Commercial Production Systems Research Articles

Managerial factors affecting milking-abilities of Holstein cattle under intensive production system in Egypt

This article aims to explore milking-ability criteria of Holstein dairy cattle under intensive production system in Egypt and investigate some managerial factors that influence them in dairy farms. The data obtained from five herds belong to a commercial intensive production system farm, Egypt. Data included 3509 records. The values of mean ± SD (CV%) of the milking-ability criteria for Holstein dairy cattle as follow: daily milk yield, kg (dmy), milking duration, min (MD), peak flow rate, kg min−1 (PFR), average flow rate, kg min−1 (AFR), AFR0:15 s of milking, AFR15:30 s of milking, AFR30:60 s of milking, and AFR60:120 s of milking were 30.34 ± 6.76 kg, (22.27%); 4.16 ± 0.79 min (19.06%); 3.62 ± 0.79 (21.77%); 0.28 ± 0.11 (39.48%); 1.40 ± 0.49 (36.37%); 1.26 ± 0.50 (39.95%); and 1.96 ± 0.71 (36.05%), kg min−1, respectively. The milking-time (a.m./p.m.) and the herds’ men influenced significantly (P ≤ 0.01) on dMY, and milking-ability criteria. In addition, there was a significant effect (P˃0.05) of cows’ dry-period on dMY, MD, PFR and AFR. Also, it was clearly appearing that there was a dramatic significant decrease in daily milk yield and AFR by increase mastitis infection times. Milking-ability criteria in Holstien cattle may be go better via good management, hygiene, and well-trained herds’ men. The cubic models are higher in determination coefficient (p ≤ 0.05) than linear models for the curve estimates through the time of lactation period for studied traits. The curve of milk yield and milking-abilities were inconstant all over lactation period.

Optimization of inoculum cell concentration for enhanced lipid production in laboratory-scale cultivation of the marine microalga Chlorella sp. for biofuel applications

Microalgae are considered valuable bioresources due to their ability to produce high lipid content and grow under a variety of environmental conditions, making them strong candidates for sustainable biofuel production. However, the economic feasibility of microalgae-based biofuels depends on optimizing growth conditions in large-scale cultivation systems. This study investigates the effects of varying inoculum cell concentrations on the growth, lipid yield, and fatty acid composition of the locally isolated microalga Chlorella sp. SW5 in 2 L and 5 L cultivation systems. The results indicate that higher inoculum concentrations generally enhance biomass accumulation, with the 2 L system achieving the highest growth rate of 0.42 ± 0.01 day⁻1 at an inoculum concentration of 10⁶ cells/mL. Interestingly, while higher inoculum concentrations reduced lipid production in the 2 L system, the 5 L system showed the highest lipid yield (51.23% ± 4.71% dry weight) at the highest inoculum concentration (10⁷ cells/mL). Despite its moderate growth rate, the 5 L culture with a starting inoculum concentration of 10⁷ cells/mL was selected for fatty acid profiling due to its superior lipid yield and productivity. Gas chromatography-mass spectrometry (GC-MS) analysis revealed that the culture produced a total of 93.18% C14-C18 fatty acids, with a profile dominated by saturated (56.33%) and monounsaturated (16.85%) fatty acids, which are essential for biodiesel quality. These findings provide valuable insights into the potential for scaling up microalgal systems for commercial biofuel production, highlighting strategies to optimize productivity.

Effect of dietary supplementation with oregano oil premix on the antioxidant status, performance, and meat quality in slow-growth broiler chickens

This study investigated the influence of dietary supplementation with oregano oil premix on the antioxidant status, performance, and meat quality of slow-growth genotype chickens raised under a commercial production system. The study included two groups, with nine replicates: Group A) 54.000 broilers raised in free-range farms and fed the basal diet, and Group B) 27.000 broilers raised in free-range farms and fed the basal diet supplemented with oregano oil premix. Oregano oil was blended with a standard premix (120 g/ton), which was then mixed with the feed (amount adjusted on the growth stage). The results showed that serum total antioxidant capacity (TAC) was significantly higher (p ≤ 0.05) in the non-supplemented group compared to the dietary-supplemented group with oregano oil premix. In contrast, thigh muscle total antioxidant capacity was significantly increased in the supplemented group compared to the non-supplemented group (p ≤ 0.05). There were no differences in serum and thigh muscle Thiobarbituric Acid Reactive Substances (TBARS) and performance parameters between the two groups. Chickens fed with the oregano oil premix exhibited increased protein and ash content, pH value, and higher smell, taste, and colour scores compared to the non-supplemented group. Summarising, our large-scale in field study showed that incorporating oregano oil premix in slow-growth and free-range chickens’ diet improves the thigh muscle total antioxidant capacity and meat quality. The results indicate that the oregano oil premix positively impacts the nutritional value of the final product. However, more research is needed under in field conditions to draw a safer conclusion.

Alternative and Emerging Mulch Technologies for Organic and Sustainable Agriculture in the United States: A Review

Plastic mulches made from nonbiodegradable polymers (e.g., polyethylene) provide an essential service in commercial horticultural production systems by enhancing crop productivity through weed suppression, soil moisture conservation, and moderating soil and canopy temperature conditions. Plastic mulches are particularly important in organic agriculture because weed management options are limited. Nevertheless, there is increasing concern about addressing the negative environmental impacts of plastic mulch waste. Soil-biodegradable plastic mulch (BDM) films that are designed to biodegrade in soils after incorporation are promising alternatives to nonbiodegradable plastic mulch. However, although the US organic standards technically permit the use of BDM films, no commercially available products meet National Organic Program (NOP) requirements for 100% biobased content and 90% degradation after 2 years following soil incorporation (7 Code of Federal Regulations, section 205.2). Other concerns about biodegradable film mulches include high perceived cost, esthetics, and uncertainties regarding the impacts of soil incorporation. New mulch technologies have emerged to diversify sustainable mulch options and overcome barriers associated with BDM film use in organic production. The objective of this study was to provide an overview of alternative and emerging mulch technologies, with an emphasis on biodegradable mulches, including water-based sprayable mulches such as hydromulch and foam mulch, and biobased agrotextiles. Information about how these mulch technologies contribute to organic and sustainable agriculture is provided, along with definitions, opportunities, challenges, and recommended areas for future research.

Financial impact of low pathogenic avian influenza virus subtype H9N2 on commercial broiler chicken and egg layer production systems in Pakistan

Low Pathogenic Avian Influenza (LPAI) subtype H9N2 is endemic in Pakistan and impacts poultry farming through disease related mortality, poor weight gain and reduced egg production. This study aims to estimate the farm-level financial impact of LPAI H9N2 infection on commercial broiler and layer production systems in Pakistan.A questionnaire based cross-sectional survey of 138 broiler farms and 136 layer farms in Pakistan was conducted in 2019. Primary data collected by cross-sectional survey along with expert opinion and published literature were used to parameterize five stochastic production and gross margin models for three broiler and two layer production systems: fully integrated production (FIP), partially integrated production (PIP) and independent farming production (IP) systems. Partial budget analysis were then carried out to estimate the financial impact of LPAI H9N2.Results indicate that in broiler production systems, starting with 35,000 day old chicks (DOC) per batch, the net cost of disease (million PKR/production cycle) was estimated at 4.10 (14,862 USD), 4.62 (16,747 USD) and 2.46 (8917 USD) for IP, PIP and FIP systems, respectively. The disease produced a negative gross margin (defined here as revenue minus replacement and variable costs) in IP (-53 PKR (-0.19 USD)/DOC bought) and PI (-25 PKR (-0.091 USD)/DOC bought) systems, while remained positive for FIP systems (87 PKR (0.32 USD)/DOC bought). For layer production systems, (mean flock size as 48,000 DOCs) the net cost (million PKR/production cycle) was 29.75 (107,095.21 USD) and 29.51 (106,223.45 USD) IP and PIP systems, respectively, and produced negative gross margin in both systems.The outcomes of the study highlight the vulnerability of independent and partially integrated production systems to the disease. These findings also offer a decision-making tool to the farmers and policy makers to evaluate avian influenza surveillance systems and control interventions in Pakistan.

A Review of Swine Breeding Herd Biosecurity in the United States to Prevent Virus Entry Using Porcine Reproductive and Respiratory Syndrome Virus as a Model Pathogen.

The prevention of disease introduction into swine herds requires the practice of science-based protocols of biosecurity that have been validated to reduce the risk of the entry of targeted pathogens. The fundamental pillars of biosecurity include bio-exclusion, biocontainment, and bio-management. Biosecurity protocols must be science-based, a way of life, continuously validated, cost-effective, and benchmarked over time. This paper will review these concepts, the direct and indirect routes of transmission of porcine reproductive and respiratory syndrome virus (PRRSV), and the interventions that have been designed and validated to prevent infection of the breeding herd. It will close with a review of Next Generation Biosecurity, describing how a science-based approach is being used to prevent PRRSV infection in breeding herds from a large commercial pork production system in the US.

Shedding the Light on Powdery Mildew: The Use of Optical Irradiation in Management of the Disease.

Ultraviolet (UV) irradiation below 300 nm may control powdery mildew in numerous crops. Depending on disease pressure, wavelength, and crop growth stage, one to three applications of 100-200 J/m2 per week at night are as effective or better than the best fungicides. Higher doses may harm the plants and reduce yields. Although red light alone or in combination with UV has a suppressive effect on powdery mildew, concomitant or subsequent exposure to blue light or UV-A strongly reduces the efficacy of UV treatments. To be effective, direct exposure of the pathogen/infection sites to UV/red light is important, but there are clear indications for the involvement of induced resistance in the host. Other pathogens and pests are susceptible to UV, but the effective dose may be phytotoxic. Although there are certain limitations, this technology is gradually becoming more used in both protected and open-field commercial production systems.

421 An evaluation of Spanish-speaking animal caretakers attitudes towards piglet euthanasia in a large commercial swine production system in Southwestern U.S

421 An evaluation of Spanish-speaking animal caretakers attitudes towards piglet euthanasia in a large commercial swine production system in Southwestern U.S

Fluoroquinolone-resistant Campylobacter in backyard and commercial broiler production systems in the United States.

Campylobacter spp. are one of the leading foodborne pathogens in the world, and chickens are a known reservoir. This is significant considering broiler chicken is the top consumed meat worldwide. In the USA, backyard poultry production is increasing, but little research has been done to investigate prevalence and antimicrobial resistance associated with Campylobacter in these environments. Our study encompasses a farm-to-genome approach to identify Campylobacter and investigate its antimicrobial resistance phenotypically and genotypically. We travelled to 10 backyard and 10 integrated commercial broiler farms to follow a flock throughout production. We sampled at days 10, 31 and 52 for backyard and 10, 24 and 38 for commercial farms. Bird faecal (n = 10) and various environmental samples (soil n = 5, litter/compost n = 5, and feeder and waterer swabs n = 6) were collected at each visit and processed for Campylobacter. Our results show a higher prevalence of Campylobacter in samples from backyard farms (21.9%) compared to commercial (12.2%). Most of our isolates were identified as C. jejuni (70.8%) and the remainder as C. coli (29.2%). Antimicrobial susceptibility testing reveals phenotypic resistance to ciprofloxacin (40.2%), an important treatment drug for Campylobacter infection, and tetracycline (46.6%). A higher proportion of resistance was found in C. jejuni isolates and commercial farms. Whole-genome sequencing revealed resistance genes, such as tet(O) and gyrA_T86I point mutation, that may confer resistance. Overall, our research emphasizes the need for interventions to curb prevalence of resistant Campylobacter spp. on broiler production systems.

Factors associated with the productive longevity of sows in commercial breeding herds

Abstract. Maximizing sows' productive longevity (PL) represents a significant challenge faced by the swine industry, as the growing increase in the removal rate of sows, mainly young sows, directly impacts the system's economy. In addition, there are ethical concerns associated with animal welfare issues due to the low PL of sows. The objective of this study was to identify and evaluate the risk factors influencing the removal of sows from commercial swine production systems. The variable of interest was the PL of sows. The PL was modeled using Cox regression analysis to identify the factors that affected this variable. The factor with the greatest contribution to PL was sow type (ST), followed by the return to estrus percentage (REP), herd size (HS), season, lactation duration, weaning–estrus interval (WEI), piglets born alive, mummy percentage, and total piglets born. The removal risk was higher for hyperprolific sows than for normal sows. According to the nonproductive day (NPD) variable (an indicator that considers REP and WEI in its calculation), sows with more than 60 nonproductive days per year are at higher risk of elimination. The risk of removal was higher for sows from large herds than for sows from medium or small herds. The PL of sows within a herd is determined by the type of sow and the sows' association with environmental disturbances, including climatic factors (artificial climate control), management practices (human resources), and economic resources (size and infrastructure).

Assessing lameness prevalence and associated risk factors in crossbred dairy cows across diverse management environments

BackgroundA thorough understanding of lameness prevalence is essential for evaluating the impact of this condition on the dairy industry and assessing the effectiveness of preventive strategies designed to minimize its occurrence. Therefore, this cross-sectional study aimed to ascertain the prevalence of lameness and identify potential risk factors associated with lameness in Holstein Friesian crossbred cows across both commercial and smallholder dairy production systems in Bengaluru Rural District of Karnataka, India.MethodsThe research encompassed six commercial dairy farms and 139 smallholder dairy farms, involving a total of 617 Holstein Friesian crossbred cattle. On-site surveys were conducted at the farms, employing a meticulously designed questionnaire. Lameness in dairy cattle was assessed subjectively using a locomotion scoring system. Both bivariate and binary logistic regression models were employed for risk assessment, while principal components analysis (PCA) was conducted to address the high dimensionality of the data and capture the underlying structure of the explanatory variables.ResultsThe overall lameness prevalence of 21.9% in commercial dairy farms and 4.6% in smallholder dairy farms. Various factors such as age, body weight, parity, body condition score (BCS), floor type, hock and knee injuries, animal hygiene, provision of hoof trimming, and the presence of hoof lesions were found to be significantly associated with lameness. Binary logistic regression analysis indicated that the odds of lameness in crossbred cows increased with higher parity, decreased BCS, presence of hard flooring, poor animal hygiene, and the existence of hoof lesions. These factors were identified as potential risk factors for lameness in dairy cows. Principal component analysis unveiled five components explaining 71.32% of the total variance in commercial farms and 61.21% in smallholder dairy farms. The extracted components demonstrated higher loadings of housing and management factors (such as hoof trimming and provision of footbath) and animal-level factors (including parity, age, and BCS) in relation to lameness in dairy cows.ConclusionsThe findings suggest that principal component analysis effectively reduces the dimensionality of risk factors. Addressing these identified risk factors for lameness is crucial for the strategic management of lameness in dairy cows. Future research in India should investigate the effectiveness of management interventions targeted at the identified risk factors in preventing lameness in dairy cattle across diverse environments.

Epidemiology and Risk Factors of Infectious Bursal Disease: A Review

Infectious Bursal Disease (IBD) has been a great challenge to the poultry industry world-wide for a long time and has a major setback to productivity and profitability in the poultry industries of developing nations including Ethiopia. In Ethiopia IBDV was spread to almost all the regions and agro-ecological zones and a recent country wide study reported IBDV seropositivity rates in backyard chickens to be close to 95.7%. The infectious bursal disease is widespread viral diseases that affect chicken kept in commercial and backyard production system. Infectious bursal disease virus is a primary affect bursa fabricius of young chicks at the age of 3 to 6 weeks. The most common mode of infection is through the oral route, but conjunctiva and respiratory routes may also be involved. The infectious bursal disease is host-specific and extremely contagious. Age, breed, degree of passive immunity, the virulence of the strain of the virus, biosecurity, and secondary infections associated with the immunosuppressive effects are the most affecting risk factors of this disease worldwide. Although, many studies have been done as world and in Ethiopia concerning the prevalence and identifying predisposing factors of this disease, further experiment on developing vaccines of specific strains and implementation of prevention and control program are needed to be emphasized.

Assessment of Welfare Problems in Broilers: Focus on Musculoskeletal Problems Associated with Their Rapid Growth.

The growth of the broiler industry has been accompanied with concerns over the environmental and social impacts on intensive production systems, as well as the welfare of the animals themselves. As a result, since the 2000s, there has been growing interest in alternative production systems that improve animal welfare and sustainability. In this context, it is important to prioritize the welfare of broilers in commercial production systems and to use reliable welfare indicators to provide consumers with information about the welfare of the animals they consume. Resource-based measures (RBM) are based on assessing the resources available to the birds in terms of their housing, environment, and management practices, such as stocking density, litter quality, lighting and air quality, etc. Outcome-based measures (OBM), also known as animal-based measures, focus on assessing the actual welfare outcomes for the birds, such as footpad dermatitis, hock burn, contamination or damage to feathers, gait score, mortality, etc. These OBM-based measures are one of the more direct indicators of welfare and can help identify any welfare issues. The present review highlighted the factors that affect animal welfare indicators focused on OBMs which can be used in the commercial broiler farms.

Milk replacer feeding once or twice a day did not change the ruminal metabolomic profile and the microbial diversity of dairy calves from birth to weaning

In commercial dairy production systems, feeding calves once a day could be an alternative to reduce labor expenses. Several studies comparing once (OAD) versus twice (TAD) a day milk feeding systems have not evidenced differences in calf growth, rumen development, blood parameters or health scores, but impact on ruminal microbiota remains to be investigated. The objective of this study was to determine the effects of OAD or TAD on the establishment of the ruminal microbiota and its metabolic activity. Sixteen male calves (45.9 ± 5.7 kg at birth) were involved in the trial from birth to weaning (63 d). After the colostrum phase, 2 feeding programs based on a milk replacer were tested and calves were allocated to these programs on d 5. To study the establishment of the bacterial community, ruminal fluid was obtained from each calf one hour after the morning meal at 7 (d 7), 35 (d 35) and 63 (d 63) days of age. The ruminal metabolome was evaluated at a 7 d interval from d 1 to d 63. Ruminal microbiota and metabolite profiles were characterized by 16 S rRNA gene sequencing- and by H-NMR spectroscopy, respectively. Our results showed that feeding milk replacer once or twice a day did not change the ruminal microbiota and metabolites of dairy calves from birth to weaning. Microbial data showed that diversity and richness increased with age, suggesting a shift from an heterogeneous and less diverse community after birth (d 7) to a more diverse but homogeneous community at 35 and 63 d. These findings suggest that feeding milk once a day can be successfully applied to a calf feeding system without compromising microbial establishment and functions.

Serotypes Diversity, Virulence, and Antimicrobial Resistance of Non-Typhoidal Salmonella Isolates in Commercial and Backyard Egg Production Systems in Egypt

Serotypes Diversity, Virulence, and Antimicrobial Resistance of Non-Typhoidal Salmonella Isolates in Commercial and Backyard Egg Production Systems in Egypt

Bull sperm cryopreservation: An overview on the current status and future perspectives

Cryopreservation refers to freezing cells or tissues at extremely low temperatures, allowing them to be stored for extended periods while maintaining viability. Cryopreserved bull semen has become an essential tool in cattle breeding programs and commercial cattle production systems. This review provides a detailed analysis of the current methods and challenges in preserving bull sperm using cryopreservation. We explore the effects of cryopreservation on sperm cells, the role of different cryoprotectants, as well as the progress made in the analysis of bull semen. It also highlights the impact of the freezing process on sperm morphology and functionality, emphasizing the importance of optimizing cryopreservation techniques to maintain sperm fertility and viability. The article underscores the significance of cryopreservation technology in cattle genetics and breeding and suggests future research to enhance cryopreservation techniques.

Field efficacy of botanicals and beneficial microbes to control banana mealybug (Pseudococcus elisae Borchsenius) (Hemiptera: Pseudococcidae)

The banana mealybug (Pseudococcus elisae Borchsenius) causes significant economic losses to banana production. Prior to the 2019 ban of the organophosphate chlorpyrifos use in commercial banana production systems due to high chlorpyrifos residue levels on banana fruits, chlorpyrifos-treated exclusion bags were commonly used to mitigate mealybug infestation on banana bunches and fingers. Short- and long-term effects of 2 beneficial microbes (Beauveria bassiana and Kosakonia radicincitans), 2 neem-based botanicals (Orgamix and Rata®), 3 chemical insecticides Pyriforce® (Chlorpyriphos-ethyl), Calixine Super® (Acetamipride and Bifenthrin), and Parastar EC40® (Imidachlorpride and Lambda-cyhalothrin), and tap water (Control) were evaluated on mealybug in a newly established and 5-year-old banana farms. Mealybug sampling was conducted for three months after each insecticide application and their population dynamics was calculated using Mann-Kendall trend statistics (S). For the 5-year-old banana farm, except the control, all treatments caused significant (P < 0.05) short-term reduction in mealybug population from pre-treatment application to 5 days in March, July and November samplings. Mealybug population reduction in March was greater than 90% for Calixine Super®, Orgamix and Beauveria, and between 80% and 90% for Kosakonia, Rata and Parastar EC40® (P < 0.05). A similar trend was recorded in July and November, with a higher reduction for Beauveria (52.08%) in July. An increasing linear mealybug trend was observed between March and June (S was positive, P > 0.05) across all treatments, while Orgamix and Rata® caused downward trend between July and October. A downward mealybug trend occurred for Parastar EC40® (S = −1), Rata® (S = −3), Beauveria (S = −6) and Kosakonia (S = −3) between November and January. Biorationals effectively reduced mealybug populations better than chlorpyrifos, while beneficial microbes and neem-based botanicals demonstrated long-term potency on mealybug.

Development of an accelerator-based neutron source to prototype Mo-99 production, Part II: A liquid LBE loop under a high vacuum

To provide US domestic supply of Mo-99 without using high-enriched uranium (HEU), a subcritical uranium target assembly (UTA) is irradiated by an accelerator-based neutron source to create Mo-99 through fission. Part I of this work discusses the design of a liquid lead–bismuth eutectic (LBE) windowless target for an accelerator-based neutron source development. Part II discusses how to couple this windowless target to an accelerator operating at an ultra-high vacuum and the subcritical UTA cooled by water at room temperature.Due to the windowless design of the target, the liquid LBE flow shares an ultra-high vacuum (<1.3 × 10−7 Pa or 10−9 Torr) space with the accelerator. As a result of this shared vacuum space, the LBE system must operate at a high vacuum (10−3 ∼ 10−6 Pa or 10−5 ∼ 10−8 Torr). A magnetic rotary motion feedthrough unit utilizes magnetic fluid to allow rotation of the pump while maintaining a high vacuum environment. Prior to testing the LBE system under vacuum, a pump curve measurement is performed to estimate flowrate in the system. This measurement also generates data on orifice loss coefficients, which are compared to correlations in literature. The second experiment investigates vacuum level in the LBE system during operation. High vacuum is maintained (10−3 ∼ 10−5 Pa or 10−5 ∼ 10−7 Torr) during system operation, and a residual gas analyzer (RGA) scan shows that partial pressures of residual gases in the LBE system lower over the duration of LBE system operations. The third experiment investigates the gravity driven liquid LBE flowing out of the target chamber in the return line, which is partially full. If the liquid LBE is not drained quickly enough, flooding in the target chamber could occur. The coefficient n in the Manning equation is found to be around 0.008 s/m1/3. The last experiment performed is a demonstration that a vacuum jacket could provide sufficient thermal insulation to allow coupling between 300 °C LBE loop and a water tank at room temperature. The results from these experiments have influenced the development of the neutron source for the future commercial scale Mo-99 production system.

114 Effects of Zinc Supplementation in Gestating Sow Diets on Growth Performance of the Progeny from Birth to Market Reared Under Commercial Conditions

Abstract The objective of this study was to evaluate the effects of different Zn supplementation strategies for gestating sows on growth performance of the progeny from birth to market. Pregnant sows (n = 417) were assigned to 1 of 3 dietary treatments in a randomized complete block design based on parity and body condition. Dietary treatments consisted of: 1) Control (CON), corn- soybean meal-based diet with 125 ppm of Zn/kg diet supplied by ZnO (standard basal diet), for a total daily intake of 250 ppm Zn; 2) Partial Supplementation (PS), CON diet + 625 ppm supplemental Zn top-dressed for a total daily intake of 850 ppm Zn provided from d 80 of gestation up to farrowing; and 3) Total Supplementation (TS), CON diet + 625 ppm supplemental Zn top-dressed for a total daily intake of 850 ppm Zn provided throughout the entire gestation phase. Individual body weight was recorded for all piglets at birth (n = 6,349) and at weaning (n = 5,016). A subgroup of piglets (same gender, housed in same farm) was also individually weighed at the end of nursery phase (n = 1207) and at the end of finishing phase (n = 260). Data were assessed by analysis of variance interpreted at 5 and 10% probability levels, adjusted by the Tukey-Kramer test for multiple comparisons. Piglets born from sows whose diets were supplemented with Zn throughout the entire gestational period (TS) tended (P = 0.10) to be heavier at birth compared with piglets born from CON sows (Table 1). The offspring from TS sows tended (P = 0.09) to have greater average daily weight gains during lactation and were heavier (P = 0.04) at weaning compared with the offspring from CON sows, with the offspring from PS sows being intermediate. Although there was no evidence for differences in nursery average daily weight gain, piglets from TS sows tended (P = 0.10) to be heavier at the end of the nursery compared with piglets from CON sows, with piglets from PS intermediate. Pigs from TS sows had greater (P = 0.003) average daily weight gain during the finishing phase and were heavier (P = 0.03) at slaughter. Only animals from the treatments CON and TS were evaluated at the end of the trial because no evidence for differences (P &amp;gt; 0.10) between CON and PS were found at the end of the nursery phase. In conclusion, Zn supplementation in gestating sow diet fed throughout the entire gestation period optimized the performance of the progeny from birth to market and should be considered as a viable prenatal intervention in commercial production systems.

128 Lysine Titration for Intact Males and Gilts During the Grower-Finisher Period in Both Summer and Winter Seasons in a South African Commercial Production System

Abstract The decision as to the optimum amount of dietary balanced protein to feed to commercial grower-finisher pigs should be based on both biology and economics. Terminal sired genotypes are constantly changing due to the selection pressures applied by geneticists on the patrilineal as well as matrilineal animals, as are the relative costs of protein-containing ingredients and the revenue derived from the sale of pork. Thus, the objective of this study was to determine the most efficacy and economical levels of lysine to feed grower finisher swine in both the summer and winter seasons in South Africa. The trial was conducted at the Baynesfield Swine Research Unit at Baynsefield Estate in KwaZulu Natal, South Africa. A total of 528 animals (26.48 ± 0.33 kg initial BW, TN 70 Topig genetics, 70-d of age) were used in an 84-day study, consisting of the grower-finisher period. The house consists of 48 pens each containing 11 pigs with a total of 528 pigs in the house. Pens were randomly allocated to one of six treatments (n = 8 pens). Each diet by phase was formulated with the same NE but with different SID Lys levels (120%, 110%, 100%, 90%, 80%, 70%) of the Topigs Norsvin Tempo Progeny Grower feed manual. All the diets were fed in a four-phase program. Individual body weight and pen feed intake were taken at each phase change. Data was analyzed utilizing Prox MIX (SAS, 2021). Pigs had ad libitum access to feed and water. Feed intake and body eight were measured at every phase change. Additionally, the carcass variables of percent lean, grade, cold carcass weight, and yield were measured at slaughter. The economic variables of feed cost, carcass value, mofc, and cost per gain were calculated to make a comparison. Statistical analysis was conducted in SAS (2021) utilizing the Proc GLM model for the average effects within each period and connection letter calculated with Fisher’s test. Yield and grade were optimized when pigs were fed the 100% SID Lysine diet. Pigs fed the 120% SID Lysine diet had the best overall gain and slaughter BW in both seasons (Table 1). Pigs that were fed the 120% SID Lys diet had the greatest average daily gain when compared with other treatments for the winter trial but during the summer trial the pigs that were fed the 100% SID Lys diets showed the greatest average daily gain. However, the greatest margin over feed cost during both summer and winter was obtained from the 90% SID lysine treatment. In conclusion, raw ingredient costs and seasonality are critical components when optimizing SID lysine for more than just gain but profitability.