Background Antibiotics (AB) are an important tool to tackle infectious disease in pig farms; however some research indicates that their frequent mis/over-use may contribute to the development of antibiotic resistance and the WHO has declared that this issue should be addressed. Little is known about the long term consequences of withdrawing prophylactic AB from pig feed; hence we aimed to assess its effects on performance and health of pigs from weaning to slaughter. Six batches of 140 pigs each were monitored on a commercial farm through the weaner and finisher stages to slaughter. In-feed antibiotics were not added to the feed for half of the pigs (NOI) and were added in the other half (ABI) within each batch for the whole weaner stage. Individual pigs in both treatments were treated with parenteral administrations if and when detected as ill or lame. Productive performance, parenteral treatments and mortality were recorded on farm and the presence of respiratory disease was recorded at slaughter. Pen was considered the experimental unit. Results ABI pigs showed higher growth ( P = 0.018) and feed intake ( P = 0.048) than NOI pigs in the first weaner stage but feed efficiency was not affected (NOI = 1.48 vs. ABI = 1.52). Despite an initial reduction in performance, NOI pigs had similar performance in finisher stage (ADG: NOI = 865.4 vs. ABI = 882.2) and minimal effects on health compared to ABI pigs. No difference between treatments was found at the abattoir for the percentage of pigs affected by pneumonia, pleurisy, pleuropneumonia and abscesses ( P > 0.05). Mortality rate was not affected by treatment during the weaner stage ( P = 0.806) although it tended to be slightly higher in NOI than ABI pigs during the finisher stage ( P = 0.099). Parenteral treatments were more frequent in NOI pigs during the weaner stage ( P < 0.001) while no difference was recorded during the finisher stage ( P = 0.406). Conclusions These data suggest that the removal of prophylactic in-feed antibiotics is possible with only minor reductions in productive performance and health which can be addressed by improved husbandry and use of parenteral antibiotics.
A Dess-Martin Periodinane (DMP) mediated oxidative rearrangement reaction was uncovered. The reaction proceeds via oxidation of a β-hydroxy thioester to a β-keto thioester, followed by an α-hydroxylation and then further oxidation to form a vicinal thioester tricarbonyl. This product then rearranges, extruding CO, to form an α-keto product. The mechanism of the rearrangement was elucidated using C labelling and analysis of the intermediates as well as the products of the reaction. This efficient process allows for easy preparation of α-keto thioesters which are potential intermediates in the synthesis of pharmaceutically important heterocyclic scaffolds such as quinoxalinones.
The effects of food intake during lactation and post weaning on the reproductive performance and hormone and metabolite concentrations of primiparous sows. AbstractThe objective of this study was to investigate the effect of low food intake on post-weaning fertility and hormone concentrations in primiparous sows. One hundred and forty primiparous sows (Landrace X Large White) were randomly assigned to one of four treatment groups: (A) restricted to 3 kg food per day during lactation and 2 kg food per day post weaning (no. = 36); (B) restricted to 3 kg food per day during lactation and ad libitum feeding post weaning (no. = 33); (C) ad libitum feeding throughout with a mean voluntary food intake of 3-7 kg/day during lactation (no. = 36); and (D) ad libitum feeding throughout with a mean voluntary food intake of 4-9 kg/ day during lactation (no. = 35). Litters were standardized at eight to 10 pigs at 2 days post partum and were weaned at 27-2 (s.e. OS) days post partum. After weaning, sows were observed twice daily for signs of oestrus and were mated on the day(s) of standing oestrus. Six sows from each group were fitted with indwelling jugular cannulae 2 days before weaning. Blood samples were collected 1 day before weaning (W-l), 1 day after weaning (W+l) and 4 days after weaning (W+4), and these sows were slaughtered on W+4. Ovaries were recovered, follicles and corpora lutea were counted, and folUcular fluid collected. Sows given food at a restricted level (groups A and B) lost more backfat during lactation than sows given food ad libitum (groups C and D) (P < 0-01). Piglet weaning weights, weaning to conception intervals and the proportion of sows ovulating by W+4 were not significantly different among groups. In sows that did not ovulate, numbers of large follicles were not significantly different among groups but the low food intake (groups A, B and C) sows had more medium-sized follicles than high food intake (group D) sows (P < 0-01). FolUcular fluid concentrations of oestradiol, progesterone and insulin-like growth factor-1 (IGF-1) did not differ among groups (P > 0-05). Plasma non-esterified fatty acids concentrations were greater in groups C and D than in groups A and B on W-l, W+l and W+4. Serum insulin and plasma glucose concentrations were lower in groups C and D than in groups A and B on W-l and W+l, but were similar among groups on W+4. Serum growth hormone concentrations were lower in group D than group A and B on W-l and W+l but not W+4. Concentrations of IGF-1 in serum were greater in groups C and D than groups A and B on W-l and W+l but not W+4. It is concluded that low food intakes during lactation and post weaning affected body condition, serum hormones and metabolites and ovarian function of primiparous sows without dramatically affecting ovarian hormones or reproductive performance.
Pig production in Ireland has gone through enormous changes during the past 60 yr, from pigs being primarily produced as a sideline on dairy farms, to an industry with one of the highest average herd sizes in Europe. This happened in part due to external pressure on the industry, whereby economies of scale were needed to compete with pigs produced in other countries, but largely due to the instigation of national programmes to support the pig industry through research, education and knowledge transfer. These efforts helped producers to take advantage of genetic improvements and monitor their own performance over time, as well as allowing for benchmarking of the national herd against other countries. The research programme initiated in the 1960s continues to grow and expand, providing the pig industry with internationally renowned data and knowledge in the areas of nutrition, animal welfare, the environment and energy use. Recent initiatives such as the establishment of the Teagasc and Irish Farmers Association Pig Joint Programme, and a Pig Health Check section in Animal Health Ireland, will help to promote further cross-collaboration between stakeholders in the pig industry, and enable it to rise to the challenges of the years ahead.
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