Category Archives: Animal Science Journal

Modification of dietary rumen degradable starch content by chemical processing of feed ingredients: A meta‐analysis

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Abstract

The efficiency of starch utilization in ruminant feed can be enhanced by reducing the degradation of starch in the rumen. Chemical processing of feed ingredients may modify such ruminal starch degradation. This study aimed to evaluate the chemical processing of ruminant feed ingredients on rumen degradable starch (RDS) and starch degradation kinetics in the rumen. A database was constructed from a total of 34 articles, consisted of 100 observations. The articles were searched and identified from the Scopus platform. Data were analyzed by using the fixed effect model. The types of chemical processing in this study included sodium hydroxide, ammonia, potassium aluminum, urea, formaldehyde, and organic acid. Results indicated that chemical processing significantly reduced the RDS content (p < 0.001) and the immediately soluble fraction (p < 0.001) and increased the value of slowly degradable fraction (p < 0.001) and starch absorption in the small intestine (p < 0.01). Formaldehyde was particularly effective to decrease the RDS (p < 0.05). The RDS contents in corn and wheat were reduced by the chemical processing (p < 0.05), but not with that of barley. It can be concluded that chemical processing is effective in reducing starch degradation of ruminant feeds and may enhance its utilization by ruminants.

Egg‐laying capacity of parent flock geese at different stocking densities

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Abstract

This article presents the results of studies aimed at establishing the optimal stocking density of purebred and hybrid geese of the parent flock, taking into account the indicators of their live weight and egg production. When conducting research, the stocking density of geese was established depending on the breed and shape. Different stocking densities of geese in groups were achieved due to their different numbers in groups: Kuban 1.2; 1.5; 1.8 birds/m2, large gray 0.9; 1.2; 1.5 birds/m2, hybrid bird 1.0; 1.3; 1.5 birds/m2. It was revealed on the basis of the analysis of the productive qualities of adult geese that the optimal planting density of the Kuban geese is 1.8 heads/m2, large sulfur = 0.9, hybrid = 1.3. The safety of geese at a given stocking density ensured an increase in the safety of geese of the Kuban breed by 95.3%, large gray = 94.0%, hybrid = 97.0%. The live weight of Kuban geese increased by 0.9%, large gray geese = 0.10, hybrids = 1.2, egg production by 0.6%, 2.2% and 0.5%, respectively.

Prediction of methane emissions from fattening cattle using the methane‐to‐carbon dioxide ratio

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Abstract

This study aimed to develop a prediction equation for methane (CH4) emissions from fattening cattle based on the CH4/carbon dioxide (CO2) ratio and validate the predictive ability of the developed equation. The prediction equation was developed using the CH4/CO2 ratio combined with oxygen consumption and respiratory quotient estimations that were theoretically calculated from the relation between gas emissions and energy metabolism. To validate the prediction equation, gas measurements in the headboxes were conducted using eight Japanese Black steers. The predictive ability of the developed equation was compared with that of two previously reported equations. As a result, the developed and reported equations had significant (P < 0.01) linear relationships between the observed and predicted CH4 emissions. Notably, only the developed equation had a significant (P < 0.01) linear relationship between the observed and predicted CH4 emissions when expressed per unit of dry matter intake. The results suggest that the developed prediction equation has a higher predictive ability than previously reported equations, particularly in evaluating the efficiency of CH4 emissions. Although further validation is required, the equation developed in this study can be a valuable tool for on-farm estimations of individual CH4 emissions from fattening cattle.

Menthol application on healthy and inflamed goat udders changes antimicrobial components in milk

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Abstract

Mammary glands with mastitis are usually treated with antibiotics in combination with anti-inflammatory drug application on the udder skin. Menthol is an anti-inflammatory drug. The aim of the present study was to investigate the effect of surface application of menthol on goat udders on the production of antimicrobial components in milk. Goats (5 Shiba and 11 Tokara goats) were subjected to menthol application to the udder under both healthy and inflammatory conditions. An intramammary infusion of lipopolysaccharides was carried out to induce inflammatory conditions in the udder. Milk samples were collected to determine somatic cell count (SCC) and sodium ion (Na+), antimicrobial component and cytokine concentrations. In healthy udders, menthol application increased the concentration of antimicrobial components (S100A7 and S100A8), but not in the control. In the inflamed udder, antimicrobial component (lactoferrin, S100A7, and S100A8) and inflammatory cytokine (IL-1β) concentrations were higher in the menthol group than in the control group. These results suggest that menthol application on udders augments the antimicrobial component concentration in the mammary gland under both healthy and inflammatory conditions.

Genome‐wide detection of changes in allelic frequency in Landrace pigs selected for resistance to mycoplasma pneumonia of swine

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Abstract

Closed-pig line breeding could change the genetic structure at a genome-wide scale because of the selection in a pig breeding population. We investigated the changes in population structure among generations at a genome-wide scale and the selected loci across the genome by comparing the observed and expected allele frequency changes in mycoplasma pneumonia of swine (MPS)-selected pigs. Eight hundred and seventy-four Landrace pigs, selected for MPS resistance without reducing average daily gain over five generations, had 37,299 single nucleotide polymorphisms (SNPs) and were used for genomic analyses. Regarding population structure, individuals in the first generation were the most widely distributed and then converged into a specific group, as they were selected over five generations. For allele frequency changes, 96 and 14 SNPs had higher allele frequency changes than the 99.9% and 99.99% thresholds of the expected changes, respectively. These SNPs were evenly spread across the genome, and a few of these selected regions overlapped with previously detected quantitative trait loci for MPS and immune-related traits. Our results indicated that the considerable changes in allele frequency were identified in many regions across the genome by closed-pig line breeding based on estimated breeding value.

Use of a commercial indoor positioning system for monitoring resting time and moving distance in group‐housed dairy calves

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Abstract

To assess the usefulness of a commercially available indoor positioning system for monitoring the resting time and moving distance in group-housed dairy calves as indicators of their health status, five dairy calves were housed in a free barn, and their coordinate was recorded. The mean displacement (cm/s) within a minute showed a double-mixture distribution. Actual observations revealed that the minutes in the first distribution with shorter displacement were mostly the time that the calves spent lying. To predict the daily lying time and moving distance, a mixed distribution was divided at a threshold value. The mean sensitivity (the proportion of total minutes predicted correctly as lying, in total minutes observed lying) was more than 92%. The daily fluctuation in lying time correlated well with the actual lying time (r = 0.758, p < 0.01). The range of fluctuations was 740–1308 min/day and 724–1269 m/day for daily lying time and moving distance, respectively. The rectal temperature was correlated with daily lying time (r = 0.441, p < 0.001) and distance moved (r = 0.483, p < 0.001). The indoor positioning system can be a useful tool for early illness detection in calves before the onset of symptoms in group-housing systems.

Rumen microbial composition associated with the non‐glucogenic to glucogenic short‐chain fatty acids ratio in Holstein cows

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Abstract

This study aimed to determine the physiological features and rumen microbial composition associated with the non-glucogenic-to-glucogenic short-chain fatty acids ratio (NGR). Holstein cows were housed in a free-stall barn with an automatic milking system and fed a partially mixed ration. Physiological and microbial analyses were performed on 66 datasets collected from 66 cows (50–250 days in milk). NGR was positively correlated with ruminal pH, relative abundances of protozoa and fungi, methane conversion factor, methane intensity, plasma lipids, parity, and milk fat, and negatively correlated with total short-chain fatty acids. To highlight the differences in bacterial and archaeal compositions between NGRs, low-NGR cows (N = 22) were compared with medium-NGR (N = 22) and high-NGR (N = 22) cows. The low-NGR group was characterized by a lower abundance of Methanobrevibacter and a higher abundance of operational taxonomic units belonging to the lactate-producing, such as Intestinibaculum, Kandleria, and Dialister, and the succinate-producing Prevotella. Our findings indicate that NGR affects the methane conversion factor, methane intensity, and blood and milk compositions. Low NGR is associated with a higher abundance of lactate- and succinate-producing bacteria and lower abundances of protozoa, fungi, and Methanobrevibacter.

Comparison of carcass traits and nutritional profile in two different broiler‐type duck lines

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Cherry Valley ducks (CVDs) and White Kaiya ducks (WKDs) are judged to be fast- and slow-growing lines, respectively. To investigate the carcass traits and nutritional profile at their marketable ages, 12 birds (38 days for CVDs, n = 6; 56 days for WKDs, n = 6) were randomly selected and slaughtered. Indicators such as breast muscle weight, shear force, and proximate composition were comprehensively detected. Although the carcass and breast muscle weight in WKDs were significantly lower, remarkably higher intramuscular fat and tenderness and less moisture content were observed in WKDs. Besides, WKDs contained higher contents of Cu, Zn, and Ca, whereas CVDs contained higher leucine (Leu) and histidine (His) compositions (P < 0.01). Moreover, higher monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs) along with lower saturated fatty acids (SFAs) were detected in WKDs (P < 0.01). Taken together, despite light carcass and breast muscle weight, WKDs had advantages in nutritional compositions except for amino acid constituents, including intramuscular fat, MUFAs, and PUFAs, as well as Cu, Zn, and Ca. These data would not only provide genetic resources for breeding new duck lines but also offer a useful reference for making decisions on high-nutrient meat consumption.

L‐histidine inhibits the heat‐induced gelation of actomyosin in a low ionic strength solution

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Abstract

The heat-induced gelation of actomyosin plays a key role in meat processing. Our previous study showed that L-histidine could affect the characteristics of a heat-induced gel of myosin on a low ionic strength. To apply the specific effect of L-histidine to meat processing, the heat-induced gel properties of actomyosin in the presence of L-histidine were investigated. Actomyosin in a low ionic strength solution containing L-histidine did not form a gel upon heating. The dynamic rheological properties of actomyosin in low ionic strength solutions were distinct depending on the presence or absence of L-histidine. Electron microscopy showed that, heated at 50°C, actomyosin in a low ionic strength solution containing L-histidine remained a filamentous structure. The surface hydrophobicity of actomyosin was stable up to 50°C in a low ionic strength solution containing L-histidine. In conclusion, L-histidine might suppress the aggregation of actomyosin and inhibit heat-induced gelation in a low ionic strength solution.

L‐Citrulline: A novel hypothermic amino acid promoting thermotolerance in heat‐exposed chickens

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With global warming becoming of increasing concern, poultry farms are experiencing a concomitant increase in heat stress. Chickens are very sensitive to high ambient temperature (HT), so the development of novel nutrients that will help deal with the challenge posed by heat stress is vital. We revealed that L-citrulline (L-Cit) can reduce body temperature in chickens. Orally administered L-Cit solution has been found to provide heat tolerance in chickens and to result in reduced food intake. Heat exposure and oral administration of L-Cit led to increased levels of plasma insulin, whereas heat stress led to a decline in plasma thyroxine. Dietary administration of L-Cit was also shown to be effective to reduce heat stress in broiler chickens. Moreover, L-Cit was found to be metabolized in the liver within 1 h of its administration, and in L-Cit-treated broiler chicks, the Cit-Arginine cycle and the Krebs cycle were found to be active. L-Cit has not yet been approved for inclusion in the poultry diet, so it is important to find alternative sources of L-Cit. Taken together, these findings suggest that L-Cit may serve as an important novel nutrient with the ability to produce heat tolerance in chickens under HT.