Productive performance and milk composition of dairy ewes supplemented with corn silage (Zea mays L.), sunflower (Helianthus annuus) silage and their mixture.

The work reported in the Research Communication investigated in vitro rumen gas kinetics and fermentation profile as well as in vivo performance of lactating ewes fed corn silage (CS), sunflower silage (SFS) and their 50 : 50 mixture (CS-SFS). For the in vivo experiment, nine early-lactation Suffolk × Texel ewes were grouped in a replicated 3 × 3 Latin square design of three 21-d periods. Treatments were based on ad libitum CS, SFS, and CS-SFS supplemented with concentrate at 48 g/kg LW0.75. In vitro results showed that the CS had the highest dry matter degraded substrate and microbial crude protein production followed by CS-SFS. The in vivo data showed that animals fed on CS had higher digestibility of dry matter and organic matter than CS-SFS, while SFS were intermediate. Nitrogen (N) intake, fecal N excretion, and urine N excretion were similar between groups, however, milk N excretion was lower in SFS than CS. Milk yield was higher for CS and CS-SFS than SFS group, however, SFS-fed ewes had higher milk fat content than either CS or CS-SFS (all differences reported here were significant, P < 0.05 or better). Overall, CS-SFS could be used as dietary roughage for dairy ewes without deleterious effects on nutrient intake, N-balance and milk yield whilst potentially offering a more sustainable alternative to CS.

Inclusion of chia seeds (Salvia hispanica L.) and pumpkin seeds (Cucurbita moschata) in dairy sheep diets.

Chia (Salvia hispanica L.) seed (CS) and Pumpkin (Cucurbita moschata) seed (PS) are used in ruminant diets as energy sources. The current experiment studied the impact of dietary inclusion of CS and PS on nutrient intake and digestibility, milk yield, and milk composition of dairy sheep. Twelve primiparous Texel × Suffolk ewes [70 ± 5 days in milk (DIM); 0.320 ± 0.029 kg milk yield] were distributed in a 4 × 3 Latin square design and fed either a butter-based control diet [CON; 13 g/kg dry matter] or two diets with 61 g/kg DM of either CS or PS. Dietary inclusion of CS and PS did not alter live weight (p >0.1) and DM intake (p >0.1). However, compared to the CON, dietary inclusion of both CS and PS increased the digestibility of neutral detergent fiber (p <0.001) and acid detergent lignin (p < 0.001). Milk production (p = 0.001), fat-corrected milk (p < 0.001), and feed efficiency (p < 0.001) were enhanced with PS, while the highest milk protein yield (p < 0.05) and lactose yield (p < 0.001) were for CS-fed ewes. Compared to the CON diet, the ingestion of either CS and/or PS decreased (p < 0.001) the C16:0 in milk. Moreover, both CS and PS tended to enhance the content of C18:3n6 (p > 0.05) and C18:3n3 (p > 0.05). Overall short-term feeding of CS and/or PS (up to 6.1% DM of diet) not only maintains the production performance and digestibility of nutrients but also positively modifies the milk FA composition.

Toward assessing the role of dietary fatty acids in lamb's neurological and cognitive development.

Understanding and measuring sheep cognition and behavior can provide us with measures to safeguard the welfare of these animals in production systems. Optimal neurological and cognitive development of lambs is important to equip individuals with the ability to better cope with environmental stressors. However, this development can be affected by nutrition with a special role from long-chain fatty acid supply from the dam to the fetus or in lamb's early life. Neurological development in lambs takes place primarily during the first two trimesters of gestation. Through late fetal and early postnatal life, the lamb brain has a high level of cholesterol synthesis. This rate declines rapidly at weaning and remains low throughout adulthood. The main polyunsaturated fatty acids (PUFA) in the brain are ω-6 arachidonic acid and ω-3 docosahexaenoic acid (DHA), which are elements of plasma membranes' phospholipids in neuronal cells. DHA is essential for keeping membrane integrity and is vital for normal development of the central nervous system (CNS), and its insufficiency can damage cerebral functions and the development of cognitive capacities. In sheep, there is evidence that supplying PUFA during gestation or after birth may be beneficial to lamb productive performance and expression of species-specific behaviors. The objective of this perspective is to discuss concepts of ruminant behavior and nutrition and reflect on future research directions that could help to improve our knowledge on how dietary fatty acids (FA) relate to optimal neurological and cognitive development in sheep.

Milk Yield and Milk Fatty Acids from Crossbred F1 Dairy Cows Fed on Tropical Grasses and Supplemented with Different Levels of Concentrate.

The objective of this study was to determine milk fatty acids from crossbred F1 dairy cows fed on tropical grasses and supplemented with different levels of concentrate. Twelve dairy cows (50% Holstein × 50% Brahman) with 60 days of lactation grazing tropical grasses were assigned to a Switchback design, with three periods of 15 days with different concentrate levels: 0, 150, 300 and 450 g /kg. Milk samples were obtained on the last five days of each experimental period. Milk yield and milk composition were not affected. Cows fed with 300 g/kg of concentrate had higher contents of C15:0 (p = 0.004), C22:0 (p = 0.031), and C24:0 (p = 0.013). C17:1 cis9 was higher (p = 0.039) with 150 g/kg and lowest with 450 g/kg. C18:1 cis9 was higher (p = 0.042) with 150 g/kg. C18:2n6trans was higher (p = 0.05) with 300 g/kg and lower (p = 0.018) with 450 g/kg. This study shows that adding up to 450 g/kg of concentrate to crossbred F1 dairy cows fed on tropical grasses does not have negative effects on milk yield and milk quality. Therefore, under these production conditions, farmers can rely on tropical grasses and reduce feeding costs.

Effect of different dietary inclusion levels of whole plant green tomato (Physalis philadelphica) silage on nutrient intake and digestibility, and in vitro rumen fermentation kinetics in sheep.

Mexico has many agricultural by-products that can be used for animal feed, and green tomatoes are produced throughout the country and can be an alternative to overcome the high prices of cereal-based feeds. This study determined in vitro fermentation kinetics, production performance, nutrient intake, digestibility, and nitrogen balance from sheep supplemented with whole plant green tomato (GT) on corn silage (CS) based diets. For 21 days, eighteen Suffolk lambs (38 ± 4 kg of live weight) were grouped into three dietary GT inclusion levels to replace CS: a control diet based on 100% CS (GT0, 570 g /kg dry matter, DM), while 100 g/kg DM (GT100) and 200 g/kg DM (GT200) of GT were included as a replacement for CS. A completely randomized design was used to measure in vitro gas production, in vitro rumen fermentation, chemical composition, and in vivo parameters. In vitro gas production, "A" (ml/g DM), fermentation rates "B," (h-1), and "C" (h-½), were lower for GT200, while DM disappearance (mg/100mg) was lower for GT100 compared with GT0. Compared to GT0, GT100 and GT200 did not affect (P > 0.05) DM and organic matter (OM) intake (g/kgLW0.75). Ether extract intake was higher for GT0 and GT100 (P < 0.001) compared to GT200. Neutral detergent fiber (NDF) intake was higher (P < 0.05) for GT200 compared with GT0. Intake of lignin was higher (P < 0.001) for GT200 than that of GT0 and GT100. Digestibility coefficients for DM, OM, NDF, and Acid detergent fiber (ADF) were lower (P < 0.05) in GT100 than in the rest of the treatments. Nitrogen intake and N excreted in feces and urine were lower (P < 0.001) for GT0. N balance was negative for all treatments, being higher for GT200 (P < 0.05). Overall, the addition of GT at 100 or 200 g/kg DM in sheep diets negatively affects nutrient digestibility and N balance, so their dietary inclusion is not recommended.

Effect of the Inclusion of Bacillus spp. in Growing-Finishing Pigs' Diets: A Meta-Analysis.

This meta-analysis determined the effect of Bacillus spp. on growth performance of growing−finishing pigs and then assessed causes for the heterogeneity of responses detected using meta-regression. A database of 22 articles published from 2000 to 2020 was identified, and 9 articles fitted the selection criteria and were integrated in the final database. Statistical analysis was performed to analyze the effect size for ADG, average daily feed intake (ADFI), and F:G ratio using a standardized means difference (SMD) at a 95% confidence interval. A meta-regression analysis was used to investigate the cause of heterogeneity, using the individual SMD for each study assessment as the outcome and the associated SE as the measure of variance. Dietary Bacillus spp. supplementation had no effect on ADFI (SMD: −0.052, p = 0.138) and numerically increased ADG (SMD: 0.113, p = 0.081) and reduced the F:G ratio SMD: −0.127, p < 0.001). Meta-regression outcomes suggested that the number of animals per group was an essential component promoting heterogeneity in ADG. Overall, the inclusion of Bacillus spp. (median 486 mg/d) in growing−finishing pigs can increase ADG and can decrease the F:G ratio.

A Brief Update on the Challenges and Prospects for Goat Production in Mexico.

In Mexico, information on goat production is scarce and documenting goat production challenges and future perspectives could be of great value, not only for Latin America, but also for international players-including those from farms, industry, and academia. Therefore, the objective of this review is to provide current knowledge on goat production systems in Mexico and discuss current challenges and future perspectives for this animal production sector. In Mexico, more than 70% of goats are produced under extensive production systems in arid and semi-arid areas and roughly 25% are produced in intensive or semi-intensive systems. Main breeds are French Alpine, Saanen, Toggenburg, LaMancha, Nubian, Boer, and their crosses. The main challenges are correlated at different levels, where economic, social, and environmental issues are mixed and are closely associated with goat health and welfare. Newly available farming technologies could be an option that should be explored. Mexican goat farming systems will need to look at the animal, social, and environmental factors to promote sustainable production systems.

Feeding Forage Mixtures of Ryegrass (Lolium spp.) with Clover (Trifolium spp.) Supplemented with Local Feed Diets to Reduce Enteric Methane Emission Efficiency in Small-Scale Dairy Systems: A Simulated Study.

In cattle, greenhouse gas (GHG) emissions and nutrient balance are influenced by factors such as diet composition, intake, and digestibility. This study evaluated CH4 emissions and surpluses of crude protein, using five simulated scenarios of supplementation in small-scale dairy systems (SSDS). In addition, two pasture managements (cut-and-carry versus grazing) and two varieties of legumes (red clover vs. white clover) were considered. The diets were tested considering similar milk yield and chemical composition; CH4 emission was estimated using Tier-2 methodology from the Intergovernmental Panel on Climate Change (IPCC), and the data were analyzed in a completely randomized 5 × 2 × 2 factorial design. Differences (p < 0.05) were found in predicted CH4 emissions per kg of milk produced (g kg-1 FCM 3.5%). The lowest predicted CH4 emissions were found for S3 and S4 as well as for pastures containing white clover. Lower dietary surpluses of CP (p < 0.05) were observed for the control diet (1320 g CP/d), followed by S5 (1793 g CP/d), compared with S2 (2175 g CP/d), as well as in cut-and-carry management with red clover. A significant correlation (p < 0.001) was observed between dry matter intake and CH4 emissions (g-1 and per kg of milk produced). It is concluded that the environmental impact of formulating diets from local inputs (S3 and S4) can be reduced by making them more efficient in terms of methane kg-1 of milk in SSDS.

Effects of weather and other factors on milk production in the Churra dairy sheep breed

The objective of this study was to investigate the influence of meteorological and other factors on the quality and quantity of milk of the Spanish Churra sheep breed, based on an analysis of 359,808 milk controls from 9,904 ewes on 15 farms in 8 years. Daily milk yield (DMY), fat, protein, and lactose (%), and somatic cell count (SCC) data were obtained from monthly alternating milk controls. Mean, maximum, and minimum temperatures (T) (°C), mean relative humidity (RH) (%), wind speed (WS, m/s), mean solar radiation (SR, MJ/m2), and total rainfall (RF, mm) on the day before each milk control day were documented. Year, farm, number of lambing and stage of lactation, and all of the meteorological factors had asignificant (P < 0.0001) effect on DMY and milk quality. DMY and SCC differed among seasons (P < 0.001), and maximum DMY and minimum SCC occurred in spring, and minimum DMY and maximum SCC occurred in autumn. Fat, protein, and lactose content differed significantly (P < 0.001) among seasons, and fat and protein contents were highest in autumn. DMYwas highest in the second lambing of the ewe and steadily declined in subsequent lambings. SCC increased significantly from the first to the 10th lambing of the ewe. DMY, SCC, and fat content differed significantly (P < 0.001) among years. In conclusion, meteorological conditions had a significant effect on milk quality and production in Churra sheep conditions in a season-dependent manner such that factors such as temperature had the opposite effect on milk production in hot and cold seasons.(AU)

Concentrate supplementation on milk yield, methane and CO2 production in crossbred dairy cows grazing in tropical climate regions

The objective of this study was to evaluate the level of concentrate supplementation on the production and chemical composition of milk from 12 crossbred F1 dual-purpose cows (½ Bos taurus ½ Bos indicus) and estimate the emission of CH4, N2O, and CO2 gases. The study included 12 crossbred F1 dual-purpose cows over 60 days of lactation. The cows grazed on 28% tropical native grassland and 72% Brachiaria spp. and Cynodon neumfluensis, supplemented with 0, 150, 300, and 450g of concentrate per kg daily milk production, during three experimental periods of 15 days each in a crossover design. Pasture and concentrate samples were collected and were analyzed for dry matter, crude protein, neutral detergent fiber, and acid detergent fiber. Milk production (kg d-1) was recorded daily, nitrous oxide (N2O), and emissions from excreta and daily CH4 production were calculated. Results were analyzed with the SAS MIXED procedure. Concentrate supplementation in tropical crossbred dairy cows did not improve milk yield but increased CH4 and N2O production (P < 0.0001) per cow as the concentrate increased in the diet; the Ym factor from the tropical region yielded less CH4 than the IPCC Ym model (P < 0.0001). In conclusion, the calculation of CH4 using specific emission factors for the tropical climate region is better than the IPCC default emission factors in order not to overestimate the CH4 emissions.(AU)

Concentrate supplementation on milk yield, methane and CO2 production in crossbred dairy cows grazing in tropical climate regions

The objective of this study was to evaluate the level of concentrate supplementation on the production and chemical composition of milk from 12 crossbred F1 dual-purpose cows (½ Bos taurus ½ Bos indicus) and estimate the emission of CH4, N2O, and CO2 gases. The study included 12 crossbred F1 dual-purpose cows over 60 days of lactation. The cows grazed on 28% tropical native grassland and 72% Brachiaria spp. and Cynodon neumfluensis, supplemented with 0, 150, 300, and 450g of concentrate per kg daily milk production, during three experimental periods of 15 days each in a crossover design. Pasture and concentrate samples were collected and were analyzed for dry matter, crude protein, neutral detergent fiber, and acid detergent fiber. Milk production (kg d-1) was recorded daily, nitrous oxide (N2O), and emissions from excreta and daily CH4 production were calculated. Results were analyzed with the SAS MIXED procedure. Concentrate supplementation in tropical crossbred dairy cows did not improve milk yield but increased CH4 and N2O production (P < 0.0001) per cow as the concentrate increased in the diet; the Ym factor from the tropical region yielded less CH4 than the IPCC Ym model (P < 0.0001). In conclusion, the calculation of CH4 using specific emission factors for the tropical climate region is better than the IPCC default emission factors in order not to overestimate the CH4 emissions.(AU)

Effects of weather and other factors on milk production in the Churra dairy sheep breed

The objective of this study was to investigate the influence of meteorological and other factors on the quality and quantity of milk of the Spanish Churra sheep breed, based on an analysis of 359,808 milk controls from 9,904 ewes on 15 farms in 8 years. Daily milk yield (DMY), fat, protein, and lactose (%), and somatic cell count (SCC) data were obtained from monthly alternating milk controls. Mean, maximum, and minimum temperatures (T) (°C), mean relative humidity (RH) (%), wind speed (WS, m/s), mean solar radiation (SR, MJ/m2), and total rainfall (RF, mm) on the day before each milk control day were documented. Year, farm, number of lambing and stage of lactation, and all of the meteorological factors had asignificant (P < 0.0001) effect on DMY and milk quality. DMY and SCC differed among seasons (P < 0.001), and maximum DMY and minimum SCC occurred in spring, and minimum DMY and maximum SCC occurred in autumn. Fat, protein, and lactose content differed significantly (P < 0.001) among seasons, and fat and protein contents were highest in autumn. DMYwas highest in the second lambing of the ewe and steadily declined in subsequent lambings. SCC increased significantly from the first to the 10th lambing of the ewe. DMY, SCC, and fat content differed significantly (P < 0.001) among years. In conclusion, meteorological conditions had a significant effect on milk quality and production in Churra sheep conditions in a season-dependent manner such that factors such as temperature had the opposite effect on milk production in hot and cold seasons.(AU)

Effects of weather and other factors on milk production in the Churra dairy sheep breed

The objective of this study was to investigate the influence of meteorological and other factors on the quality and quantity of milk of the Spanish Churra sheep breed, based on an analysis of 359,808 milk controls from 9,904 ewes on 15 farms in 8 years. Daily milk yield (DMY), fat, protein, and lactose (%), and somatic cell count (SCC) data were obtained from monthly alternating milk controls. Mean, maximum, and minimum temperatures (T) (°C), mean relative humidity (RH) (%), wind speed (WS, m/s), mean solar radiation (SR, MJ/m2), and total rainfall (RF, mm) on the day before each milk control day were documented. Year, farm, number of lambing and stage of lactation, and all of the meteorological factors had asignificant (P < 0.0001) effect on DMY and milk quality. DMY and SCC differed among seasons (P < 0.001), and maximum DMY and minimum SCC occurred in spring, and minimum DMY and maximum SCC occurred in autumn. Fat, protein, and lactose content differed significantly (P < 0.001) among seasons, and fat and protein contents were highest in autumn. DMYwas highest in the second lambing of the ewe and steadily declined in subsequent lambings. SCC increased significantly from the first to the 10th lambing of the ewe. DMY, SCC, and fat content differed significantly (P < 0.001) among years. In conclusion, meteorological conditions had a significant effect on milk quality and production in Churra sheep conditions in a season-dependent manner such that factors such as temperature had the opposite effect on milk production in hot and cold seasons.

Concentrate supplementation on milk yield, methane and CO2 production in crossbred dairy cows grazing in tropical climate regions

The objective of this study was to evaluate the level of concentrate supplementation on the production and chemical composition of milk from 12 crossbred F1 dual-purpose cows (½ Bos taurus – ½ Bos indicus) and estimate the emission of CH4, N2O, and CO2 gases. The study included 12 crossbred F1 dual-purpose cows over 60 days of lactation. The cows grazed on 28% tropical native grassland and 72% Brachiaria spp. and Cynodon neumfluensis, supplemented with 0, 150, 300, and 450g of concentrate per kg daily milk production, during three experimental periods of 15 days each in a crossover design. Pasture and concentrate samples were collected and were analyzed for dry matter, crude protein, neutral detergent fiber, and acid detergent fiber. Milk production (kg d-1) was recorded daily, nitrous oxide (N2O), and emissions from excreta and daily CH4 production were calculated. Results were analyzed with the SAS MIXED procedure. Concentrate supplementation in tropical crossbred dairy cows did not improve milk yield but increased CH4 and N2O production (P < 0.0001) per cow as the concentrate increased in the diet; the Ym factor from the tropical region yielded less CH4 than the IPCC Ym model (P < 0.0001). In conclusion, the calculation of CH4 using specific emission factors for the tropical climate region is better than the IPCC default emission factors in order not to overestimate the CH4 emissions.

Worldwide Traceability of Antibiotic Residues from Livestock in Wastewater and Soil: A Systematic Review.

The use of antibiotics in animal production are widely used for disease treatment, health protection, and as growth promoters. Common antibiotics used in veterinary medicine are excreted and eliminated through the sewage system, contaminating water and soil with negative effects on agricultural activities. This systematic review focuses on the trend of research works on antibiotic residues, evaluating antibiotics used in livestock production and their excretion in animal products and in environmental matrices such as water and soil. Our database was composed of 165 articles, reporting the concentration of antibiotic residues found in the environment, livestock (cow, sheep, pig, horse, chicken, rabbit, goat), aquatic and terrestrial animal tissues, animal products (milk and eggs), wastewater, and soil. The documents were obtained from Asia, Africa, North America, South America, Europe, and Oceania. A descriptive analysis of antibiotic residues found worldwide was analyzed according to each of the variables used such as antibiotic family, name, concentration (% and mg/kg or ppm), and country and continent where the residue was found. The descriptive analysis was carried out using the "describe" function of psych package and pirate plots were drawn. According to our study, the main antibiotics used worldwide in animal production are sulfonamides, tetracyclines, quinolones, penicillin, and cephalosporins. At present, despite the trends of increased regulations on the use of antibiotics worldwide, antibiotics are still utilized in food animal production, and are present in water and soil, then, there is still the misuse of antibiotics in many countries. We need to become aware that antibiotic contamination is a global problem, and we are challenged to reduce and improve their use.

Production Performance, Nutrient Digestibility, and Milk Composition of Dairy Ewes Supplemented with Crushed Sunflower Seeds and Sunflower Seed Silage in Corn Silage-Based Diets.

This study determined production performance, nutrient digestibility, and milk composition of dairy ewes supplemented with crushed sunflower seeds (Helianthus annuus) and sunflower seed silage in corn silage-based diets. Six ewes were grouped in a double 3 × 3 Latin square design with three periods of 21 days. All treatments were based on ad libitum corn silage. Control diet was based on alfalfa hay (333 g/kg DM), sorghum grain (253 g/kg DM), triticale grain (200 g/kg DM), soybean meal (167 g /kg DM), and vitamin and mineral premix (47 g/kg DM). Sunflower seeds (SF) and sunflower seed silage (SFS) treatments consisted of alfalfa hay (333 g/kg DM), sorghum grain (267 g/kg DM), triticale grain (100 g/kg DM), soybean meal (167 g /kg DM), SF or SFS (87 g/kg DM) and vitamin and mineral premix (47 g/kg DM). Compared to control, SF and SFS increased intake and digestibility of fiber components, such as neutral detergent fiber (NDF) and acid detergent fiber (ADF). Body weight, nitrogen balance, milk yield, milk fat yield, milk protein yield, lactose yield and milk urea N were similar between treatments. Overall, results demonstrated that crushed sunflower seeds and ensiled seeds do not change significantly productive parameters of dairy sheep.

Physico-Chemical, Sensory and Texture Properties of an Aged Mexican Manchego-Style Cheese Produced from Hair Sheep Milk.

The objective of this study was to evaluate the physicochemical and texture changes of the Manchego-style cheese produced from hair sheep (Pelibuey) throughout 180 days of ripening, as well as consumer's acceptance. Cheese pH was constant from 1 to 180 days of ripening. Moisture, water activity, fat, elasticity and hardness decreased from day 1 to day 180, while protein, trichloroacetic acid-soluble N and free amino acid increased. Cheese lightness decreased as ripening time increased, while elasticity and hardness decreased. Principal Component Analysis was useful in discriminating cheeses according to their physicochemical composition and that allowed cheeses to be classified in two groups according to their ripening time and this resulted in those with less than 60 days and those with more than 90 days of ripening. Compared with cheeses ripened at 1 and 90 days, aged cheeses at 180 days reduced scores for appearance, color, odor, taste, texture and overall acceptance. Overall, Manchego-style cheeses from hair sheep had the usual ripened-cheese physicochemical changes.