Cattle Growth Research Articles

PSXIV-10 Estimation of Genetic Parameters of Traits Associated with Water Efficiency, Feed Efficiency and Growth in Beef Cattle

Abstract Concerns about water availability, quality and accessibility have intensified. The livestock industry, particularly the beef sector, is under pressure to adopt more sustainable practices that optimize water usage while improving growth and feed efficiency. The objective of this study was to estimate the genetic parameters of traits associated with water efficiency, feed efficiency and growth in beef cattle. The data were collected from 916 seedstock bulls and heifers representing six breeds (Angus, Charolais, Hereford, Limousin, Simmental and Sim-Angus) in a facility equipped with Vytelle SENSE feed intake, water intake and in-pen body weight recording systems, located at the West Virginia University central testing facility in Wardensville, WV. The animals were part of six performance tests between November 2019 and September 2022, with an average age at the start of the test of 284 days, and an average test duration of 73 days. The rations were formulated to achieve 1.5 to 1.6 kg/d ADG (depending on the test) and had a high forage inclusion (>75% corn silage and >15% dry hay, as fed). The facility consists of 5 pens and animals were rotated every two weeks through the pens, so all animals are exposed to all pens. The phenotypes analyzed were average daily water intake (DWI), residual water intake (RWI), average daily dry matter intake (DMI), residual feed intake (RFI), and average daily gain (ADG). RWI and RFI were used to measure the water and feed efficiency of the animals. The genetic parameters were estimated with multi-trait animal models using Echidna mixed model software. In all models, breed, sex and the contemporary group (trial number and pen group) were included as fixed effects, the age at the start of the test was added as a covariate, and the animal was treated as a random effect. RWI and RFI were analyzed by adding ADG and metabolic mid-weight as additional covariates. The estimates of heritability for DWI, RWI, DMI, RFI and ADG were 0.49 (± 0.11), 0.40 (± 0.10), 0.35 (± 0.11), 0.16 (± 0.07) and 0.47 (± 0.11) respectively. Average daily water intake exhibited a positive genetic correlation with RWI (0.90), DMI (0.71), and ADG (0.76). On the other hand, the genetic correlation between RWI and RFI was not significantly different from zero, and genetic correlation between RWI and ADG was slightly positive. These results suggest that selecting for enhanced water efficiency in beef cattle can effectively decrease the daily water consumption without any adverse effect on feed efficiency, although it may have a small impact on growth. The complete genetic and phenotypic correlations are in Table 1. In conclusion, the traits associated with water intake and efficiency in beef cattle have a sizable genetic component and show potential for genetic improvement.

422 Mineral Content of Invaded Grassland Forages Is Affected By Precipitation and Management

Abstract Mineral content of grazed forage influences overall health, growth and reproduction of cattle and promotes maximum cattle productivity. However, grassland mineral content may not always meet cattle requirements throughout the grazing season and can be affected by precipitation of the season. Most of the Northern Great Plains grassland is invaded by exotic perennial grass species that have a uniform growth habit and response to precipitation. Growth habitat can be controlled by grazing or mowing, which may alter mineral content. No studies have examined the combined effects of mowing and drought on forage mineral concentration of invaded grassland. Therefore, the objective of this study was to determine mineral concentration of forage in rangeland pastures in seasons of low compared with normal precipitation and mowing status and model recommendations for mitigating low mineral content. This study was conducted at the Northern Great Plains Research Laboratory in Mandan, North Dakota USA. Pastures were sampled across several years and pasture locations, with enclosed plots mowed or not mowed in April, to simulate early season mobgrazing or clipping. Quarter- meter quadrats were taken every two weeks of the grazing seasons from plots in each pasture, one year dry and the other normal. Samples were analyzed for macrominerals and trace minerals via ICP-aa spectroscopy. Forage mineral content was analyzed as a completely randomized design using the MIXED procedure of SAS (SAS 9.4, Cary, NC). Total ash content was different by year (P = 0.0053) but not affected by mowing (P = 0.21). Potassium and phosphorus were not different due to mowing, nor effected by precipitation. Calcium was affected by mowing (P = 0.0065) and tended be affected by precipitation (P = 0.11). Zinc, copper, molybdenum, manganese and iron were all found to be significantly affected by precipitation (P < 0.001). When applied to a beef nutrient requirement model, Ca and P were generally adequate to meet recommended amounts for lactating cows based on a May-calving 1,200-pound cow most months of the season but did not meet needs of a 1400 lb. cow and calf. Forage phosphorus content was significantly less in June of each year, but adequate the rest of the season, suggesting targeting phosphorus supplementation for only the least months would save on mineral costs. Understanding forage mineral fluctuations across the grazing season may provide producers with tools to make the best supplementation strategies and use the most appropriate mineral formulations to maximize performance and reduce input cost.

PSVI-5 Optimizing Limited Deep Phenotyping Capacity for Genetic Studies and Routine Genetic Evaluations: Application to Boar Taint

Abstract In the context of genetic research, but even more for routine genetic evaluations, a recurrent problem is the difficulty to obtain measurements for certain required phenotypes. This can be caused by limited facilities, difficulties in sampling, expensive analyses, limited staff relative to number of animals, and many other reasons. It may therefore be necessary to select which animals to phenotype while maintaining the phenotyping quality and avoiding bias or omitting some animals of interest. This implies developing strategies to do the phenotyping in a non-biased way using a priori available minimum knowledge. An example could be predicting post weaning growth of cattle based on earlier information as birth weight and weaning weight to optimize the use of feed intake or methane measurement facilities. In pigs, similar situations might occur for growth or emissions. However, another important example is boar taint (BT) which shows that not only sequential weighing, but also partial measurements of BT may require attention. BT is defined as urinary and fecal and associated with 2 major compounds, androstenone (AND) and skatole (SKA). The classical method of odor discrimination, “Human Nose Score” (HNS), is notoriously unreliable. Even if odor is known to be complex, adding AND and SKA to HNS would help reveal better the boar taint condition (i.e., phenotype). However, the measurements of AND and SKA or other compounds in fat are expensive. Therefore, it would be important to optimize these measurements by selecting relevant fat samples taken at slaughterhouses. We tested the following optimization strategy. The objective was to obtain a good distribution of a posteriori measured AND and SKA in the selected samples given initial asymmetric populations with positive HNS (3 to 10% declared positives). In a first step, the strategy pooled 2 available HNS for 997 across 22 contemporary groups (CG) and added limited chemical measurements (218/997) available for older samples. The data were obtained from a boar progeny testing scheme; therefore, CG were linked through connecting sires from artificial insemination having sons in different CG. A multi-trait BLUP model was used adjusting for metabolic weight using a 4-generation pedigree. A total of 15% of the animals in the last 6 contemporary groups were selected using first positive HNS (17/300), then keeping the highest and lowest predictions and maintaining diversity by not repeating boars from the same sire-family (i.e., when a family was already present, the next animal was taken). A posteriori chemical analyses were performed on selected samples to compare predicted and observed classifications in tainted and untainted. Research showed an accuracy of 0.73 (Table 1), leading to 58% tainted and 42% untainted compared with the expected ratio. Improvements of this strategy are currently in development, including using genomics.

PSI-3 Effects of Strategic Blending of Food Industry By-Products with Canola Meal on in Vitro and in Situ Fermentation and Nutrient Degradation

Abstract Canola meal (CM) has become an increasingly available high protein feed source for beef cattle in North America, thanks to the expansion of the canola crushing industry in Western Canada and the United States. The inclusion of CM in diets has been reported to improve nutrient utilization and the performance of growing beef cattle. However, the energy value of CM was not as high as barley grain finishing diets, resulting in poorer performance of finishing feedlot steers. Pea starch and pea molasses are available as food industry by-products of industrial pea protein extraction. However, the utilization of these food industry by-products as a component of livestock feed has not been well evaluated. The strategic blending of food industry by-products, such as pea starch and pea molasses, with canola meal (CM) is a novel approach to improving the energy density of CM as animal feed. Nutrient synchrony, where the energy and protein availability in the rumen is synchronized to maximize the ruminal microbial fermentation, has been proposed to improve animal performance. The objectives of our study were to evaluate the in vitro and in situ fermentation and nutrient degradability of novel blended CM. Pea starch and pea molasses were added at 5% (CM5) and 10% (CM10) levels in CM (DM basis), with regular CM serving as control (CON). The in vitro study consisted of two runs of 24 h incubations with three replicates per treatment. The in situ study utilized three cannulated beef heifers and used the same number of replicates of samples and time periods as for the in vitro study. Results indicated a numerical improvement in DM degradation for CM5 and CM10 than CON both in vitro and in situ incubations. Total gas production (mmol) was numerically greater, while the proportion of methane (mmol and g/DM) was less for CM5 than CON. Results indicated that in vitro fermentation of CM5 was enhanced, while greater propionate production from CM5 likely reduced methane production. Further evaluation of these food industry by-products for beef cattle growth performance studies could provide valuable information about rumen fermentation, nutrient digestibility, and energy value of these novel blended CM.

PSVI-28 The Effects Supplementing Tannin Blend on Growth Performance, Energetic Efficiency, and Carcass Characteristics of Calf-Fed Steers

Abstract Objective of the current study was to evaluate the effects of tannin supplementation on cattle growth performance, energetic efficiency, and carcass characteristics of calf-fed steers. One hundred and sixty dairy steer calves with initial body weight (IBW) of 129.85 ± 3 kg, were blocked by IBW and randomly assigned to 40 pens (4 steers/pen; 10 pens per dietary treatment). Dietary treatments were: 1) Control (no additives); 2) MON (30 mg/kg monensin); 3) TAN (15 g/kg ByPRO; 70% condensed tannin; Silvateam USA, Tontitown, AR); and 4) MON+TAN (30 mg/kg monensin + 15 g/kg ByPRO). All steers were fed a similar steam-flaked corn-based diet (63.5% steam-flaked corn, 12.0% hay, 17.5% of dry distillers grains with solubles, 4.0% cane molasses, and 3.0% vitamin/mineral supplement). All cattle were slaughtered after 328 days of feed. There were no effects (P ≥ 0.13) of dietary treatment on final BW (615 ± 22 kg), overall average daily gain (1.48 ± 0.07 kg/day), overall dry matter intake (7.93 ± 0.39 kg/day), overall gain to feed ratio (0.187 ± 0.07), and overall observed vs. expected net energy for maintenance and gain (1.00 ± 0.03 and 1.00 ± 0.04, respectively). However, cattle receiving MON or MON+TAN supplementation increased (P ≤ 0.04) BW and gain to feed ratio in the first 112 days on feed compared with cattle in the control treatment. Moreover, cattle in the 2 dietary treatments receiving monensin supplementation tended (P ≤ 0.09) to increase average daily gain and gain to feed ratio on the first 112 days on feed compared with cattle in the control treatment. There were no effects (P ≥ 0.22) of feed additive supplementation on hot carcass weight (380.7 ± 14.7 kg), dressing percentage (61.83 ± 1.05%), kidney, pelvic, and heart fat (3.32 ± 0.19%), backfat thickness (0.73 ± 0.12 cm), longissimus muscle area (83 ± 4.83 cm2), marbling score (494 ± 48), and calculated yield grade (2.94 ± 0.24). Moreover, there were no effects (P ≥ 0.55) of dietary treatment on percent of liver abscess incidence, regardless of diet, calf-fed steers in the current study had 3.75% of liver with abscess.

423 Effects of Prescribed Fire Timing on Stocker Cattle Performance and Native Plant Species Composition in the Kansas Flint Hills

Abstract Ranchers in the Kansas Flint Hills apply spring-season prescribed fire to improve growth performance of yearling stocker calves, increase native warm-season grass production, and reduce encroachment of woody and invasive plant species. Shifting prescribed fire application from spring (i.e., April) to late summer (i.e., August) or early fall (i.e., September) can reduce Sericea lespedeza infestation, increase native forb diversity, and improve air quality by distributing smoke produced from burning the Flint Hills throughout the year. Effects of late-summer or early-fall prescribed fire on yearling grazing cattle performance is unknown; therefore, our objective was to determine the impact of prescribed-fire timing on growth performance of yearling grazing cattle and plant community characteristics in the Kansas Flint Hills. Over a four-year period, 18 pastures were grouped by watershed and each watershed was assigned to one of three prescribed-fire treatments (24 pastures/treatment): spring (9 April ± 5.1 d), summer (23 August ± 4.9 d), or fall (29 September ± 8.7 d). Burn treatments were applied in years 1, 2, and 3 but were not applied in year 4 due to unfavorable burn conditions. Over 4 consecutive grazing seasons, 1,416 yearling calves (initial BW = 304 ± 49.6 kg) were grazed from May to August following prescribed fire application. Calves were grazed for 90 d at a targeted stocking density of 280 kg live-weight· ha-1. A permanent 100 m transect was established in each pasture and was used to determine plant species composition and soil cover using a modified step-point method. Plant species composition was determined annually in June. Data were analyzed as a completely random design using a mixed model. The final model contained treatment as a fixed effect and year and pasture within treatment as random effects. Average daily gain (ADG) tended to be greater (P = 0.06) for spring-burned pastures compared with fall-burned pastures, whereas ADG for summer-burned pastures were intermediate. Proportions of bare soil were greater (P < 0.01) in spring-burned pastures compared with summer- and fall-burned pastures. Conversely, proportions of litter on the soil surface were greatest (P < 0.05) in summer, intermediate (P < 0.05) in fall, and least (P < 0.01) in spring-burned pastures. Total grass, native grass, total forb, and native forb basal cover did not differ (P ≥ 0.13) among treatments. Conversely, basal cover of nectar-producing forbs was greater (P < 0.01) in fall-burned pastures compared with spring- and summer-burned pastures. Overall, fall prescribed-fire tended to reduce ADG; however, stocker cattle growth performance and native rangeland plant composition was similar between spring- and summer-burned pastures.

15 Industry Perspective on the Value and Challenges of Amino Acid Feeding in Ruminants

Abstract The focus of this presentation is to provide a perspective on the value and challenges to meeting the amino acid needs of ruminant livestock based on experiences in the feed manufacturing and ruminant feeding industries. Monogastric nutritionists have demonstrated extensively the value of having an ideal amino acid profile from the point of growth, efficiency, and environmental stewardship. For the ruminant animal, the challenges of protein fractionation, deamination and re-synthesis of amino acids in the rumen create greater complexity both for research advancement as well as practical application to delivery of amino acid technology. In this presentation, amino acid supplies, protein synthesis, the impact of overlaid growth-promoting technologies, and return relative to investment of amino acid-feeding technology will be discussed. In addition to discussing the biological and economic aspects of amino acid feeding, thoughts on the means of delivering amino acid technology within the constraints of feed manufacturing and feeding practices common to ruminant livestock will be discussed. As genetics for improved lean growth in cattle continue to evolve, amino acid nutrition should be at the forefront of investigation of nutritional technologies which allow the improvement in genetic potential to be fully expressed. In addition to the potential value that amino acid feeding brings to ruminant livestock growth and efficiency, it also stands to merit environmental stewardship within this industry.

308 Zinc Supplementation and Implant Abscess Effects on Growth Performance and Immune System of Growing Beef Steers

Abstract Zinc is beneficial in growth and immune system function in cattle. Angus-cross steers (n = 72; initial BW = 261 ± 14 kg) were used in this 58-day study to determine the effects of supplemental Zn on growth, trace mineral status, and circulating immune cell populations. On d 0, steers received a Component E-S with Tylan implant (Elanco Animal Health, Greenfield, IN) and were stratified by BW into twelve GrowSafe-equipped pens. Dietary treatments included: control (CON; no supplemental Zn), Zn100 (100 mg supplemental Zn/kg DM), and Zn150 (150 mg supplemental Zn/kg DM). Supplemental Zn was provided as Zn sulfate, and other trace minerals were supplemented at NASEM (2016) recommendations. Individual BW was recorded on days -1, 0, 12, 13, 27, 28, 56, and 57. Blood was collected from 9 steers per treatment on d 13 for immune cell population and function assays. Liver biopsies were conducted on 18 steers per treatment on d 14. On d 16, implant abscesses (ABSC) were evaluated, and all steers were treated with meloxicam (285 mg). Data were analyzed using the Mixed procedure of SAS (Cary, NC) with fixed effects of treatment and ABSC prevalence using steer as the experimental unit. Abscess prevalence among treatments was analyzed using Proc Glimmix. Sixty percent of steers had ABSC; ABSC prevalence was similar by treatment (P = 0.67). Steers without ABSC had greater (P = 0.04) ADG d 0 to 13 and tended to have greater (P = 0.09) ADG d 0 to 57. There was also a tendency (Trt × ABSC; P ≤ 0.09) for steers without ABSC to have greater ADG and G:F from d 14 to 27 in CON and Zn100 while within Zn150 steers without ABSC tended to have lesser ADG and G:F than ABSC steers. No other treatment by ABSC or treatment effects (P ≥ 0.14) for growth performance were observed. There were no treatment by ABSC effects for immune cell populations on d 13 (P ≥ 0.26). In Zn150 steers, activated natural killer and gamma delta T cells were increased (P ≤ 0.03) on d 13. Similarly, CD21+ MHC IIhi B cells tended to be increased in Zn150 steers (P = 0.08). Steers with ABSC had increased relative frequency of CD5+ and CD21+ B cells (P ≤ 0.05) and tended to have increased natural killer and CD21+ MHC IIhi B cells (P ≤ 0.09). In addition, steers without ABSC had greater liver Mn on d 14 than ABSC steers (P = 0.05). There were no other effects on liver trace mineral concentrations (P ≥ 0.17). These observations suggest Zn supplementation has greater impact on the cellular immune system, while ABSC have a greater effect on B cells and the adaptive immune system.

Effect of the inclusion of rumen-protected amino acids in the diet of growing beef cattle on animal performance and meat quality

IntroductionThis study investigated the impact of rumen-protected amino acids on beef cattle's growth, fattening performance, and meat quality.MethodsTwo groups of 40 Montbeliard steers (237.8 ± 30 kg body weight) were housed separately and fed, with mono-tunnel feeders, either a control diet (CON) or a diet containing rumen-protected lysine and methionine with 3% less crude protein (APR). Feed consumption and weight were tracked in all animals, and meat quality analysis focused on the longissimus muscle, with 10 steers randomly selected from each treatment.Results and discussionResults for overall performance revealed no significant differences in body weight, average daily gain (ADG), and concentrate conversion ratio between the CON and APR diets (p > 0.05). However, during the final 90 days of the trial, the APR group showed significantly higher ADG (p < 0.05) than the CON group, while the concentrate conversion ratio was significantly higher (p < 0.05) in the CON group compared to the APR group. The hot carcass weight, dressing percentage, and carcass conformation did not differ significantly between the CON and APR diets (p > 0.05). There was a slight tendency (p = 0.06) for higher fatness score in the CON group. Regarding meat composition, the diet did not significantly affect proximate composition, but a tendency (p = 0.059) for higher crude protein content in APR cattle's meat compared to the CON group was observed. The APR meat showed slightly lower levels of C17:1 (0.56% vs. 0.72%) and C18:1n9 (31.7% vs. 34%). There was a tendency for C14:0 to be lower (P = 0.07), and for C16:0, C18:2 and polyunsaturated fatty acids (PUFA) to be greater in meat from cattle fed APR compared to CON. However, meat quality attributes like pH, water-holding capacity, color, and texture were similar in both CON and APR groups (p > 0.05). The findings indicate that utilizing rumen-protected amino acids enables formulating diets with reduced crude protein levels while enhancing nitrogen utilization efficiency for protein synthesis in intensively reared steers. Importantly, these dietary improvements do not adversely affect meat quality.

Lysinibacillus fusiformis: a novel fibrolytic native strain from the rumen microbiome that increases in vitro digestibility of central agricultural residues

ABSTRACT Increasing the digestibility of agricultural residues is one goal of sustainable livestock production, and the role of rumen microbiome-feed interaction is critical for efficient digestion. This study was aimed at isolating and evaluating in vitro the effect on dry-matter digestibility (IVDMD), relative feed values (RFV), volatile fatty acid (VFA) synthesis, pH changes, and gas production (GP) by the inclusion of native rumen strains in mixtures of corn, sorghum, and oat agricultural residues with ruminal fluid. The results show that an inoculum of 1 × 1010 colony-forming unit per millilitre (CFU/mL) of the aero-tolerant native rumen strain Lysinibacillus fusiformis increases the IVDMD, RFV, and VFA values of all mixtures. During agricultural residue fermentation, the pH was stable, and propionic acid was the primary fatty acid synthesized, indicating increased energy availability for efficient cattle growth performance while limiting molecular hydrogen (H2) synthesis for conversion to methane (CH4). These results suggest that L. fusiformis could be used as a direct-feed microbial to promote sustainable livestock production. To the best of our knowledge, this is the first report to link the fermentation of fibrous agricultural residues in ruminal fluid inoculated with a fibrolytic native strain and digestibility in favour of increasing the efficiency of livestock production.

Effects of Different Generations and Sex on Physiological, Biochemical, and Growth Parameters of Crossbred Beef Cattle by Myostatin Gene-Edited Luxi Bulls and Simmental Cows.

(1) Background: Myostatin (MSTN) is a protein that regulates skeletal muscle development and plays a crucial role in maintaining animal body composition and muscle structure. The loss-of-function mutation of MSTN gene can induce the muscle hypertrophic phenotype. (2) Methods: Growth indexes and blood parameters of the cattle of different months were analyzed via multiple linear regression. (3) Results: Compared with the control group, the body shape parameters of F2 cattle were improved, especially the body weight, cross height, and hip height, representing significant development of hindquarters, and the coat color of the F2 generation returned to the yellow of Luxi cattle. As adults, MSTN gene-edited bulls have a tall, wide acromion and a deep, wide chest. Both the forequarters and hindquarters are double-muscled with clear muscle masses. The multiple linear regression demonstrates that MSTN gene-edited hybrid beef cattle gained weight due to the higher height of the hindquarters. Significant differences in blood glucose, calcium, and low-density lipoprotein. Serum insulin levels decreased significantly at 24 months of age. MSTN gene editing improves the adaptability of cattle. (4) Conclusions: Our findings suggest that breeding with MSTN gene-edited Luxi bulls can improve the growth and performance of hybrid cattle, with potential benefits for both farmers and consumers.

The potential role of Indigofera zollingeriana as a high-quality forage for cattle in Indonesia

Ownership of cattle in Indonesia is dominated by smallholder farmers, who rely heavily on low-quality mature grasses and crop residues as animal feed. Forage tree legumes (FTLs) provide a practical and profitable option for supplying nutrients limiting cattle growth and reproduction, especially during the dry months. Indigofera zollingeriana is a tall, high-yielding plant under investigation as feed, which can produce edible plant material exceeding 4 t dry matter (DM)/ha/harvest, when cut every 68 days. I. zollingeriana is adapted to a relatively wide range of climatic conditions and soil-types, with notable high tolerance of acidic soils. Forage quality is high, with high crude protein (265 g/kg DM average) and low fiber (367 g neutral detergent fiber/kg DM) concentrations and high in vitro DM digestibility (72.6%). It contains no identified anti-nutritional compounds but concentration of indospicine, a recognized toxic contaminant in some species of Indigofera, is currently unknown. Information on animal responses to feeding I. zollingeriana is limited, especially for cattle, but research suggests growth responses in goats are comparable with those for other available FTLs. Research to date suggests I. zollingeriana could be a valuable addition to FTLs currently available in Indonesia, especially for acidic soils, but further information is required on performance on saline soils, persistence under regular harvesting, indospicine status, acceptance by cattle and effects on their productivity.

Comparative Analysis of Statistical Regression Models for Prediction of Live Weight of Korean Cattle during Growth

Measuring weight during cattle growth is essential for determining their status and adjusting the feed amount. Cattle must be weighed on a scale, which is laborious and stressful and could hinder growth. Therefore, automatically predicting cattle weight could reduce stress on cattle and farm laborers. This study proposes a prediction system to measure the change in weight automatically during growth using three regression models, using environmental factors, feed intake, and weight during the period. The Bayesian inference and likelihood estimation principles estimate parameters that determine the models: the weighted regression model (WRM), Gaussian process regression model (GPRM), and Gaussian process panel model (GPPM). A posterior distribution was derived using these parameters, and a weight prediction system was implemented. An experiment was conducted using image data to evaluate model performance. The GPRM with the squared exponential kernel had the best predictive power. Next, GPRMs with polynomial and rational quadratic kernels, the linear model, and WRM had the next-best predictive power. Finally, the GPRM with the linear kernel, the linear model, and the latent growth curve model, and types of GPPM had the next-best predictive power. GPRM and WRM are statistical probability models that apply predictions to the entire cattle population. These models are expected to be useful for predicting cattle growth on farms at a population level. However, GPPM is a statistical probability model designed for measuring the weight of individual cattle. This model is anticipated to be more efficient when predicting the weight of individual cattle on farms.

Forecasting husbandry development using time series

Building time series models based on historical data is a pressing challenge in the agricultural sector. This is essential, as analysing and predicting processes related to the food security of the state, region, and business entities are of paramount importance in management. With the help of forecasts, enterprises can adjust their production activities in such a way as to satisfy demand and deliver products to consumers on time. The research aims to predict the trends in the growth of cattle and cow populations and identify the most suitable forecasting timeframe. Statistical methods related to autoregression are used for this type of analysis: autoregressive models, moving average models or a combination of both, integrated variable structure models, and models that include seasonal effects and exogenous factors with an autoregressive and moving average component in the model. Monthly statistical data on the number of cattle and cows are used, among them mean, standard deviation, minimum and maximum values, asymmetry, and kurtosis. The dynamics of the decrease in the number of cattle and cows are shown. The studied series were checked for stationarity. The time series data for the cattle population underwent a Box-Cox transformation. The optimal parameters of the models used are given. Predictive values for periods (months) were obtained and the change in the number of cattle over the last 15 years was analysed. Constructed time series are compared with the actual values, which are illustrated in the graphs. Estimates of rootmean-square deviation, and mean absolute percentage error for different forecasting terms are given. By comparing these estimates for different time intervals, the optimal period for the forecast (24 months) was determined. This study allows farms and enterprises in the industry to predict a possible number of products (milk, meat) that could be collected or obtained in the future. It helps to take the necessary management steps: plan resource needs, improve efficiency, increase profits, reduce costs, and adapt to changes in the market

Trace mineral concentrations and accretion rates in the empty body and body tissues of growing Fleckvieh (German Simmental) bulls.

This research project aimed to generate basic data for specifying the trace mineral requirements of Fleckvieh (German Simmental) bulls. Hence, the concentrations of the trace minerals iron (Fe), zinc (Zn), copper (Cu), and manganese (Mn) in the empty-body and body tissue fractions of growing Fleckvieh bulls slaughtered at 120-780 kg live weight were determined. Results were used to calculate trace mineral accretion rates. Fe and Zn represented the largest shares in the animals' bodies. The Zn accretion increased, while Mn accretion steadily declined during cattle growth. Fe accretion attained a maximum at 400 kg live weight. Cu accretion declined until 600 kg live weight and then increased slightly afterwards. The provided data may be used to adjust the recommendations with respect to the trace mineral requirements of growing Fleckvieh bulls.

Computer Vision Driven Precision Dairy Farming for Efficient Cattle Management

Precision Dairy Farming (PDF)” or “The Per Animal Approach” can be enhanced through the implementation of three-dimensional computer vision, which offers improved cattle identification, disease monitoring, and growth assessment. The integration of 3D vision systems is particularly vital for advancing dairy farming practices in the next generation. These systems facilitate the automation of various animal husbandry tasks, including monitoring, herding, feeding, milking, and bedding of animals. The applications of 3D computer vision in PLF encompass diverse platforms, such as 3D camera installations for monitoring cow walking postures, and intelligent systems that interact safely with animals, capable of identifying dairy cattle and detecting health indicators like animal identification, recognition, body condition score, and lameness. To be effective, systems must be adaptable to unconstrained environments, varying herd characteristics, weather conditions, farmyard layouts, and animal-machine interaction scenarios. Considering these requirements, this paper proposes the application of emerging computer vision and artificial intelligence techniques in dairy farming. This review encourages future research in three-dimensional computer vision for cattle growth management and its potential extension to other livestock and wild animals

Multitrait meta-analyses identify potential candidate genes for growth-related traits in Holstein heifers

Understanding the underlying pleiotropic relationships among growth and body size traits is important for refining breeding strategies in dairy cattle for optimal body size and growth rate. Therefore, we performed single-trait GWAS for monthly-recorded body weight (BW), hip height, body length, and chest girth from birth to 12 mo of age in Holstein animals, followed by stepwise multiple regression of independent or lowly-linked markers from GWAS loci using conditional and joint association analyses (COJO). Subsequently, we conducted a multitrait meta-analysis to detect pleiotropic markers. Based on the single-trait GWAS, we identified 170 significant SNPs, in which 59 of them remained significant after the COJO analyses. The most significant SNP, located at BTA7:3,676,741, explained 2.93% of the total phenotypic variance for BW6 (BW at 6 mo of age). We identified 17 SNPs with potential pleiotropic effects based on the multitrait meta-analyses, which resulted in 3 additional SNPs in comparison to those detected based on the single-trait GWAS. The identified quantitative trait loci regions overlap with genes known to influence human growth-related traits. According to positional and functional analyses, we proposed HMGA2, HNF4G, MED13L, BHLHE40, FRZB, DMP1, TRIB3, and GATAD2A as important candidate genes influencing the studied traits. The combination of single-trait GWAS and meta-analyses of GWAS results improved the efficiency of detecting associated SNPs, and provided new insights into the genetic mechanisms of growth and development in Holstein cattle.

Genotype by Prenatal Environment Interaction for Postnatal Growth of Nelore Beef Cattle Raised under Tropical Grazing Conditions.

The prenatal environment is recognized as crucial for the postnatal performance in cattle. In tropical regions, pregnant beef cows commonly experience nutritional restriction during the second half of the gestation period. Thus, the present study was designed to analyze the genotype by prenatal environment interaction (G × Epn) and to identify genomic regions associated with the level and response in growth and reproduction-related traits of beef cattle to changes in the prenatal environment. A reaction norm model was applied to data from two Nelore herds using the solutions of contemporary groups for birth weight as a descriptor variable of the gestational environment quality. A better gestational environment favored weights until weaning, scrotal circumference at yearling, and days to first calving of the offspring. The G × Epn was strong enough to result in heterogeneity of variance components and genetic parameters in addition to reranking of estimated breeding values and SNPs effects. Several genomic regions associated with the level of performance and specific responses of the animals to variations in the gestational environment were revealed, which harbor QTLs and can be exploited for selection purposes. Therefore, genetic evaluation models considering G × Epn and special management and nutrition care for pregnant cows are recommended.

Plasma Metabolomic Profiling after Feeding Dried Distiller’s Grains with Solubles in Different Cattle Breeds

Dried distiller’s grains with solubles (DDGS) are rich in nutrients and can enhance animals’ growth and immunity. However, there are few reports on the effects of a diet of DDGS on plasma metabolism and the related action pathways in domestic animals. In this study, groups of Guanling yellow cattle (GY) and Guanling crossbred cattle (GC) having a basal diet served as the control groups (GY-CG and GC-CG), and DDGS replacing 25% of the diet of GY and GC served as the replacement groups (GY-RG and GC-RG), with three cattle in each group. Plasma samples were prepared for metabolomic analysis. Based on multivariate statistical and univariate analyses, differential metabolites and metabolic pathways were explored. Twenty-nine significantly different metabolites (p < 0.05) were screened in GY-RG compared with those in GY-CG and were found to be enriched in the metabolic pathways, including choline metabolism in cancer, linolenic acid metabolism, and amino acid metabolism. Nine metabolites showed significant differences (p < 0.05) between GC-RG and GC-CG and were mainly distributed in the metabolic pathways of choline metabolism in cancer, glycerophospholipid metabolism, prostate cancer metabolism, and gonadotropin-releasing hormone (GnRH) secretion. These results suggest that a DDGS diet may promote healthy growth and development of experimental cattle by modulating these metabolic pathways. Our findings not only shed light on the nutritional effects of the DDGS diet and its underlying mechanisms related to metabolism but also provide scientific reference for the feed utilization of DDGS.

Zinc supplementation and ractopamine hydrochloride impact gene expression of zinc transporters in finishing beef steers

Zinc is a trace mineral of interest for optimizing growth in feedlot cattle due to its roles in many physiological functions, including growth. Twenty-four Angus-cross steers (467 ± 13 kg) were used to assess the effects of supplemental Zn and ractopamine hydrochloride (RAC) on trace mineral concentrations and muscle gene expression. Four GrowSafe-equipped pens were randomly assigned to treatments (1 pen of six steers/treatment): 0 (CON), 60 (LOW), 120 (MED) or 180 (HI) mg supplemental Zn/kg DM (Availa-Zn, Zinpro). Dietary Zn treatments were initiated on d 0 and RAC supplementation (300 mg·steer·-1·d-1; Actogain45, Zoetis) began on d 53. Blood, liver and muscle (longissimus thoracis) samples were collected from all steers on d -4, 48, and 67. The LOW treatment was removed from gene expression analyses due to < 3 steers being represented for 14 of 22 genes. Data were analyzed using ProcMixed of SAS with the fixed effect of treatment and steer as the experimental unit; orthogonal linear and quadratic contrast statements were used to compare treatments. On d 48 and 67, there were linear and quadratic trends for plasma Zn to be greater in Zn-supplemented steers than CON (P ≤ 0.10). On d 48, there was a tendency for a quadratic decrease on the expression of SLC30A4 (P ≤ 0.07) but no other differences due to treatment. On d 67, several genes involved in Zn transport and storage (MTA1, SLC39A7, SLC39A8, SLC39A9, SLC39A10, SLC39A13) were decreased (P ≤ 0.08), suggesting increased growth influences intracellular Zn trafficking and demands.