Post-weaning Phase Research Articles

Invited review: Aspects of gastrointestinal tract growth and maturation in the pre- and postweaning period of pigs

The growth and development of the gastrointestinal tract (GIT) of the young pig, both before and after parturition, is critical for the ani-mal’s future growth and development, efficiency of feed conversion to body depots, and, ultimately, its survival. The perinatal development of the GIT encompasses a prenatal phase, a neonatal phase, and the postweaning phase, which is associated with the adaptation of the GIT to utilize solid feed after the piglet is weaned. The consumption of colostrum, initially, and then milk after birth provides nutrients and compounds for piglets that are critically important as stimuli and substrates to the GIT that in turn evoke a suite of anatomical, immunological, biochemical, physiological, and regulatory processes that advance the overall maturity of the GIT. However, at weaning the combined influence of the various stressors imposed causes a hiatus in the growth and development of the GIT, such that the newly weaned pig endures a “growth check” while exposing it to a greater disease and health risk. Low and variable feed intake is a major outcome of the weaning process, but nevertheless, there are numerous nutritional/manage-ment interventions producers can implement in an attempt to overcome this major issue. This review summarizes some major aspects of, and influences on, GIT growth, development, and maturation in the pre- and postweaning period of pigs, demonstrating that postnatal influences occur in utero and that evolution of the GIT continues to occur after weaning.

Spray dried plasma as an alternative to antibiotics in piglet feeds, mode of action and biosafety.

The use of growth promoting and therapeutic antibiotics in piglet feed has been a concerning subject over the last few decades because of the risk of generating antimicrobial resistance that could be transferred to humans. As a result, many products have been proposed as potential alternatives to the use of antibiotics, and among these, spray dried plasma is considered one of the most promising. However, there have been concerns about its biosafety, particularly during periods of emergence or re-emergence of swine diseases in different regions of the world, such as the recent porcine epidemic diarrhea virus outbreak in North America. The objectives of this paper are to review recent publications about the use of spray dried plasma as an alternative to antibiotics in weaned pig diets, the possible mechanisms of action of spray dried plasma, and the existing evidence related to the biosafety of spray dried animal plasma. Particular attention is given to studies in which spray dried plasma has been directly compared to antibiotics or other alternative antimicrobial products. Several studies on the possible modes of action for spray dried plasma, such as preservation of gut barrier function or modulation of the immune response, are also reviewed. Finally, the paper focuses on the review of the existing studies on the risks of disease transmission with the use of spray dried plasma from porcine origin. Overall, spray dried plasma is a promising alternative to in-feed antimicrobials for piglets, particularly during the early stages of the post-weaning phase. Additionally, there is enough evidence to support that commercial spray dried porcine plasma is a safe product for pigs.

Comparison of protein and energy supplementation to mineral supplementation on feeding behavior of grazing cattle during the rainy to the dry season transition.

The aim of this study was to evaluate the effects of protein-energy or mineral supplementation on the ingestive behavior of dairy steers on pasture in the post-weaning phase during the rainy to dry season transition. Twenty-two ½ Holstein–Zebu dairy steers with an average initial body weight of 234 ± 16 kg were distributed into a completely randomized design into two groups: protein-energy supplementation and mineral supplementation offered ad libitum. The steers receiving protein-energy supplementation showed higher (P < 0.05) intake of dry matter (DM) and neutral detergent fiber (NDF) than those fed diets composed of mineral salt only. In addition, the animals that received protein-energy supplementation had longer period in grazing and spent on average more time per period eating at the trough (P < 0.05), however no significant differences were observed in the time per period in rumination and time per period in idle (P > 0.05). The supply of protein-energy supplement does not change the feeding behavior, except for an increase in the time spent feeding at the trough. The intake of protein-energy supplement improved the of DM and NDF feed efficiencies in grazing cattle during the rainy to the dry season transition.

ADITIVOS ANTIBIÓTICO, PROBIÓTICO E PREBIÓTICO EM RAÇÕES PARA LEITÕES DESMAMADOS PRECOCEMENTE

Resumo Objetivou-se avaliar a adição do prebiótico mananoligossacarídeo (MOS 0,2%), probiótico (Bacillus subtilis 30g/tonelada) e antibiótico (bacitracina de zinco 125g/tonelada) em rações para leitões na fase de creche. Utilizaram-se 80 leitões (Danbread x Agroceres), sendo 40 machos e 40 fêmeas, com peso inicial de 7,1±0,0175kg, distribuídos em delineamento de blocos ao acaso, com quatro tratamentos e cinco repetições: 1 - controle; 2 - prebiótico; 3 - probióticos; e 4 - antibiótico. As variáveis avaliadas foram ganho de peso diário (GPD), consumo de ração diário (CRD), conversão alimentar (CA), consistência fecal e leucometria global. Aos 43 dias de idade, os animais apresentaram o mesmo ganho de peso (P&gt;0,05), porém, a dieta contendo prebiótico aumentou o consumo (P&gt;0,05); a conversão alimentar foi melhor na dieta controle (P&lt;0,05). No período de 54 dias de idade dos animais, não houve diferença para ganho de peso diário (P&gt;0,05), consumo de ração diário (P&gt;0,05) e conversão alimentar (P&gt;0,05). Não houve diferença para consistência fecal (P&gt;0,05). O número de leucócitos aumentou aos 32 dias de idade, quando as dietas contendo prebióticos e probióticos foram utilizadas (P&gt;0,05). A ração contendo prebiótico aumentou o número de monócitos (P&lt;0,05) e a dieta contendo antibiótico proporcionou maior número de basófilos (P&lt;0,05), aos 36 dias de idade dos animais; o número de linfócitos não foi alterado pelas dietas experimentais (P&gt;0,05). As dietas não promoveram alterações nas imunoglobulinas IgA, IgM e IgG (P&gt;0,05). Conclui-se que o uso de prebióticos, probióticos e antibióticos não influenciou o desempenho dos animais dos 22 aos 54 dias de idade.

Substitution of soybean meal for cottonseed meal in multiple supplements for grazing beef heifers in the dry season

&lt;p&gt;Objetivou-se avaliar o efeito da substituição do farelo de soja pelo farelo de algodão em suplementos múltiplos sobre as características nutricionais e desempenho produtivo de novilhas de corte em fase de recria em pastagens de &lt;em&gt;Brachiaria decumbens &lt;/em&gt;no período da seca. Foram utilizadas 24 novilhas de corte nelore com idade e peso médio inicial de 8 meses e 210±6 kg, respectivamente. O delineamento foi inteiramente casualizado com quatro tratamentos e seis repetições. Os suplementos continham aproximadamente 30% de proteína bruta (PB) e substituição progressiva do farelo de soja pelo farelo de algodão em 0, 50 e 100%. Aos animais do tratamento controle foi fornecida apenas mistura mineral &lt;em&gt;ad libitum &lt;/em&gt;e aos demais tratamentos foram fornecidos 1,0 kg/animal/dia de suplemento. Não houve diferença de GMD entre os animais suplementados e os animais controle (P&amp;gt;0,10). A suplementação aumentou apenas o consumo de proteína bruta (PB) (P&amp;lt;0,10). O nível de substituição de farelo de soja pelo farelo de algodão não afetou (P&amp;gt;0,10) o consumo nos animais suplementados. A suplementação ampliou os coeficientes de digestibilidade aparente (P&amp;lt;0,10) da MO, PB, CFN e NDT com exceção do EE e da FDNcp (P&amp;gt;0,10). Observou-se efeito linear positivo (P&amp;lt;0,10) do nível de substituição de farelo de soja pelo farelo de algodão sobre a digestibilidade da MO, CNF e NDT. Houve efeito da suplementação e do nível de substituição (P&amp;lt;0,10) sobre o teor de nitrogênio ureico no soro e nitrogênio ureico na urina. Não houve efeito da suplementação e do nível de substituição sobre o fluxo de nitrogênio microbiano ao intestino (NMIC) e eficiência de síntese de proteína microbiana (EFM) (P&amp;gt;0,10). Foi verificado efeito linear decrescente (P&amp;lt;0,10) da substituição sobre a relação nitrogênio microbiano/ nitrogênio ingerido (NMICR). Conclui-se que a substituição do farelo de soja pelo farelo de algodão em suplementos múltiplos durante a época seca não prejudica o desempenho produtivo de novilhas de corte.&lt;/p&gt;

ADITIVOS ANTIBIÓTICO, PROBIÓTICO E PREBIÓTICO EM RAÇÕES PARA LEITÕES DESMAMADOS PRECOCEMENTE

The objective of this study was to evaluate the addition of the prebiotic mannan oligosaccharide (MOS 0.2%), probiotic ( Bacillus subtilis 30g/ton) and antibiotic (Bacitracin zinc 125g/ton) to piglets’ feed in the post-weaning phase. Eighty (Danbread x Agroceres) pigs were used, that is, 40 males and 40 females, with initial weight of 7.1 ± 0.0175 kg. A randomized block design was used with four treatments and five replicates: 1 - Control; 2 - Prebiotic; 3 - Probiotic; 4 - Antibiotic. The variables evaluated were average daily gain (ADG), daily feed intake (DFI), feed conversion (FC) fecal consistency and leukocyte count. At 43 days of age, the animals presented the same weight gain (P> 0.05); however, there was increased intake of the diet containing prebiotic (P> 0.05), and feed conversion was better for control diet (P 0.05), daily feed intake (P> 0.05) and feed conversion (P> 0.05), and also no differences in fecal consistency (P> 0.05). The number of leukocytes increased at 32 days of age when the diets containing prebiotics and probiotics were used (P> 0.05). The diet containing prebiotics increased the number of monocytes (P 0.05), the diets promoted no changes in the immunoglobulins IgA, IgM and IgG (P> 0.05). The use of prebiotics, probiotics and antibiotics did not influence the animals’ performance from 22 to 54 days of age. Keywords : additives; fecal consistency; immunoglobulins; pigs.

Impact of increasing levels of spineless-cactus meal on the ingestive behaviour of grazing steers

&lt;p&gt;The objective of this study was to evaluate the effect of different levels of spineless-cactus meal substituting for maize in diets for supplemented steers grazing on &lt;em&gt;Urochoa brizantha &lt;/em&gt;during the postweaning phase. The experiment was conducted on Princesa do Mateiro farm, located in Ribeirão do Largo-BA, Brazil. Forty crossbred steers with an average body weight of 261 ± 7.46 kg were distributed into four groups for evaluation of the following four levels of substitution of ground maize for spinelesscactus meal: 0.00, 30.00, 60.00, and 90.00%. The results were analysed statistically by variance and regression analyses at a 5% error probability. Increasing the amount of spineless-cactus meal in the diet had a quadratic effect on the grazing time and on the time spent on other activities. The diet had a quadratic effect on the number of grazing periods, the number of periods at the trough, and the total feeding and chewing times. In contrast, the number of periods spent on other activities and on rumination was not influenced by the level of spineless-cactus meal. The bite rate, number of bites per swallow, and number of bites per day increased linearly, whereas the swallowing time and number of cuds ruminated per day decreased as the level of spineless-cactus meal added to the diet wasincreased. The feed and rumination efficiencies of dry matter, neutral detergent fibre, crude protein, and non-fibre carbohydrates were not influenced by the level of substitution of spineless-cactus meal for ground maize. Spinelesscactus meal levels close to 60% probably provided greater fibre degradation, leading the animals to spend more time on social interactions with the group, use the feed better, and possibly have a better feed conversion.&lt;/p&gt;.

Impact of increasing levels of spineless-cactus meal on the ingestive behaviour of grazing steers

The objective of this study was to evaluate the effect of different levels of spineless-cactus meal substituting for maize in diets for supplemented steers grazing on Urochoa brizantha during the postweaning phase. The experiment was conducted on Princesa do Mateiro farm, located in Ribeirão do Largo-BA, Brazil. Forty crossbred steers with an average body weight of 261 ± 7.46 kg were distributed into four groups for evaluation of the following four levels of substitution of ground maize for spinelesscactus meal: 0.00, 30.00, 60.00, and 90.00%. The results were analysed statistically by variance and regression analyses at a 5% error probability. Increasing the amount of spineless-cactus meal in the diet had a quadratic effect on the grazing time and on the time spent on other activities. The diet had a quadratic effect on the number of grazing periods, the number of periods at the trough, and the total feeding and chewing times. In contrast, the number of periods spent on other activities and on rumination was not influenced by the level of spineless-cactus meal. The bite rate, number of bites per swallow, and number of bites per day increased linearly, whereas the swallowing time and number of cuds ruminated per day decreased as the level of spineless-cactus meal added to the diet wasincreased. The feed and rumination efficiencies of dry matter, neutral detergent fibre, crude protein, and non-fibre carbohydrates were not influenced by the level of substitution of spineless-cactus meal for ground maize. Spinelesscactus meal levels close to 60% probably provided greater fibre degradation, leading the animals to spend more time on social interactions with the group, use the feed better, and possibly have a better feed conversion.

USO DE SUCEDÂNEO EM SUBSTITUIÇÃO AO LEITE NO DESEMPENHO DE BEZERROS DA RAÇA HOLANDESA DURANTE A CRIA E RECRIA

Resumo O objetivo deste trabalho foi avaliar a eficiência biológica do sucedâneo em substituição ao leite, na fase de cria e recria de bezerros da raça Holandesa. O trabalho foi realizado na Universidade Tecnológica Federal do Paraná (UTFPR), Dois Vizinhos, entre maio de 2011 e abril de 2012. A pesquisa foi realizada com 32 animais, adotando-se o delineamento inteiramente casualizado com quatro tratamentos e oito repetições: 100% leite; 34% sucedâneo + 66% leite; 66% sucedâneo + 34% leite; e 100% sucedâneo. Os dados foram submetidos à analise de variância e de regressão a 5% de significância. Dentre as medidas morfométricas realizadas, apenas o ganho de perímetro torácico apresentou diferença significativa. A utilização de sucedâneo em substituição ao leite durante a fase de aleitamento apresentou uma resposta linear negativa para os níveis 100%, 66%, 34% sucedâneo, porém durante a fase de recria ocorreu um ganho compensatório dos animais submetidos aos tratamentos 34% e 66% sucedâneo. A utilização de 100% de sucedâneo na alimentação de bezerros holandeses na fase de cria não foi eficiente durante o aleitamento. Durante a fase de recria, a substituição parcial do leite por sucedâneo (66% sucedâneo + 34% leite) mostrou ser a opção mais eficiente, pois apresentou um ganho compensatório favorável.

Pre- and postweaning performance by cows and calves that grazed toxic or nontoxic endophyte-infected tall fescue pastures

Negative effects on cattle grazing tall fescue [Schedonorus arundinaceus (Schreb.) Dumort.] infected with the wild-type endophyte Neotyphodium coenophialum (E+) are well documented, but information about the carryover effects on weaned calves is limited. Our objective was to compare pre- and postweaning performance by spring-calving cows and calves grazing E+ with that by cows grazing a nontoxic endophyte–tall fescue association (NE+). Pregnant Gelbvieh × Angus crossbred cows (n = 136; 492 ± 19.2 kg of initial BW) were stratified by BW and age and allocated randomly to one of four 10-ha pastures in yr 1 (October 15) and one of eight 10-ha pastures in yr 2 (November 30). Pastures were allocated randomly before establishment to E+ or NE+. Cows remained on their assigned pastures until weaning in yr 2 but were removed from NE+ in the summer of yr 1 because of low forage mass. After weaning, calves grazed bermudagrass [Cynodon dactylon (L.) Pers.] followed by cool-season annual grasses. Cow BW and pregnancy rate, and calf weaning weight and preweaning gain were greater (P < 0.05) from NE+ versus E+. Weaning weight differentials were maintained throughout postweaning production phases, resulting in heavier HCW (P < 0.05) by steers and a tendency for greater (P < 0.10) subsequent calving rates by heifers. Therefore, replacing E+ with NE+ may improve preweaning cow and calf performance and heifer reproductive rates, but postweaning gains may not be affected by previous exposure to E+.

Development of piglets raised in a new multi-litter housing system vs. conventional single-litter housing until 9 weeks of age.

This study compared the development until 9 wk of age of piglets raised in either a multi-litter (ML) system or a conventional single-litter (SL) system. The ML system consisted of a multi-suckling system with 5 sows and their litters before weaning, followed by housing in a pen with enrichment in a group of 40 piglets after weaning. In the SL system, piglets were housed with a crated sow before weaning, followed by postweaning housing in groups of 10 littermates in a standard pen. Fifty litters were used in 5 batches and piglets were weaned at 4 wk of age. Preweaning mortality was higher in the ML system than in the SL system (3.22 ± 0.42 vs. 1.52 ± 0.25 piglets per litter, < 0.01), mainly due to crushing before grouping of litters. Litter size at grouping did not differ between systems. ML piglets showed more feed-directed behavior at 2 wk of age (6.80 ± 0.96 vs. 2.35 ± 0.59, < 0.01), suggesting an earlier start of feed exploration, possibly due to social learning from the floor-fed sows and other piglets. Moreover, before weaning, ML piglets showed less damaging oral manipulation (e.g., tail biting) than SL piglets (1.4 ± 0.2 vs. 3.6 ± 0.3 freq/h, < 0.001), which was likely related to the more enriched environment in the ML system. After weaning, ML piglets ate 81% more feed between d 1 and 2 (0.29 ± 0.02 vs. 0.16 ± 0.03 kg/piglet, < 0.01) and had an 82% higher weight gain until d 5 than SL piglets (1.35 ± 0.21 vs. 0.75 ± 0.17 kg, < 0.05) despite a similar weaning weight (ML: 8.4 ± 0.2 kg, SL: 8.3 ± 0.2 kg). Within the first 2 wk after weaning, ML piglets had a lower fecal consistency score (0.27 ± 0.03 vs. 0.39 ± 0.03, < 0.05), indicating a lower occurrence of diarrhea compared with SL piglets. Over the entire 5-wk postweaning phase, ML piglets had a 24% higher weight gain ( < 0.05) and showed more play behavior (4.0 ± 0.3 vs. 2.8 ± 0.3 freq/h, < 0.05) and less damaging oral manipulation (1.8 ± 0.3 vs. 3.5 ± 0.4 freq/h, < 0.01) than SL piglets. These results are probably explained by a combination of the differences in preweaning development, early postweaning performance, and postweaning environment, with a larger and more diverse social group and more physical enrichment in the ML pen. To summarize, provided that preweaning mortality can be reduced, the ML system seems promising for raising robust piglets with better welfare, indicated by a better preweaning behavioral development, improved transition to the postweaning phase, and better postweaning performance.

Intestinal Alkaline Phosphatase: Potential Roles in Promoting Gut Health in Weanling Piglets and Its Modulation by Feed Additives - A Review.

The intestinal environment plays a critical role in maintaining swine health. Many factors such as diet, microbiota, and host intestinal immune response influence the intestinal environment. Intestinal alkaline phosphatase (IAP) is an important apical brush border enzyme that is influenced by these factors. IAP dephosphorylates bacterial lipopolysaccharides (LPS), unmethylated cytosine-guanosine dinucleotides, and flagellin, reducing bacterial toxicity and consequently regulating toll-like receptors (TLRs) activation and inflammation. It also desphosphorylates extracellular nucleotides such as uridine diphosphate and adenosine triphosphate, consequently reducing inflammation, modulating, and preserving the homeostasis of the intestinal microbiota. The apical localization of IAP on the epithelial surface reveals its role on LPS (from luminal bacteria) detoxification. As the expression of IAP is reported to be downregulated in piglets at weaning, LPS from commensal and pathogenic gram-negative bacteria could increase inflammatory processes by TLR-4 activation, increasing diarrhea events during this phase. Although some studies had reported potential IAP roles to promote gut health, investigations about exogenous IAP effects or feed additives modulating IAP expression and activity yet are necessary. However, we discussed in this paper that the critical assessment reported can suggest that exogenous IAP or feed additives that could increase its expression could show beneficial effects to reduce diarrhea events during the post weaning phase. Therefore, the main goals of this review are to discuss IAP’s role in intestinal inflammatory processes and present feed additives used as growth promoters that may modulate IAP expression and activity to promote gut health in piglets.

Effects of calcium soap of rice bran oil fatty acids supplementation alone and with DL-α-tocopherol acetate in lamb diets on performance, digestibility, ruminal parameters and meat quality.

Thirty-six Malpura lambs (28day old and 6.7±0.25kg BW) were distributed equally in three groups having six males and six female. They were adlibitum fed individually three different experimental diets containing calcium soap of fatty acids (CA-FA) at 0 (T1 ) and 40 (T2 and T3 ) g/kg concentrate up to six months of age. Animals in T3 were supplemented additionally with 40mg DL-α-tocopherol acetate/kg of concentrate. The roughage moiety included adlibitum dry Prosopis cineraria and fresh Azadirachata indica leaves. All the lambs were allowed to suckle from their dam up to weaning (90day of age). Supplementation of Ca-FA improved weight gain and feed conversion ratio during both pre- (28-90days) and post-weaning (91-180days) phases; however, no effect of DL-α-tocopherol was observed. Metabolic parameters during post-weaning phase revealed non-significant effect on digestibility but improved nitrogen balance in the test groups. The effect on biochemical attributes did not show any significant alteration in ruminal parameters, blood biochemicals and urinary purine derivatives. Carcass traits revealed higher (p<0.05) dressing yield and loin eye area with Ca-FA supplementation. The value of thiobarbituric reactive substances for nuggets prepared from frozen carcasses revealed significant (p<0.05) reduction in T3 compared to the other dietary groups. Fatty acid profile of adipose tissue revealed higher (p<0.001) 9-octadecanoic, 9-12-octadecadienoic, polyunsaturated fatty acids (PUFA), higher ratio of PUFA/saturated fatty acids (SFA), ω-6/ω-3 and lower SFA in Ca-FA-supplemented groups. It is concluded that supplementation of 40g/kg calcium soap prepared from industrial grade rice bran oil in lamb ration provided additional energy intake, improved N utilization, gain and feed conversion ratio besides improving dressing yield and meat quality with CLA enriched fatty acid profile. DL-α-tocopherol acetate when supplemented at 40mg/kg feed reduced lipid oxidation of meat products thus improving its keeping quality.

Performance of growing cattle on poor-quality rangelands supplemented with farm-formulated protein supplements in Zimbabwe.

Farmers use different non-conventional protein supplements and different feeding strategies to aid their animals survive the dry season in Zimbabwe. The strategies can be giving supplements once a week or once every other day up to very little supplement daily. Supplements are either legume crop residues or forage legumes. However, the efficacy of the use of non-conventional protein supplements in promoting growth and at the same time lowering the age at first calving is little understood. The study tested whether supplementing with farm-formulated non-conventional feeds could reduce live weight loss during the dry season and promote live weight gain as well as early development of sexual maturity in beef cattle. In a completely randomized design, thirty dams with calves on hooves were allocated to five different treatments which were repeated during the dry season for 3 years. The 3-year study results show that weight loss can be controlled, resulting in positive growth in both the pre-weaning and post-weaning phases of growing cattle. Yearlings fed solely on natural pasture lost significant weight during the dry season as compared to supplemented groups. The period to puberty and first calving was achieved at 18 and 27 months, respectively. Using non-conventional protein supplements could thus improve livestock productivity in resource-poor farming communities. It was concluded that smallholder farmers can supplement cattle with a kilogram per day of low-cost farm-based non-conventional legume meal to improve livestock productivity in semi-arid regions of Zimbabwe.

Growth velocity and weaning δ(15)N "Dips" during ontogeny in Macaca mulatta.

A "dip" in the stable nitrogen isotope ratios (δ(15)N) of subadults in the late weaning/early post-weaning phase of growth and development has been observed. Speculatively, this is the mechanism of positive nitrogen balance operating among rapidly growing subadults. An alternate hypothesis for δ(15)N dips is that during weaning, subadults eat lower-(15)N foods than adults. This study explores the role of positive nitrogen balance in affecting δ(15) N variation of growing subadults by comparing growth velocity with stable carbon isotope (δ(13)C) and δ(15)N ratios of blood serum from captive rhesus macaques (Macaca mulatta) (n = 14) with controlled diets during the first 10 months of life. During the first six months, δ(15)N values are inversely correlated with growth in some of the anthropometrics (weight and sagittal circumference). Dips in some infants' δ(15)N values below their mothers' values are observed at the end of the weaning period. However, during this time frame, δ(15)N values of the infants are not correlated with anthropometric indices. Serum stable isotope ratios of lactating and non-lactating adult females differ significantly. Growth in body mass and size explains some of the variation in infant δ(15)N values, but are not responsible for dips in the late weaning/early post-weaning phase. It is advised that future research evaluate the extent to which growth in other body systems affects nitrogen balance and δ(15)N dips during ontogeny, and expand on isotopic differences between lactating and non-lactating females.

Dairy protein in the post-weaning phase is positively associated with BMI and weight up to five years of age

Dairy protein in the post-weaning phase is positively associated with BMI and weight up to five years of age

Low doses of microencapsulated zinc oxide improve performance and modulate the ileum architecture, inflammatory cytokines and tight junctions expression of weaned pigs

The aim of this study was to compare low doses of microencapsulated v. pharmacological ZnO in the diet of piglets on growth performance, ileum health status and architecture. One hundred and forty-four piglets weaned at 28 days and divided in 36 pens (two males and two females per pen), received a basal diet (control, Zn at 50 mg/kg) or the basal diet with ZnO at 3000 mg/kg (pZnO), or with lipid microencapsulated ZnO at 150 or 400 mg/kg (mZnO-300 and mZnO-800, respectively). After 14 and 42 days, three pigs per sex per treatment were euthanized to collect the ileum mucosa for immunohistochemistry, histomorphology, inflammatory cytokines and tight junction components gene expression. Data were analyzed with one-way ANOVA. At 0 to 14 days, the pZnO and mZnO-800 groups had greater average daily gain compared with control (P<0.05). Gain to feed ratio (G:F) in the same time interval was higher in pZnO group compared with control thus resulting in higher BW (P<0.05). At day 14, ileum villi height in mZnO-800 pigs was 343 µm v. 309 and 317 µm in control and pZnO, respectively (P<0.01) and villi:crypts ratio (V:C), as well as cells positive to proliferating cell nuclear antigen (PCNA), were greater in all treated groups compared with control (P<0.01). In mZnO-800 group, interferon-γ mRNA was the lowest (P=0.02), and both pharmacological ZnO and mZnO reduced tumor necrosis factor-α protein level (P<0.0001). Compared with pZnO group, mZnO-800 increased occludin and zonula occludens-1 protein level (1.6-fold and 1.3-fold, respectively; P<0.001). At day 42, both groups receiving microencapsulated ZnO had 1.7 kg greater BW than control and did not differ from pZnO group (P=0.01); ileum villi height and V:C ratio were the greatest for pZnO compared with the other groups, whereas PCNA-positive cells were the most numerous in mZnO-800 group (P<0.001). In conclusion, pigs receiving low doses of microencapsulated ZnO had G:F comparable with those receiving pharmacological level of ZnO in the overall post-weaning phase. Moreover, in the first 2 weeks post-weaning, microencapsulated ZnO effect on inflammatory status and ileum structure and integrity was comparable with pharmacological ZnO.

Traditional and biphasic nonlinear models to describe the growth of goat kids of specialized dairy breeds

The goal of the present study was to evaluate different mathematical models to describe the growth profiles of growing male kids. The kids used in the present study came from two experimental sets: one set of Alpine wethers (castrated at 15 days of age) and another set of Saanen kids. The variables measured in the first set were live weight (W), empty body weight (EBW), carcass weight, organs, empty gastrointestinal tract (GIT), skin, abdominal fat, trimmed cuts, blood, fresh GIT contents, and ruminoreticular fresh, dry matter, neutral detergent fiber, and lignin content at birth and at 15, 90, 135, 210, 270, and 365 days of age. The second set provided W and EBW of Saanen kids measured at 7, 37, 67, 142, and 195 days of age. The models tested were the monomolecular or Brody equation; the Gompertz, Richards, and generalized Michaelis–Menten models of sigmoid growth; and combinations of monomolecular and sigmoid models, forming biphasic models. In addition, four types of variance functions (covariance) were tested, namely, homogeneous, exponential, asymptotic, and power of the mean scaling function for each model. The model selection was based on the Akaike information criterion and its derived likelihood measures. The sigmoid simple models better described the time profiles, and the Gompertz model associated with homogeneous and scaled variances was the best choice for 57.1% of the growth profiles, most likely because of the ill-defined asymptotic phase; the biphasic models presented a lower likelihood probability of support. Nevertheless, the Brody–Gompertz and Brody-exponential growth biphasic models presented reasonable fits to certain variables, such as W, EBW, and carcass from both datasets. Therefore, despite the greater likelihood of the traditional growth functions, the biphasic models are promising for the description of the inflection points observed during the suckling-weaning and post-weaning phases of the goat kids’ growth profiles.

Sainfoin seeds in organic diets for weaned piglets—utilizing the protein-rich grains of a long-known forage legume

AbstractSainfoin (Onobrychis viciifolia) is a tanniniferous legume that has been used as non-bloating forage for horses and ruminants for centuries, but so far its protein-rich seeds have not been utilized as a feedstuff for monogastric animals. In Europe, the main protein sources in diets for organic pigs are the grain legumes faba beans (Vicia faba) and peas (Pisum sativum), alongside the expensive high-quality components soybean cake, skimmed milk powder and potato protein. Because of the scarce supply of organic soybean cake and the highly variable yield of peas, alternative and locally produced protein sources are of great interest. As part of the EU Core Organic II research project ICOPP (improved contribution of local feed to support 100% organic feed supply to pigs and poultry), sainfoin seeds have been tested as a protein source for organic weaned piglets. In a feeding trial, a control diet, one diet containing 10% sainfoin seeds with hulls and two diets with 10 and 16% dehulled seeds, respectively (as fed basis) were fed to 137 piglets (crosses of [Pietrain×Duroc]×[Landrace×Large White]) during the 4-week post-weaning phase. The protein-rich components of the control diet were peas and soybean cake, which were partly substituted for sainfoin seeds in the experimental diets. Sainfoin seeds were found to contain 279 g kg−1 crude protein (388 g kg−1 when dehulled, as fed basis) with an amino acid profile suitable for pig feeding. Neither feed intake and body weight gain nor feed conversion ratio differed between treatments. It is concluded that sainfoin seeds can be a valuable protein source in moderate percentages of 10–16% in organic diets for weaned piglets. Where sainfoin can be cultivated easily and the seeds are harvested, using them as feed for piglets can therefore be recommended.

Effect of hay on performance of Holstein calves at suckling and post-weaning

The objective of this work was to evaluate the performance of Holstein calves in suckling and post-weaning phases, intensively managed during suckling in the absence or presence of hay. Twenty-four male Holstein calves, at an average age of 15 days and initial weight of 43 kg were used in the experiment. The experimental design was completely randomized, consisting of two treatments and six replications. The treatments were as follows: 1) suckling with milk substitute + initial concentrate for calves, ad libitum + temperate grass hay (oat/ryegrass), ad libitum; 2) suckling with milk substitute + initial concentrate for calves, ad libitum. No significant difference was found between treatments for weight gain and feed conversion. However, the supply of hay caused an increase in daily dry matter intake (2.127 vs 1.894 kg). The intake of hay promoted greater stimulus to consumption of concentrate and greater weight at weaning.