Effect of milk deprivation during the lactation period on performance and digestive enzyme activities of the piglets following weaning

Posted in: Pork Insight Articles, Welfare by admin on September 25, 2006 | No Comments

Post-weaning performance of piglets from systems where lactation is disrupted (e.g. from multisuckling systems) is superior to conventionally reared piglets. The objective of this study was to establish whether restricted growth prior to weaning caused by disruption of suckling was an important factor in post-weaning performance and also whether there were related changes in gastro-intestinal development. Ten litters of eight piglets were used in a split-plot design. Half of each litter (limited suckling, LS) had suckling disrupted by separation from their dam for 7 h/day from day 14 to 28 after farrowing. The remainder of each litter was allowed to suck normally (normal suckling, NS). The same amount of creep feed was offered to LS piglets as consumed by NS littermates on the previous day. There were no differences in weight between LS and NS piglets at 14 days of age, but restricting access to the sow reduced weaning weight at 28 days of age (7.96 v. 9.00 kg; LS v. NS; P , 0.01; s.e.d. 0.23). Feed intakes were greater for LS than NS piglets over the first 28 days post weaning, particularly in the 1st week after weaning when feed efficiency was also improved (0.91 v. 0.62 kg gain per kg feed; P , 0.01; s.e.d. 0.08). As a result, LS piglets grew more rapidly in the first 28 days post weaning, particularly in the first 7 days after weaning. Subsequent performance to 8 weeks was similar for both groups. Digestive organ weights were not different at 2 and 9 days after weaning; nor were small intestine specific enzyme activities significantly different ( P . 0.05). Pancreatic trypsin activity was, however, greater ( P , 0.01) for LS pigs on both days 2 and 9 post weaning. In conclusion the restriction of growth as a result of limited suckling itself is an important factor in determining post-weaning performance and may be related to development of pancreatic trypsin activity.

Sandra Edwards

Sow shoulder lesions: Risk factors and treatment effects on an Ontario farm

Posted in: Pork Insight Articles, Welfare by admin on September 12, 2006 | No Comments

Farrowing sows spend the majority of their time laying on their side, and as a result can develop lesions on their shoulders. The sows on an Ontario farm were monitored on the development of lesions on different floor types. Lesions were scored on a scale of 0-4 on size and severity, and if lesions were 3 or 4 sows were assigned to a treatment group. The treatment involved including a steel plate or a rubber mat on the flooring , or leaving it as a control. There was an increase in risk of lesion formation in sows with a body condition score below 3 by 3.7 times (P<0.05), a flank-to-flank measurement of 94-104cm by 2.8 times (P<0.05), and an increase of 1kg to weaning weight  by 1.1 times (P<0.05). As well, Landrace or Duroc sows were more likely to develop lesions than Yorkshire sows, as were first or fifth and above parity sows. The sows with the stainless steel plate treatment had an average healing time of 39 days, the control group had 32 days, and the rubber mat group had 25 days. The cost for rubber mats with multiple uses becomes $0.09, and the benefit to sow welfare is significant enough to consider implementing.

AN EVALUATION OF ALTERNATIVE SYSTEMS FOR REDUCING THE TRANSMISSION OF PORCINE REPRODUCTIVE AND RESPIRATORY SYNDROME VIRUS BY AEROSOLS

Posted in: Air Filtration, Pork Insight Articles by admin on August 31, 2006 | No Comments

The porcine reproductive and respiratory syndrome (PRRS) virus has been proven to spread through the air. The most proven way to stop this aerosol spreading of the virus is to install HEPA filters where air enters the barn. Although this method is effect it can also be costly. This report evaluates effective inexpensive alternatives to stoping the PRRS virus. Pigs were held in a recipient chamber where air was filtered into by a fan from the first chamber. The air was PRRS positive and was misted in to the  first chamber. The low costs filter being tested (control) was made of mosquito netting, 2 fiberglass furnace filters and 2 electrostatic furnace filters. The HEPA filtration system utilized a pre-filter screen, a bag filter and a HEPA filter. The bag filtration system involved the use of a MERV 14 rated filter. The 95% DOP @ 0.3 μm filtration system involved a pleat-in-pleat V-bank disposable filter having a 95% DOP efficiency rating at particles > 0.3 μm. Aerosol transmission of PRRSV occurred in 10/10 replicates (control), 0/10 replicates (95% DOP @ 0.3 μm filtration), 4/10 replicates (2x-low cost filtration) and 0/10 replicates (HEPA filtration). The HEPA filter seems to be the most effective method for stopping the spreading of PRRS although the 95% DOP maybe a more cost efficient method.

Production porcine – Santé animale Les distances séparatrices

Posted in: Air Filtration, Pork Insight Articles by admin on August 27, 2006 | No Comments

Lors de la tournée provinciale du Bureau d’audiences publiques sur l’environnement (BAPE) relativement à la consultation publique sur le développement durable de la production porcine au Québec, qui s’est déroulée entre septembre 2002 et septembre 2003, plus de 9 000 personnes ont assisté et participé à la centaine de réunions. Près de 400 mémoires y ont été présentés. Dans son rapport, la Commission vient à la conclusion que les données disponibles ne sont pas suffisamment précises et scientifiquement fondées pour proposer des normes de distances séparatrices.

Je ne veux pas aborder ici la question des distances séparatrices entre les activités agricoles et les périmètres des villes, les résidences, les chemins publics ou les activités récréatives ou industrielles de toutes sortes. Je veux plutôt aborder les risques de contamination aérienne entre élevages de porcs.

Les vétérinaires savent depuis longtemps qu’il est difficile d’obtenir une stabilité sanitaire à long terme dans les élevages qui sont situés près les uns des autres. Cette observation est encore plus fréquente depuis l’apparition…

Component and Factor Analysis of Pork Farm Odour using Structural Learning with the Forgetting Method

Posted in: Ontario Pork, Pork Insight Articles by admin on August 23, 2006 | No Comments

There have been many studies on the modelling of pork farm odour by analysing the chemical components in odorous air. It is suggested that the component analysis approach should be extended to factors such as temperature, relative humidity, and airflow speed. A relative contribution analysis of potential odour components and factors to the perception of odour would allow identification of significant odour components and major contributing factors. Odour reduction practice for pork farms could then be directed towards the significant components and factors, thus improving the efficiency in developing odour measurement and reduction technologies. It is generally accepted that neural networks have several advantages over conventional techniques, for instance, their ability to automatically learn the relationship between the inputs and outputs without any previous knowledge of the system being studied, their powerful generalisation ability, and their capability of handling non-linear interactions. However, typical neural network models suffer from the so-called ‘black box’ problem, i.e. it offers no information about the system other than the input/output relationship. In this paper, existing methods for odour strength prediction were reviewed, and a neural network based multi-component multi-factor odour model was developed. To reveal the relative contribution of the inputs, the neural network was trained using an algorithm called structural learning with forgetting. By applying the structural learning with forgetting based algorithm, unnecessary neural connections faded away and a skeletal network emerged. The resulted skeletal network enabled an analysis of the contribution of components and factors. The effectiveness of the proposed approach was demonstrated by simulation and comparison studies.

New Conservation Till Manure Nutrient Delivery System 2004-2006

Posted in: Ontario Pork, Pork Insight Articles by admin on August 21, 2006 | No Comments

Residue cover along with manure application can reduce erosion and phosphorus runoff significantly, although this minimum tillage can limit crop yields. To overcome these limitations effective nutrient placement should be adopted. A zone-jection system with crop nutrients applied as manure, narrowed the yield gap that can occur for no-till corn following a poor crop. There was no evidence of increased nitrate leaching, even at sites where excess N was applied. The absence of large amounts of N in either the soil or soil solution may be related to efficient N use and even luxury consumption of N by the crop and excess accumulation in stalks. It was found that the stalk can represent a significant sink for N in cases of over application. The N contained in stalks would likely be released slowly over time or incorporated into soil organic matter given its wide C/N ratio. Zone-jection proved a viable system for producing good crop yields and benefiting the environment through efficient nutrient use, as well as control of runoff, erosion and odors.

Selection of sex specific DNA aptamers to sperm

Posted in: Ontario Pork, Pork Insight Articles by admin on August 15, 2006 | No Comments

Currently sorting mammalia sperm is limited due to the damage it inflicts on sperm and costs and time associated with it are unrealistic. But the ability to sort sperm and be able to determine gender based on sperm can have huge implications to large farms and is desirable.  Sex-specific markers are needed to improve current methods and develop a working sperm sorting system. This project uses aptamers to help detect molecules. Tests were carried out to get aptamers to bind to boar sperm, and a high binding efficiency was achieved. Assessment of the aptamers found that they were in both the nuclear and cellular extract. Aptamers were then selected to pre-sorted bull sperm. The selection was monitored and then assessed. X-aptamers were found to have more binding ability than Y-aptamers.

Prevalence of resistance to 11 antimicrobials among Campylobacter coli isolated from pigs on 80 grower-finisher farms in Ontario

Posted in: Ontario Pork, Pork Insight Articles by admin on | No Comments

We carried out a cross-sectional study to investigate antimicrobial resistance patterns of Campylobacter coli isolated from Ontario grower-finisher pigs. From January to June 2004, 1200 samples were collected from 80 farms by obtaining a constant number (15) of fecal samples per farm. Susceptibility of the isolates to 11 antimicrobial drugs was determined by the agar-dilution technique. The overall prevalence of resistance to 1 or more antimicrobials among the isolates was 99.2%. High levels of resistance were observed for azithromycin, clindamycin, erythromycin, streptomycin, and tetracycline: 91.7%, 82.5%, 81.4%, 70.7%, and 63.7%, respectively. For sulfamethoxazole, ampicillin, and nalidixic acid, resistance was observed in 40.3%, 26.6%, and 22.7% of the isolates, respectively. Although at very low levels, resistance was observed for ciprofloxacin (a fluoroquinolone), chloramphenicol, and gentamicin: in 2.4%, 1.7%, and 0.2%, respectively. Many of the isolates (29.7%) were resistant to 5 antimicrobials, the most common being azithromycin, clindamycin, erythromycin, streptomycin, and tetracycline. Isolates from the same farm showed at least 5 patterns of resistance. Results from this study indicate high levels of resistance to the antimicrobial drugs most commonly used in the Canadian swine industry (macrolides, lincosamides, and tetracyclines) among C. coli isolated from grower-finisher pigs in Ontario. Macrolides and fluoroquinolones are the drugs most commonly used to treat severe human campylobacteriosis. Fortunately, at present, there is little resistance to fluoroquinolones among C. coli from pigs in Ontario.

A Growth-Maturation System That Enhances the Meiotic and Developmental Competence of Porcine Oocytes Isolated from Small Follicles

Posted in: Ontario Pork, Pork Insight Articles, Production by admin on June 28, 2006 | No Comments

In livestock, most of the follicles on the ovarian surface are small follicles. A procedure that supports the in vitro growth and maturation of these small follicle-derived oocytes may offer a new source of useable oocytes for both biotechnological and fundamental research purposes. The objective of the current study was to test the hypothesis that providing a more growth-supporting and less maturation-promoting environment during the first phase of small follicle-derived oocyte maturation may improve oocyte competence for meiosis and embryo development upon activation. In our small follicle-derived oocyte growth-maturation system (SGM group), cumulus-oocyte complexes (COCs) from small follicles (1–3 mm) were first cultured in oocyte growth medium for 24 h, then in oocyte maturation medium for 20 h. As controls, COCs from small (SM group) and large (LM group) follicles were cultured using a conventional in vitro maturation (IVM) approach in which they were directly cultured in oocytematurationmedium. At 24 h of culture, the percentage of small follicle-derived oocytes that underwent germinal vesicle breakdown (GVBD) in the SGM group was comparable to that of large follicle-derived oocytes (LM group) but was significantly higher than that of the SM group (P <0.05). At 44 h of culture, compared to 36% in the SM group, 55% of the SGM group oocytes reached metaphase II (MII; P <0.05). In addition, the level of cyclin B in oocytes of the SGMgroup was comparable to that of oocytes from LM group and was significantly higher than that of oocytes from the SM group (P <0.05).When activated and in vitro fertilized (IVF), 7.3 and 9.0 times more parthenogenetic and IVF embryos developed to blastocyst stage in the SGMgroup than in the SMgroup (P < 0.05). ThemRNA expression levels of three developmentally important genes—DNA-methyltransferase 1, Pou domain class 5 transcription factor 1, and Fibroblast growth factor receptor 2—in embryos of the SGM group were comparable to those of embryos developed from the LMgroup, whereas they were significantly lower in those of the SM group (P < 0.05). Our data suggest that the oocyte growthmaturation system facilitates the final stage of oocyte growth and thus resulted in better oocyte nuclear, cytoplasmic maturation, and developmental competency compared with the conventional direct oocyte maturation system.

Positive handling in late pregnancy and the consequences for maternal behaviour and production in sows

Posted in: Pork Insight Articles, Welfare by admin on May 23, 2006 | No Comments

Negative handling increases the stress for sows, but positive handling can actually increase the sow productivity. However, the studies on positive handling have largely been conducted over a longer time frame, and this study looked at acute positive handling before farrowing. The goal was to determine if acute positive handling can increase sows’ maternal behaviors. Sows were scored out of 6 for confidence 12 days before farrowing, then half of the group received positive handling for the 12 days. Positive handling included giving a sow feed nut, petting neck and head, and quiet talking. The control sows received minimal human contact. Behavior was recorded by video from two days before, to two days after farrowing on 11 high confidence and 11 low confidence sows. There was no difference in nest building behavior, nursing behavior, posture changes or bar chewing between control and treatment sows. Farrowing duration, piglet mortality, and piglet weight gain were likewise unaffected. Although short-term positive handling had little detectable effect, sows with an initial higher confidence score did have shorter farrowing duration, and spent more time resting prior to farrowing. Finally, sows with low confidence scores had reduced fear towards humans when part of the treatment, even after only two weeks of positive handling.