzido quimicamente
8.
Immunogenetics ; 71(1): 35-47, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30269158

RESUMO

A decrease in the incidence of bovine mastitis, the costliest disease in the dairy industry, can be facilitated through genetic marker-assisted selective breeding programs. Identification of genomic variants associated with mastitis resistance is an ongoing endeavor for which genome-wide association studies (GWAS) using high-density arrays provide a valuable tool. We identified single nucleotide polymorphisms (SNPs) in Holstein dairy cattle associated with mastitis resistance in a GWAS by using a high-density SNP array. Mastitis-resistant (15) and mastitis-susceptible (28) phenotypic extremes were identified from 224 lactating dairy cows on commercial dairy farm located in Utah based on multiple criteria of mastitis resistance over an 8-month period. Twenty-seven quantitative trait loci (QTLs) for mastitis resistance were identified based on 117 SNPs suggestive of genome-wide significance for mastitis resistance (p ≤ 1 × 10-4), including 10 novel QTLs. Seventeen QTLs overlapped previously reported QTLs of traits relevant to mastitis, including four QTLs for teat length. One QTL includes the RAS guanyl-releasing protein 1 gene (RASGRP1), a candidate gene for mastitis resistance. This GWAS identifies 117 candidate SNPs and 27 QTLs for mastitis resistance using a selective genotyping approach, including 10 novel QTLs. Based on overlap with previously identified QTLs, teat length appears to be an important trait in mastitis resistance. RASGRP1, overlapped by one QTL, is a candidate gene for mastitis resistance.


Assuntos
Estudo de Associação Genômica Ampla , Técnicas de Genotipagem , Mastite Bovina/genética , ras-GRF1/genética , Animais , Bovinos , Feminino , Fenótipo , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas
9.
J Agromedicine ; 24(1): 35-45, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30362924

RESUMO

OBJECTIVES: Practicing veterinarians are exposed to unique occupational hazards and zoonotic diseases. National studies have highlighted an increase risk to injuries and a lack of veterinary awareness for these hazards. In Utah (and likely other states), reports of acquired zoonoses are sporadic, and underlying risk factors poorly understood. To better clarify occupational risk factors, the knowledge, attitudes, and behaviors of Utah veterinarians were examined. METHODS: A total sample of 809 Utah veterinarians were identified from the 2017 licensure listing provided by the Utah Division of Professional Licensing. These individuals were invited to participate in an internet-based survey to self-report musculoskeletal injuries associated with large animal palpation practices. The relationships between some variables and Precaution awareness (PA) score rankings were examined using logistic regression and odds ratios. RESULTS: Of 809 veterinarians, 223 (28%) responded, with 209 self-identifying as clinical veterinarians. Frequent palpation of large animals (equine or bovine) was performed by 43 (22%) of 197 responding veterinarians. Joint pain or injury was experienced by 29 (67%) of 43 responding veterinarians who frequently palpated large animals (equine or bovine). Animal bites, needle-sticks, and cuts were the most frequently reported injuries within the past year. There were 44 (22%) of 197 respondents who reported having contracted a zoonotic disease. Most of the respondents failed to use appropriate PPE when examining an ill animal or when handling potentially infectious specimens. Clinical veterinarians who have less than 10 years of experience and work in a practice providing clinic-based services were 2.3 and 3.8 times more likely to have low PA rankings, respectively. CONCLUSION: Our work underscores the importance for continued clinical veterinarian education on occupational risks associated with musculoskeletal injuries, animal bites, needle-sticks, and cuts. The fact that survey veterinarians reported a high level of zoonotic disease infection illustrates the need for education and training on proper PPE use. Further work is needed to understand why precaution awareness scores were low among this sample of participants in this study. Additional follow-up with veterinarians is recommended to assess availability of large animal handling facilities and safety practices to prevent musculoskeletal injuries.


Assuntos
Controle de Infecções/métodos , Traumatismos Ocupacionais/epidemiologia , Palpação/veterinária , Médicos Veterinários/estatística & dados numéricos , Zoonoses/epidemiologia , Adulto , Idoso , Animais , Mordeduras e Picadas/epidemiologia , Bovinos , Feminino , Cavalos , Humanos , Masculino , Pessoa de Meia-Idade , Ferimentos Penetrantes Produzidos por Agulha/veterinária , Doenças Profissionais/prevenção & controle , Exposição Ocupacional/estatística & dados numéricos , Inquéritos e Questionários , Utah/epidemiologia , Ferimentos e Lesões/epidemiologia
10.
Theriogenology ; 86(9): 2302-2311, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27650944

RESUMO

Reduced developmental competence after IVF has been reported using oocyte derived from small follicles in several species including cattle, sheep, and goats. No information is currently available about the effect of follicle size of the cytoplast donor on in vivo development after somatic cell nuclear transfer (SCNT) in goats. Oocytes collected from large (≥3 mm) and small follicles (<3 mm) were examined for maturation and in vivo developmental competence after SCNT. Significantly greater maturation rate was observed in oocytes derived from large follicles compared with that of small follicles (51.6% and 33.7%, P < 0.05). Greater percent of large follicle oocytes exhibited a low glucose-6-phosphate dehydrogenase activity at germinal vesicle stage compared with small follicle oocytes (54.9% and 38.7%, P < 0.05). Relative mRNA expression analysis of 48 genes associated with embryonic and fetal development revealed that three genes (MATER, IGF2R, and GRB10) had higher level of expression in metaphase II oocytes from large follicles compared with oocytes from small follicles. Nevertheless, no difference was observed in pregnancy rates (33.3% vs. 47.1%) and birth rates (22.2% vs. 16.7%) after SCNT between the large and small follicle groups). These results indicate that metaphase II cytoplasts from small and large follicles have similar developmental competence when used in goat SCNT.


Assuntos
Clonagem de Organismos/veterinária , Citoplasma/fisiologia , Técnicas de Maturação in Vitro de Oócitos/veterinária , Meiose/fisiologia , Oócitos/fisiologia , Folículo Ovariano/fisiologia , Animais , Ativação Enzimática , Feminino , Glucosefosfato Desidrogenase/metabolismo , Cabras , Metáfase
12.
Antiviral Res ; 108: 1-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24833276

RESUMO

Recent outbreaks of Chikungunya virus (CHIKV) infection have resulted in millions of cases of disease with significant morbidity. No approved antiviral treatments exist for the prevention or treatment of this viral disease. Infection with CHIKV results in a high rate of symptomatic disease that primarily includes a debilitating arthralgia. To model this cardinal disease manifestation, adult DBA/1J mice were challenged with CHIKV by footpad injection. Viremia and hind limb virus titers increased ∼100-fold while spleen virus increased >1000-fold within 1day post-virus infection (dpi). Footpad swelling was measured over a 10-day period, with peak swelling observed between 6 and 7dpi. Histology of the hind leg at the site of virus challenge showed evidence of myositis and synovitis starting on 5dpi. Cytokine profiling of the hind limb at the site of inoculation revealed a biphasic inflammatory response represented by an increase in IL-6, MCP-1, IFN-γ, MIP-1α, RANTES, and IL-17. To investigate the prophylactic capacity of IFN, mice were treated with mDEF201, an adenovirus-vectored IFN-α. Intranasal administration of a single 10(7)pfu/ml dose of mDEF201 administered 21days to 24h prior to infection, significantly reduced footpad swelling, virus titers in the hind leg and spleen, and several inflammatory cytokines. Efficacy was not observed when treatment was initiated 24h after virus challenge. This arthralgia model of CHIKV recapitulates relevant disease features commonly observed in human disease making it applicable to preclinical testing of therapies that target both viral replication and the associated joint disease.


Assuntos
Adenovírus Humanos/genética , Artralgia/prevenção & controle , Terapia Biológica/métodos , Febre de Chikungunya/complicações , Febre de Chikungunya/terapia , Portadores de Fármacos/administração & dosagem , Interferon-alfa/administração & dosagem , Animais , Artralgia/patologia , Febre de Chikungunya/patologia , Citocinas/análise , Modelos Animais de Doenças , Histocitoquímica , Interferon-alfa/genética , Camundongos Endogâmicos DBA , Miosite/patologia , Baço/virologia , Sinovite/patologia , Carga Viral
15.
J Vet Diagn Invest ; 24(4): 763-6, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22585959

RESUMO

In juvenile cattle, vitamin A deficiency is reported most commonly as a neurological condition; only rarely are there dermatologic manifestations. In the current study, alopecia, severe epidermal and follicular orthokeratosis, and acanthosis due to hypovitaminosis A are reported in 2 of 32 Angus calves, with a third animal suspected. Affected animals responded to vitamin A supplementation, and no additional calves displayed signs. Vitamin A acts on skin by regulating DNA transcription in keratinocytes, reducing the number of tonofilaments and desmosomes, both involved in cell-to-cell adhesion. Hence, adequate levels of dietary vitamin A are necessary for normal keratinocyte turnover, and deficiencies result in retention of keratinized cells (orthokeratosis). The present report reminds diagnosticians to consider vitamin A deficiency in cases of orthokeratotic dermatopathy in cattle.


Assuntos
Doenças dos Bovinos/metabolismo , Dermatopatias Metabólicas/veterinária , Deficiência de Vitamina A/veterinária , Animais , Biópsia/veterinária , Bovinos , Evolução Fatal , Feminino , Histocitoquímica/veterinária , Dermatopatias Metabólicas/tratamento farmacológico , Vitamina A/uso terapêutico , Deficiência de Vitamina A/metabolismo
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