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Evaluation of health and ruminal variables during adaptation to grain-based diets in beef cattle.
1995
Leedle J.A.Z. | Coe M.L. | Frey R.A.
Health and ruminal variables were intensively measured during adaptation to grain-based diets in 6 beef cattle with fistulated rumens. The cows had been maintained on prairie grass hay-supplemented diets, and were converted to a grain-based finishing ration by feeding each successive diet (diets 1-4, respectively) for a period of 7 days. Each cow was evaluated and samples were obtained 3 times each day for the first 5 days that each diet was fed. Health variables monitored were rectal temperature, pulse, respiratory and rumen motility rates, fecal consistency, demeanor, blood pH, and blood glucose and L(+) lactate concentrations. Ruminal variables monitored were pH and glucose, DL-lactate, and volatile fatty acid concentrations of rumen contents. Data were analyzed by use of a multivariate ANOVA. We determined that most of the health variables were within reference rang limits throughout the adaptation period; however, analysis of pulse and respiratory rates indicated that diets 2 and 4 were stressful. Although blood pH continually decreased during feeding of the 4 diets (7.38 to 7.30), blood L(+) lactate and glucose concentrations had large increases only within diet 4. The pH of ruminal contents decreased progressively from 6.8 to 5.3. Rumen glucose concentration was low (< 1 micromole/ml), except with diet 4 in which values were 8 times higher than for other diets. By the end of the study, the ruminal contents of all animals were acidic (pH < 5.5), and, on the basis of higher than background amounts of ruminal glucose and DL-lactate, it was determined that rumen microbial equilibrium had not yet been achieved. Analysis of results of this study suggested that ruminal imbalance could be evaluated by monitoring pulse and respiratory rates, blood pH, and blood glucose concentrations. Assessment of the rumen alone could be accomplished by monitoring the variables of rumen pH, rumen glucose, and DL-lactate concentrations.
اظهر المزيد [+] اقل [-]Effect of monensin and supplemental hay on ruminal 3-methylindole formation in adult cows after abrupt change to lush pasture.
1992
Potchoiba M.J. | Carlson J.R. | Nocerini M.R. | Breeze R.G.
The effect of feeding monensin, with or without dry hay plus wilted forage, on ruminal formation of 3-methylindole (3MI) was investigated in pastured cattle. Eighty-two cows were allotted to 3 groups. Cows of group-1 served as controls and were given a daily energy supplement (1 kg/head) without monensin for 1 day before and for 7 days after being allowed access to lush pasture. Cows of groups 2 and 3 were given the same daily energy supplement, which also contained monensin (200 mg/kg of supplement). Cows of group 3 also were fed dry hay for 5 days before the start of the study and continued to be given supplemental hay for 4 days after being allowed access to lush pasture containing a layer of wilted forage. Ruminal 3MI and indole concentrations increased on day 1 after all groups were allowed access to lush pasture. By day 7, 3MI concentration in all cows had decreased to pregrazing concentration. Indole concentration did not reach pregrazing concentration until day 10 for cows of groups 1 and 2. Group-3 cows had pregrazing indole concentration on day 7. Ruminal indole concentration did not differ (P > 0.05) between groups 1 and 2. Ruminal indole concentration was lower (P < 0.01) in group-3 cows on all sample collection days, except day 10, compared with that in the other groups. Monensin reduced (P < 0.01) 3MI formation on days 1 and 7 in group-2 cows, compared with group-1 cows. Group-3 cows had lower 3MI concentration than did group-1 cows (P < 0.01) on days -1, 1, 4, and 7. Monensin, when fed with dry hay and wilted forage, reduced (P < 0.01) 3MI formation on days 4 and 7 in group-3 cows, compared with cows that were only given monensin (group 2). Group-3 cows also had lower (P < 0.05) 3MI concentration, compared with group-2 cows on day 1. Results indicated that monensin reduced ruminal formation of 3MI. Feeding dry hay and wilted forage to cattle during the change to lush pasture resulted in further reduction in the amount of 3MI formed by ruminal microorganisms. To maximize the effectiveness of monensin in reducing 3MI formation, dry hay plus wilted forage should be fed to pastured cattle for at least 4 days after they are allowed access to lush pasture.
اظهر المزيد [+] اقل [-]Preliminary study of the pharmacokinetics and toxicopathy of deoxynivalenol (vomitoxin) in swine.
1985
Coppock R.W. | Swanson S.P. | Gelberg H.B. | Koritz G.D. | Hoffman W.E. | Buck W.B. | Vesonder R.F.
Studies on Sudan Desert sheep: 1. Effect of feeding to lambs of poor quality dry desert grass (humra) and subsequent refeeding on a high plane of nutrition on live weight growth, carcass yield and offals
1982
Gaili, E.S.E. | Mahgoub, O.
Forty–two weaned Sudan Desert lambs of both sexes were divided into three equal sex and age groups and were randomly assigned to one of three diets: Humra + limited amount of cottonseed cake and a complete ration (dura 44 % cottonseed cake 25% dry humra 29% salt 1.5% and vitamin minerals 0.5%). All diets were fed adlibitum for eleven weeks. Then differential feeding was stopped and each group was fed ad libitum on the complete ration for twelve weeks. Two lambs from both sexes were chosen at random for each nutritional treatment, and were slaughtered before the beginning of the trial. Half of the remaining lambs in each treatment was slaughtered at the end of the differential feeding period and the other half at the end of the trial. Generally, the live weight gain of lambs fed on Humra, with or without cottonseed cake, was poor whereas lambs fed on the complete ration made significantly (p
اظهر المزيد [+] اقل [-]Analytical procedure for the determination of tetracyclines in medicated feedingstuffs by liquid chromatography-mass spectrometry
2016
Patyra Ewelina | Kwiatek Krzysztof
Introduction: The article presents a rapid and simple analytical procedure for determination of four tetracyclines (oxytetracycline, tetracycline, chlortetracycline, and doxycycline) in animal medicated feedingstuffs. Material and Methods: Two-gramme samples were extracted by a Na2EDTA-McIlvaine buffer (pH 4)/methanol mixtures (40/60, v/v). The determination was achieved by liquid chromatography using a Zorbax Eclipse XDB C18 analytical column with mass spectrometer detection (LC-MS). Results: Recoveries of the antibiotics from spiked feed samples ranged from 78.2% to 113.5%. The LOD and LOQ for tetracyclines in feeds ranged from 2.8 to 4.2 and from 4.3 to 5.7 mg/kg, respectively. Conclusion: The method was successfully validated and proved to be efficient, precise, and useful for quantification of tetracyclines in medicated feedingstuffs.
اظهر المزيد [+] اقل [-]Prevalence of genetically modified soybean in animal feedingstuffs in Poland
2021
Sieradzki, Zbigniew | Mazur, Małgorzata | Król, Beata | Kwiatek, Krzysztof
Globally, genetically modified (GM) crops were grown on 191.7 million hectares in 2018, which were mostly sown with soybean, maize, cotton, oilseed rape, and rice. The most popular traits introduced through genetic modification include herbicide and pest insect resistance. The aim of this study was to identify and quantify genetically modified soybean used in animal feed in Poland. This research was based on the real-time PCR technique. All methods for GM soybean events were adopted from the EURL GMFF database of methods and previously verified to meet the minimum criteria of acceptance. Over 15 years of research, 665 samples were examined in total. The most common GM soybean event was MON40-3-2, tested for from the beginning of the investigation. Next, in decreasing order of frequency, were MON89788, MON87701, and A2704-12. In the majority of samples (606; 91%) GM soybeans were identified at a content level above the 0.9% GM content threshold for mandatory labelling. Only 59 soybean samples (9%) were identified as GM negative. GM negative results were mainly identified during the analyses in the last three years of the study, from 2017 to 2019. Our data clearly indicate that the majority of soybean used in Poland for animal feeding was genetically modified.
اظهر المزيد [+] اقل [-]Genetic characterisation of African swine fever virus in outbreaks in Ha Nam province, Red River Delta Region of Vietnam, and activity of antimicrobial products against virus infection in contaminated feed
2020
Tran, Ha Thi Thanh | Truong, Anh Duc | Ly, Duc Viet | Vũ, Thị Hảo | Hoàng, Văn Tuấn | Nguyễn, Thị Chính | Chu, Thi Nhu | Nguyen, Thi Huyen | Pham, Ngoc Thi | Nguyen, Tinh | Yersin, Andrew G. | Dang, Hoang Vu
African swine fever (ASF) was officially reported in Vietnam in February 2019 and spread across the whole country, affecting all 63 provinces and cities. In this study, ASF virus (ASFV) VN/Pig/HaNam/2019 (VN/Pig/HN/19) strain was isolated in primary porcine alveolar macrophage (PAM) cells from a sample originating from an outbreak farm in Vietnam’s Red River Delta region. The isolate was characterised using the haemadsorption (HAD) test, real-time PCR, and sequencing. The activity of antimicrobial feed products was evaluated via a contaminated ASFV feed assay. Phylogenetic analysis of the viral p72 and EP402R genes placed VN/Pig/HN/19 in genotype II and serogroup 8 and related it closely to Eastern European and Chinese strains. Infectious titres of the virus propagated in primary PAMs were 10⁶ HAD₅₀/ml. Our study reports the activity against ASFV VN/Pig/HN/19 strain of antimicrobial Sal CURB RM E Liquid, F2 Dry and K2 Liquid. Our feed assay findings suggest that the antimicrobial RM E Liquid has a strong effect against ASFV replication. These results suggest that among the Sal CURB products, the antimicrobial RM E Liquid may have the most potential as a mitigant feed additive for ASFV infection. Therefore, further studies on the use of antimicrobial Sal CURB RM E Liquid in vivo are required. Our study demonstrates the threat of ASFV and emphasises the need to control and eradicate it in Vietnam by multiple measures.
اظهر المزيد [+] اقل [-]Use of a new LC-MS method for the determination of pyrrolizidine alkaloids in feeds
2018
Kowalczyk, Ewelina | Kwiatek, Krzysztof
Pyrrolizidine alkaloids (PAs) are secondary metabolites produced by many plant species. Due to their toxicity PAs can pose a risk to human and animal health. To detect the toxic compounds in feed materials a sensitive method based on liquid chromatography coupled with mass spectrometry has been developed. PAs were extracted with sulphuric acid and purified with cation exchange cartridges. A newly developed solvent mixture consisting of ethyl acetate, methanol, acetonitrile, ammonia, and triethylamine was used to wash alkaloids from the cartridges. After evaporation the residues were reconstituted in water and methanol mixture and subjected to LC-MS analysis. The developed method was validated according to SANTE/11945/2015 guidelines. The recovery was from 84.1% to 112.9%, the repeatability ranged from 3.0% to 13.6%, and the reproducibility was from 4.8% to 18.9%. A sensitive and selective method for determination of PAs in feed materials has been developed and validated. All evaluated validation parameters were in accordance with EU Reference Laboratories document no. SANTE/11945/2015. Almost 41% of the analysed feed samples were positive for the presence of at least one PA.
اظهر المزيد [+] اقل [-]Distribution of Salmonella serovars along the food chain in Poland, 2010–2015
2017
Skarżyńska, Magdalena | Hoszowski, Andrzej | Zając, Magdalena | Lalak, Anna | Samcik, Ilona | Kwit, Renata | Wasyl, Dariusz
Introduction: Data collection on the Salmonella occurrence is crucial in effective implementation of different actions or control programmes aiming to protect consumers’ health and to reduce the level of Salmonella prevalence in farm animals. The goal was to describe Salmonella serovar distribution along the food chain in Poland during 2010–2015 and to identify their epidemiological importance.Material and Methods: Slide agglutination according to White-Kauffmann-Le Minor scheme was used to identify Salmonella serovars of 6,928 isolates originating from animals, food, feeds, and fertilisers.Results: In total, 160 Salmonella serovars were identified. Differences in serovar distribution were observed depending on animal species. Among isolates from hens, S. Enteritidis and S. Infantis were the most prevalent. Serovar pattern in turkeys differed from those in hens, with S. Kentucky, S. Newport, S. Saintpaul being the most prevalent. Monophasic S. Typhimurium was predominant in pigs. Serovars found in food reflected those observed among livestock animals. Nine out of the ten most prevalent serovars in animals and humans were also found in organic fertilisers.Conclusion: Serotyping of large number of isolates from different sources is essential for insight on emerging serovars and trends of Salmonella occurrence. This may increase the value of epidemiological data and result in updating of Salmonella control programmes to target further epidemiologically important serovars in animals and better protection of consumers’ health.
اظهر المزيد [+] اقل [-]Analytical procedure for the determination of tetracyclines in medicated feedingstuffs by liquid chromatography-mass spectrometry
2016
Patyra, Ewelina | Kwiatek, Krzysztof
Introduction: The article presents a rapid and simple analytical procedure for determination of four tetracyclines (oxytetracycline, tetracycline, chlortetracycline, and doxycycline) in animal medicated feedingstuffs. Material and Methods: Two-gramme samples were extracted by a Na₂EDTA-McIlvaine buffer (pH 4)/methanol mixtures (40/60, v/v). The determination was achieved by liquid chromatography using a Zorbax Eclipse XDB C18 analytical column with mass spectrometer detection (LC-MS). Results: Recoveries of the antibiotics from spiked feed samples ranged from 78.2% to 113.5%. The LOD and LOQ for tetracyclines in feeds ranged from 2.8 to 4.2 and from 4.3 to 5.7 mg/kg, respectively. Conclusion: The method was successfully validated and proved to be efficient, precise, and useful for quantification of tetracyclines in medicated feedingstuffs.
اظهر المزيد [+] اقل [-]