Maternal ability (milk and environment) in beef cattle is one of the most important traits influencing weaning weight of the calf, but amount and composition of milk produced by the dam is difficult to measure. The assessment of polymorphisms of candidate genes related to milk composition could indirectly enlighten this perspective. In the present study, the frequency of αs1-casein 1175AG and g26181A>G; κ-casein 13068 (CSN3 AB1) and 13104 (CSN3 AB2) loci, β-lactoglobulin variants 3984GA and 5263CT, Diacyl glycerol transferase K232A, and Stearoyl CoA desaturase A702G and A762G polymorphisms were estimated in Gray and Red Brahman, Nellore, Guzerat, Gir, Indubrazil, and Sardo Negro registered sires from Mexico. Most of the documented favourable alleles were found in low frequency in most of the evaluated breeds, except for β-lactoglobulin, in which the presence of favourable alleles might represent an opportunity for marker-assisted introgression. The relevance of the findings for each variation and implications from the outcomes are discussed.

The aim of this study was to estimate genetic parameters for dairy traits (daily milk yield (DMY), daily milk fat yield (DMFY), and daily milk protein yield (DMPY)) and somatic cell score (SCS) of Iranian Murciano-Granadina goats. The analysis involved 99,839 records from 4,307 does, spanning from 2015 to 2021. A single-trait animal model was used to obtain estimates of genetic and residual (co)variances and heritabilities. In the model, both fixed effects (birth year, parity, litter size, age dam (day)) and random effects (additive animal genetic effects) were considered. R software was used to evaluate environmental effects, assess the model, examine genetic and phenotypic trends, and determine genetic-environmental correlations. Additionally, variance components and heritability were estimated using the Gibbs1f90 software. The heritability of dairy traits and SCS trait, namely DMY, DMFY, DMPY, and SCS, was estimated to be 0.244, 0.133, 0.188, and 0.023, respectively. The genetic correlations between DMY and DMFY, DMY and DMPY, DMY and somatic cell score (SCS), DMFY and DMPY, DMFY and SCS, and DMPY and SCS were 0.07, 0.16, 0.42, –0.08, –0.005, and 0.04, respectively. The study found moderate heritability for milk yield traits and low heritability for somatic cell score. Genetic correlations varied, with the strongest correlation between daily milk yield and somatic cell score, indicating useful genetic linkages for selective breeding.

Reducing nitrogen (N) fertilizer application is a sustainable practice in rice production. The effects of reducing N fertilizer input on grain yield and rice quality of early- and late-season dual-use rice (ELDR) in South China remain uncertain. Therefore, a short-term field trial was conducted with a high-yielding ELDR cultivar (Yuehesimiao, YHSM) and a low-yielding ELDR cultivar (Meixiangzhan 2, MXZ). The rice was cultivated with a 20% reduced N application rate (RN2), a 10% reduced rate (RN1) and the conventional N application rate (CN). In the early season, compared to CN, RN2 reduced the grain yield of YHSM and MXZ by an average of 16.1 and 6.6%, respectively, while RN1 lowered YHSM grain yield by 11.2% on average and had no effect on MXZ yield. In addition, RN2 decreased the milling and eating qualities of the two cultivars in the early season, while RN1 did not alter their milling, appearance or eating qualities. In the late season, neither RN2 nor RN1 affected grain yield or rice quality for both cultivars. Therefore, short-term reductions of 10 and 20% in N application could maintain grain yield and rice quality at current N fertilizer application rates in the late season. However, the early-season results only recommended a 10% reduced N fertilizer application rate for low-yielding ELDR cultivars to sustain grain yield and rice quality. The findings of this study can provide a theoretical basis for N management of ELDR in South China.

The investigation of structural variants that may govern complex traits has significant importance. This is particularly true for the crossbred dairy cattle of Pakistan, which are deemed ideal for achieving optimal milk production and enhanced environmental adaptability in tropical conditions. This research detected and described copy number variation regions (CNVR) within the crossbred cattle genome. A GGP_HDv3_C chip containing 139,376 SNPs was utilized to genotype a cohort of 81 animals. In this study, 1055 CNVs were obtained after quality control, distributed across animals and encompassing all autosomes. From these, 268 CNVRs were detected, which covered 31.03 megabases, representing approximately 1.24% of the bovine genome. Functional analysis of these regions yielded 97 genes primarily associated with the immune and defense systems. Additionally, other observed categories encompassed production, health and reproduction. These findings enhanced the CNV map of bovines, offering the variant identification linked to traits subject to selection in both crossbred and indicine breeds of cattle.

The effects of abomasal infusion of corn starch and β-hydroxybutyrate (BHB) on hindgut microbial fermentation characteristics and end-products in early lactation dairy cows were determined via in vitro gas production (GP). Four substrates, either fibre or starch sources differing in expected rate of degradability (slow – cellulose and corn grain; rapid – beet pulp and pregelatinized corn flour), were incubated with faecal inoculum from cows abomasally infused with water only, 1.5 kg corn starch/d + 0.0 mol BHB/d, 3.0 kg corn starch/d + 0.0 mol BHB/d, 0.0 kg corn starch/d + 8.0 mol BHB/d, 1.5 kg corn starch/d + 8.0 mol BHB/d, or 3.0 kg corn starch/d + 8.0 mol BHB/d in a 6 × 6 Latin square design. In vitro GP was measured using an automated GP system with methane (CH4) measured at specific times. After 72 h, volatile fatty acids (VFA), pH, ammonia, and in vitro organic matter digestibility (IVOMD) of incubation fluid were determined. Infusion of BHB had limited effect on hindgut microbial fermentation. Infusion of 3.0 kg corn starch/d increased GP at 3 h of incubation for all substrates but resulted in lower total GP, CH4 production, pH, ammonia concentration, and IVOMD after 72 h, while increasing total VFA concentration and molar proportions of propionate and butyrate vs. 0.0 and 1.5 kg corn starch/d infusions. Among substrates, IVOMD of cellulose was most affected by 3.0 kg corn starch/d infusion. Results suggest that in vitro fermentative activity of hindgut microbes decreases when higher levels of starch enter the hindgut.

In working towards meeting the rapidly rising demand for livestock products in the face of challenges such as climate change, limited forage land availability and inadequacies in water availability and quality, it is imperative to consider sustainability in farm or grazing land management and water resources conservation as well as biodiversity management and conservation, etc. Geophysics, GIS, remote sensing, etc., have been useful tools. Emerging technologies such as biotechnology, advanced sensor technologies, machine learning algorithms, internet of things, artificial intelligence, unmanned aerial vehicles, robotics, etc., are also being employed in agriculture and other aspects of human concerns. There are potentials for better utilization of these emerging technologies and more in livestock production and management. However, a limitation is that relevant knowledge and skills are still relatively inadequate, especially in developing countries; hence the need for this review, which is an enhancement of knowledge for research and improved productivity. Efforts should be made to advance in knowledge and skills acquisition so as to optimize this development for improved livestock production and management.

This study evaluated the effects of capsaicin (CAP) supplementation on the intake, nutrient digestibility, ruminal fermentation, nitrogen balance, microbial protein synthesis and health traits of bulls managed on pasture. Eight crossbred (Holstein x Zebu) cattle averaging 313 ± 31 kg of body weight (BW) were arranged in a replicated 4 × 4 Latin square design (one square of four bulls, rumen fistulated with 4-inch silicone cannulas and one square of four non-fistulated bulls), which were kept on Pangola grass pasture (Digitaria decumbens). Each experimental period consisted of 21 days, with 7 days for data collection (no washout between periods). Bulls were randomly assigned to the following treatments: CON (control): concentrate supplementation at 0.5% live weight (BW) and no additive (CAPCIN®), or concentrate supplementation at 0.5% BW in association with CAPCIN® (NutriQuest, Campinas, Brazil) fed at the inclusion rates of 150 (CAP150), 300 (CAP300) and 450 (CAP450) mg/animal/day. Digestibilities of dry matter, organic matter and neutral detergent fibre showed quadratic responses to CAP supplementation. Rumen pH linearly increased with CAP supplementation. The numbers of lymphocytes and eosinophils were linearly increased with CAP supplementation. The use of encapsulated pepper in supplements of crossbred (Holstein x Zebu) bulls managed on D. decumbens pasture up to 450 mg/animal/day improves nutrients digestibility and ruminal fermentation and can positively influence the health status of beef cattle managed under tropical conditions.

DNA barcoding approaches have been successfully applied for estimating diet composition. However, an accurate quantification in the diets of herbivores remains to be achieved. In the current study, we present a novel methodology that reveals the relationship between the actual proportions (by mass) of each herbage species in the diets and the relative proportions of the ITS2 gene sequences obtained from faecal samples to evaluate the diet composition of sheep in a meadow steppe. Nine common and 12 rare species of plants were employed for formulating 6 diets, along with the addition of feed supplements for improving the growth performance of sheep. Faecal samples were collected for DNA analysis over the period spanning days 7–12. A significant positive correlation (Spearman’s ρ = 0.389) was obtained between the actual proportions (by mass) of the herbage in the diet provided and the relative abundance of ITS2 sequences obtained from the faecal samples. A significant regression coefficient was found between the relative abundance of all common species and their respective herbage mass proportions. The accuracy of the relation equations, evaluated by utilizing the similarity coefficient, showed 84.69% similarity between the actual diet composition and the correct percentage. Taken together, the current study has provided empirical evidence for the accuracy and applicability of ITS2 as a DNA barcode for obtaining quantitative information about the diet composition of sheep grazing in species-rich grasslands.