Response of barrows to space allocation and ractopamine1,2,3

Economic analysis of crossbred (Landrace × Desi) pig reared under different floor space allowances

Present experiment was conducted to study the relative economics of crossbred (Landrace×Desi) pigs with thirty six crossbred barrows reared under 3 different floor space allowances (n=12 each) having group size of 4 pigs/pen. One group (TIS) was provided floor space as per Indian Standards (0.9, 1.35 and 1.8 m2/pig for weaner, grower and finisher stages, respectively) specifications, while other two groups with 33% (T2/3) and 50% (T1/2) reduced floor space allowances. Only covered floor area was provided for all the groups. Different parameters analyzed during the study involved growth, feed conversion efficiency, requirement of water and labour for floor washing, and some other economic variables. Pigs were reared up to 28 weeks of age. Relative economics of pig rearing for three floor space allocation groups was calculated using partial budget analysis. Major performance traits, i.e. average daily gain (ADG) and feed conversion efficiency (FCE) did not differ significantly among the groups. Although body weights of T2/3 and T1/2 groups were marginally higher than TIS group. In contrary to minor savings of labour, large quantity of water was saved in T1/2 and T2/3 groups (805.4 liters/pig and 400.1 liters/pig, respectively) than TIS group between weaner and finisher stages. Additionally, input costs of  ₹` 145 and ` ₹ 96 per pig was saved by providing floor space as per T1/2 and T2/3 groups, respectively than TIS group. It can be concluded that economic gains were maximum in 50% floor space reduction group without adverse effect on performance traits of crossbred pigs.

Dietary energy level, feeder space, and group size on growth performance and carcass characteristics of growing-finishing barrows and gilts

To benefit from feeding low net energy (NE) diets, growing-finishing pigs must be able to increase feed intake to compensate for lower caloric density, but this might be difficult in pens with a high stocking density. Access to the feeder, trough space, and(or) floor area may limit voluntary feed intake. The objective of this study was to clarify the relationships among dietary NE level, feeder space, group size, sex, and interactions in growing-finishing pigs. In a 2 × 2 × 2 × 2 factorial design, 1,920 pigs (33 kg) housed in 96 fully slatted floor pens (6.1 × 2.4 m) with 2 or 3 feeder spaces, and 18 or 22 barrows or gilts per pen, were fed either low (9.2 MJ/kg) or high (9.85 MJ/kg) NE diets over 5 growth phases (Grower 1: day [d] 0 to 20, Grower 2: d 21 to 41, Grower 3: d 42 to 62, Finisher 1: d 63 to 80, Finisher 2: d 81 to slaughter). Pen body weight (BW) and average daily feed disappearance (ADFD) were measured for each growth phase, biweekly from the start of shipping and at slaughter. Warm carcasses were weighed and graded (Destron). For the entire trial, pigs fed low versus (vs.) high NE diets had 0.119 kg/d greater (P < 0.001) ADFD, but 0.556 MJ/d lower (P < 0.050) average daily caloric disappearance (ADCD), and 0.017 kg/kg lower (P < 0.001) gain-to-feed (G:F). Pens with 18 vs. 22 pigs had 0.062 kg/d greater (P < 0.001) ADFD, 0.730 MJ/d greater (P < 0.010) ADCD, and 0.029 kg/d greater (P < 0.001) average daily weight gain (ADWG). Pigs in pens with 3 vs. 2 feeding spaces had 0.051 kg/d greater (P < 0.010) ADFD, 0.511 MJ/d greater (P = 0.050) ADCD but 0.004 kg/kg lower (P < 0.050) G:F. Pigs fed low vs. high NE diets had 0.6 kg lower (P < 0.050) carcass weight and 0.9 mm lower (P < 0.050) loin depth. Pens with 18 vs. 22 pigs took 2.8 days less (P < 0.001) to reach 130 kg slaughter BW. Pens with 18 vs. 22 pigs had a 0.4 %-point decrease (P < 0.050) in dressing percentage. Feeding low vs. high NE diets reduced (P < 0.001) feed cost by Can$21.87/tonne, $3.34/pig, $0.03/kg gain, and increased (P < 0.05) gross income subtracting feed cost by $1.82/pig. Housing 18 vs. 22 pigs per pen increased (P < 0.010) ISFC by $1.98 per pig. Lack of interactions between NE level, feeder space, and group size for ADFD indicate that low NE diets can be fed to pigs even if they have lower than recommended floor area allowance during part of the finishing phase.

Interaction of space allowance and diet on growth performance and physiological responses of piglets raised in tropical conditions

Intensification of pig production in developing countries has resulted in increased number of animals per unit area leading to welfare and growth performance issues. This study was then performed to evaluate the effects of space allowance and dietary energy and amino acid content on growth performance and physiological parameters of piglets reared under tropical conditions. A total of 1280 piglets (castrated males and females) with initial body weight of 5.9 ± 0.4 kg were used. Animals were distributed in a 2 × 2 factorial arrangement composed by two space allowances (0.30 and 0.22 m²/animal) and two diets during 43 to 63 days of age (control and experimental diet with increased ME and AA content). The experimental period lasted 42 days subdivided into four phases according to the growth stage of the animals: pre-initial I (21 to 27 days of age), pre-initial II (28 to 34 days), initial I (35 to 42 days), and initial II (43 to 63 days). During pre-initial I and II, and initial I phases, pigs housed at a space allowance of 0.30 and 22 m²/animal had similar (P > 0.05) feed intake, weight gain, and feed conversion. During initial phase II, space allowance did not affect (P > 0.05) feed intake nor weight gain of the animals. Whereas, pigs fed the experimental diet had greater weight gain when compared to the control group (530 vs. 515 g/day, P = 0.03). According to our results, reducing space allowance from 0.30 to 22 m²/animal during the nursery phase (21 to 63 days of age) had negligible effects on piglet feed intake and weight gain, whereas feeding piglets with diets containing higher energy and amino levels resulted in greater weight gain.

Floor space requirement for housing and welfare of pigs under Indian perspective

Pork production in India has almost doubled from 0.204 MT to 0.402 MT in last decade (2007–08 to 2017–18). Best utilization of pen space without adversely affecting the productivity and well-being of pigs is crucial for pork sector. Most of the developed countries recommend floor space requirement of 0.15 m2/pig for weaners and South Asian countries as 0.3 to 0.5 m2/pig without any provision of open space. In India, very few studies have been carried out on space allowance in pigs. Since, Indian Standards (IS: 3916–1966) for pig housing are very old (1960s), study on the floor space requirement for individual pig in all the stages and different group sizes is very much essential for practical pig rearing. The negative impact of crowding on feed intake and growth is well documented. Higher stocking density may also adversely affect feed conversion efficiency. However, reduction in floor area (33% and 50%) in comparison to IS did not affect major performance traits. Space allowance is one of the important factors in the establishment of social rank. In European countries, the most economical allocation of pen floor space was less than the space needed for optimal performance. Reduced space allowances may lead to amplified aggression-related skin lesion scores. Thus, in space restricted environments, the dominance hierarchy becomes less stable amongst pigs and tail and ear biting are also commonly observed. Based on studies done so far it is concluded that there is scope of reduction in floor space allowance in comparison to IS specifications without compromising welfare status of pigs and further research in this area need to be encouraged.

Effects of environmental enrichment and loose housing of lactating sows on piglet performance before and after weaning

We investigated effects of loose housing of the sow during lactation and enrichment of the pen pre- and postweaning on performance of newly weaned piglets. Before weaning, piglets (n = 320) were housed in an enriched (straw, wood shavings, peat, and branches) or barren pen with a confined or loose-housed sow (n = 32). Loose-housed sows and their piglets could eat together from a family feeder, whereas confined sows and piglets had separate feeding troughs. Piglets (n = 256) were mixed postweaning, and 4 piglets from each litter were relocated to a barren pen (n = 32 pens) and 4 other piglets were housed in an enriched pen (n = 32 pens). Growth from d 15 until weaning was greater for piglets from enriched pens (4.38 ± 0.29 vs. 4.71 ± 0.21 kg/pig, P < 0.05) and tended to be greater for piglets with a loose-housed sow compared with piglets with a confined sow (4.41 ± 0.26 vs. 4.67 ± 0.24 kg/pig, P = 0.10). Preweaning feed intake was not affected by preweaning conditions (P > 0.25). Piglets from enriched preweaning pens ate more in the first 2 d postweaning than piglets from barren pens (first 48 h, barren 0.45 ± 0.05 kg/pig, enriched 0.53 ± 0.04 kg/pig, P < 0.05). Piglets relocated to an enriched pen after weaning showed a greater growth in the 2 wk after weaning (barren 5.5 ± 0.2 kg/pig, enriched 6.2 ± 0.2 kg/pig, P < 0.0001), had a profoundly reduced diarrhea prevalence than piglets housed in barren pens after weaning (barren 2.4 ± 0.4 d, enriched 1.0 ± 0.3 d, P < 0.0001), and had a greater feed efficiency (barren 0.81 ± 0.03, enriched 0.85 ± 0.02, P < 0.05). Enrichment of the preweaning environment likely stimulates development of feeding behaviors and consequently increases feed intake immediately after weaning. Providing piglets with an enriched environment after weaning positively affected postweaning growth, feed efficiency, and incidence of diarrhea, which may be caused by decreased stress or increased gut health. Enrichment of the pre- and postweaning environment seems important in improving performance and health of newly weaned pigs.

Simulação técnico-econômica da inclusão de ractopamina em dietas de suínos em terminação

Foi realizada simulação técnico-econômica a partir de resultados de publicações para avaliar a inclusão de ractopamina em dietas de suínos em terminação. Foram utilizados 18 artigos, que avaliaram níveis de 0, 5, 10 e/ou 20ppm de ractopamina na dieta, totalizando 2.991 animais. A partir dos resultados técnicos das publicações avaliadas, foram geradas equações que foram utilizadas na simulação do desempenho técnico-econômico. Verificou-se que os custos independem do sistema de receitas do produtor e oscilam de 3 a 6ppm de ractopamina adicionada à dieta. O lucro máximo foi obtido com os níveis de 10 e 12ppm de ractopamina, respectivamente, para os sistemas de receita por peso vivo e por bonificação. Os resultados evidenciam melhor desempenho econômico da utilização de ractopamina, na dieta dos suínos em terminação, pelo sistema de receita por bonificação. As análises de sensibilidade para a variação na receita dos produtores apresentam valores ótimos de 9 a 12ppm de ractopamina, com oscilação de até R$ 49,00/cabeça entre os cenários testados.

Application of broken-line analysis to assess floor space requirements of nursery and grower-finisher pigs expressed on an allometric basis1

Few issues in swine production are as complex as floor space allowances. One method for pork producers to calculate floor space allowance (A) is to convert BW into a 2-dimensional concept yielding an expression of A = k * BW(0.667). Data on ADG, ADFI, and G:F were obtained from published peer-reviewed studies. Five data sets were created: A = grower-finisher pigs, fully slatted floors, and consistent group size; B = grower-finisher pigs and fully slatted floors (group size did not need to be consistent); C = grower-finisher pigs, partially slatted floors, and consistent group size; D = grower-finisher pigs, partially slatted floors (group size did not need to be consistent); and E = nursery pigs, fully slatted or woven wire floors (group size did not need to be consistent). Each data set was analyzed using a broken-line analysis and a linear regression. For the broken-line analyses, the critical k value, below which a decrease in ADG occurred, varied from 0.0317 to 0.0348. In all cases the effect of space allowance on ADG was significant (P < 0.05). Using the linear analyses based on data with k values of < 0.030, the critical k values for the 4 grower-finisher data sets did not differ from those obtained using the broken-line analysis (0.0358 vs. 0.0336, respectively; P > 0.10); however, none of the linear regressions explained a significant proportion of the variation in ADG. The slopes for the nonplateau portion of the broken-line analyses based on percent values varied among data sets. For every 0.001 decrease in k (approximately 3% of the critical k value), ADG decreased by 0.56 to 1.41%, with an average value of 0.98% for the 5%-based analyses. The use of an allometric approach to express space allowance and broken-line analysis to establish space requirements seem to be useful tools for pig production. The critical k value at which crowding becomes detrimental to the growth of the pig is similar in full- and partial-slat systems and in nursery and grower-finisher stages. The critical point for crowding determined in these analyses approximated current recommendations to ensure the welfare of pigs.