143 research outputs found
Improved Temporal Stability of Polymethine Laser Dyes in Aqueous Solutions
Polymethine laser dyes which fluoresce in the near infrared in
organic solvents generally exhibit poor temporal stability at room
temperature. Two typical laser-pumped polymethine dyes in aqueous
solutions containing nonionic surfactants are investigated. Temporal
stability was improved 20-fold, as compared to organic solutions, with no
significant changes in laser-pumping threshold or tuning range
Silage- and forage-based diets compared to commercial diets in Ugandan pig growth
Introduction: Smallholder pig farmers in east Africa report that lack of feed, seasonal feed shortages, quality and cost of feed are key constraints to pig rearing. Commercially prepared pig diets are too expensive and there is competition for food between pigs and people. Smallholder farmers typically feed nutritionally unbalanced diets. This results in low average daily gain (ADG) and poor farmer profits. The objective was to compare the ADG of Ugandan pigs fed forage- or silage-based or commercial diets.
Materials and Methods: Local and crossbred Ugandan weaner-grower pigs were randomly assigned to commercial or forage- or silage-based diets. The forage-based diet, on an as-fed basis included specific amounts (%) of the following ingredients; avocado (25.5 kg), banana leaf (1.7), cottonseed meal (1.8), jackfruit (21.9), maize bran (9.5), sun-dried fish (3.1), sweet potato vine (36.1), limestone (0.14), salt (0.14) and vitamin/mineral premix (0.07). Silage-based diet included similar amounts of cottonseed meal, jackfruit, minerals and vitamins, but more maize bran (12.4), sun-dried fish (2.7), and ensiled sweet potato vine and tubers (60.8). Pigs were individually weighed every 3 weeks from 9 to 32 weeks of age. Pen-level ADG was compared across diets controlling for breed and starting weight using multiple linear regression.
Results: ADG of pigs fed commercial diet was higher than those fed forage- or silage-based diets between 9 and 24 weeks of age (p<0.03). Between 28 and 32 weeks, pigs fed forage-based diets had a lower ADG than those on other diets (P<0.001). Least squares mean ADG (g/pig/day) for pigs fed commercial, forage- and silage-based diets were 294, 36 and 52, respectively at 9–15 weeks; 329, 163, 212 at 15–19 weeks; 574, 112, 362 at 20-24 weeks and 1233, 694, and 994 at 28 to 32 weeks of age.
Conclusion: Forage-and silage-based diets were unsuitable for newly-weaned pigs, which may be attributed to higher than anticipated diet ash and fiber contents. However, pigs on forage- and silage-based diets grew better than those on smallholder farms once they reached 20–24 weeks and 15–19 weeks, respectively. This was when pigs were approximately 12 kg body weight. Well-balanced cost-effective diets are needed to improve pig performance in east Africa. Fresh and ensiled locally available feedstuffs can be used in diets that meet the nutrient requirements of pigs. Low-cost forage- and silage-based diets containing some zero-cost feedstuffs are needed to improve the potential for profitability of smallholder pig farming. Efficient use of these feedstuffs is required to promote sustainable smallholder pig rearing enterprises
Feeding decisions for the newly weaned pigs in East Africa are weight dependent
Introduction: Smallholder pig farmers in east Africa typically wean pigs at 6 to 8 weeks. Farmers report that commercially prepared pig diets are too expensive and therefore typically feed forage and food waste. This results in low average daily gain (ADG), especially for the newly weaned pig. The objective was to describe the weaning weights of local and crossbred Ugandan pigs purchased from smallholder farmers and to compare the growth rate of the pigs fed forage- or silage-based or commercial diets by their starting weights.
Materials and Methods: Littermate local (n = 45) and crossbred (n = 45) Ugandan pigs were purchased from 14 smallholder farmers and individually weighed at 9 weeks of age. Pigs were randomly assigned to forage- or silage-based or commercial diets, housed in pens of 3 pigs and weighed every 3 weeks. Pigs on each diet were categorized into the lightest, middle, or heaviest tertile. Pig-level ADG was compared within diet and across diet by weight tertile multiple linear regression.
Results: Average (SD) and range of body weight for 9-week-old pigs was 5.7 (1.6) and 2.8–10.2 kg for local and 8.0 (1.8) and 3.9 to 11.4 kg for crossbred pigs. From 9 to 20 weeks of age, 19 pigs gained less than 5 kg. All were fed either forage- or silage-based diets. Most pigs on these diets gained less than the smallest pigs fed commercial diet. For pigs fed forage-based, silage-based or commercial diets, the ADG of the lightest tertile of pigs was 18, -8 and 154 gm/d from 9–12 weeks and 115, 142 and 268 gm/d for 18–20 week old pigs fed forage-based, silage-based and commercial diets, respectively. Similarly, for these 3 diets, the ADG for the heaviest tertile of pigs was 32, 44, and 247 gm/d from 9–12 weeks, and 221, 332, and 319 gm/d for 18- to 20-week-old pigs. The ash levels ranged from 9–12, 12–20, and 9–11 % DM for forage-based, silage-based, and commercial diets. The high ash levels may in part explain the low ADG in the study. The highest ash levels were found in the first diets fed to the 9-week-old pigs because we included animal-grade dried fish dust rather than human-grade whole dried fish. The ash levels decreased when this change was made.
Conclusion: At 9 weeks of age, there was a wide range of weaning weights for local and crossbred Ugandan pigs purchased from smallholder farms. Farmers should be encouraged to feed commercial diet until the pigs reach 11 kg of body weight. Older and heavier pigs grow well on less expensive forage-based and silage-based diets. ADG will likely be further improved when the ash content of diets can be reduced from both farmer made and commercial diets
Indigenous pig management practices in rural villages of Western Kenya
The management of indigenous pigs in rural villages of Busia and Kakamega district, Western Kenya, is discussed. Data on husbandry practices, challenges and farmers knowledge on T. solium taeniosis / cysticercosis were gathered using questionnaires administered in face-to-face interviews. Pigs were examined for cysticercosis using the lingual palpation method. Data were managed in Stata®. Majority of the farmers were aged 30-50 years (44%), and were mostly women (69%). Years of pig keeping experience was higher in Kakamega (11.4±8.7) than it was in Busia (6.3±5.6) (P50%) during the planting (91%; 263 / 290), growing (90%; 263 / 290) and crop harvesting seasons (78%; 227 / 290). Prevalence of pig cysticercosis was 4.5%. Piglets were significantly cheaper in Busia (Ksh 509±57) than in Kakamega (Ksh 777±174) (P<0.05). Indigenous pig management in Western Kenya is reportedly poor. Improved knowledge coupled with changes in local husbandry practices would improve productivity, increase family incomes and safeguard the community from potential health risks associated with pig rearing
Investigating biosecurity risks associated with the delivery of feed to swine farms
Introduction
Biosecurity protocols reduce the introduction and spread
of pathogens among swine farms. For pigs, biosecurity
ensures market stability, maintains export opportunities,
and controls spread of production and public health
diseases. Salmonella, the second most common cause of
bacterial foodborne illness, causes gastrointestinal
illness. Pigs can be asymptomatic carriers of the bacteria
and pork products are a known source of salmonellosis
in humans. Salmonella have been isolated from pigs,
boots, flies, rodents, bird feces, feed, feed-ingredients,
and feed trucks. The objective was to identify
management factors to reduce the risk of disease spread
among swine farms through feed trucks.
Materials and Methods
The study was conducted in two phases - the first phase
included a series of focus groups and key-informant
interviews; discussions held with swine producers and
feed company personnel explored the protocols currently
in place that reduce the risk of disease spread through the
delivery of feed. Participants were asked to identify
possible management changes that could further reduce
the risk, and to rate these ideas in terms of their effect on
disease control, and feasibility based on implementation
and economics. This information was used to structure
the second phase of the study – a pilot study. The pilot
study was conducted over 6 weeks in the winter of 2013,
and included 40 feed truck drivers from 3 Ontario feed
companies. Truck drivers filled out log sheets as they
delivered feed to swine farms, and provided information
about the prevalence of the identified biosecurity risks
during the day-to-day delivery of feed. Drivers were
randomly assigned to be in either the treatment or
control groups. Drivers in the control group delivered
feed as they normally do. Drivers in the treatment group
were: i) asked not to enter the barn unless absolutely
necessary, and ii) were provided with re-usable,
washable rubber over-shoes and were asked to wear a
clean pair at each farm when they felt safe doing so. Chisquared
tests were used to compare the usage of clean
boots between drivers in the treatment and control
groups.
In total, 40 drivers from 3 companies, delivering feed to
2202 farms over 6 weeks (in the winter) collected
descriptive data on the factors and compared use of
different boots.
Results
The factors followed by the proportion of farms and
drivers where the factor was found were found as
follows: Most farms were: keeping areas (driveway, feed
bin and barnyard) clean of mud and manure (82%), and
dead-stock (91%) was appropriately disposed of and not
visible to the driver. Some farms had an outbuilding to
deliver bagged feed (24%). Other factors that were
identified that producers should work on were to provide
farm boots and coveralls for the driver if the driver
needed to go into the barn, ordering the correct amount
of feed to decrease the numbers of deliveries (or
frequencies of deliveries) of feed, and notifying feed mill
of a disease outbreak on the farm. Feed truck driver
factors included wearing a separate pair of clean,
disinfected, dried boots (25%) and gloves (50%) at each
farm that is visited (even if the driver does not go into
the barn, remaining outside the barn (92%); washing the
steering wheel (49%), floor mat (77%) and outside of the
truck (32%) every 24 hours. From these results, it may
be advisable to increase the frequency of washing the
truck. Another factor identified was for the driver to
know and follow the farm biosecurity protocols. Half of
the time, the driver left the feed bill outside barn (54%).
Drivers given disinfected rubber boots were more likely
to wear these on farms (42%) than plastic disposable
boots (4%) (P<0.05). These drivers were also more
likely to wear disinfected rubber boots than the control
drivers (11%) (P<0.001).
Conclusions and Discussion
Biosecurity is a responsibility that is shared among all
members of the industry. Feed personnel were
encouraged to know more about disease transmission.
Acknowledgments
Canadian Swine Health Board for funding, feed
company personnel and producers for participation
Increasing smallholder pig farmers' adaptive capacity: Low-cost balanced diets for East African pigs using livestock and plant co-products
By acquiring livestock poor farmers can ascend out of poverty. Pigs require minimal inputs
and raising them is often within disadvantaged members of society’s means. In East Africa,
2.2 million pigs are raised by resource-poor, subsistence farmers most with under 2 hectares of
cropland. They typically raise 1–4 pigs to pay for school, medical costs, food, and seeds, but
pig productivity is low. Lack of feed, seasonal feed shortages and unbalanced diets contribute
to slow growth, resulting in compromised earnings from pig-raising.
We estimated East African pig feedstuff nutrient composition through nutrient analysis and
from literature. Seasonal availability was identified by local experts. Performance results from
local-breed pig feeding trials were used to adjust the NRC (2012) nutrient requirement model
for growing-finishing pigs. Local pigs’ nutrient requirements under typical management conditions
(intestinal parasites present and free-ranging) were estimated. A least-cost diet formulation
programme was used to generate diets minimising cost and human/pig competition
for food, maximising agricultural co-products and forages use, considering seasonal availability,
and satisfying minimal requirements for digestible energy 2960 kcal per kg of dry matter
[DM]), calcium, standardised total tract digestible phosphorous, standardised ileal digestible
crude protein and lysine (0.28, 0.13, 8.5, and 0.58% of DM respectively)
Feedstuffs availability differed between November-February; June-August; and March-May
plus September-October. Estimated growth performance potential of local pigs is less when
free-ranging, or intestinal parasite infected, than when restrained and non-infected (80; 217;
and 259 g per day respectively) A typical least-cost diet for June-August (all as % of DM) is:
maize flour 20.6; cassava leaf 20.0; sweet potato vine 19.2; ripe avocado 15.0; Bidens pilosa
7.9; limestone 7.7; molasses 5.0; cattle blood 3.9; Amaranthus spinosus 0.3; table salt 0.24;
premix 0.10. Sun-dried fish (Rastrineobola argentea) and grist mill waste are available all year
as substitutes for seasonably available ingredients e.g avocado and sweet potato vine.
Use of such diets will enable continuous pig feeding during all seasons, thereby increasing
farmer resilience. Their use will improve pig performance resulting in increased farmer income,
enabling poverty alleviation, improved food security, human health and nutrition, and
investment in other livelihood ventures to further increase resilience
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