Udder Quality Research Articles

INFLUENCE OF MORPHOLOGICAL FEATURES OF COWS’ UDDER TEATS ON THE PROCESS OF MACHINE MILKING

Machine milking technology requires a strict selection of cows, because different factors influence its efficiency: physiological characteristics of animals, technical characteristics of milking plants, etc. In this connection, the purpose of our research was to study udder quality and to establish the influence of teat morphological features on the process of machine milking. It was found that 75% of the herd had cylindrical teat shape, which contributed to complete udder emptying, there was no teat canal
 overcompression in the upper part, the cows did not show anxiety. At the same time, animals with funnel-shaped and conical udders were identified (15.9 and 9.1%, respectively).
 When milking these cows, the teat canal in the upper part was clamped by the rigid edges of the teat rubber, which slowed down the process of milking. When milking these animals, it is recommended to use teat rubbers with soft edges of the head, which can increase the average and maximum milk flow rates of cows by 12.5 and 7.5% respectively and relative milk yield by 3.3 percentage points.

Genetic evaluation of weaning weight and udder score in Nellore cattle

The aim of this study was to estimate genetic parameters for weaning weight (WW) and udder score (US) of 186,151 Nellore animals raised in extensive systems. The (co)variance components and estimated breeding values (EBVs) were obtained by two-trait analyses using Bayesian inference. The maternal effect (ME) was expressed as the maternal additive genetic variance of the calf's weaning weight (WW). The direct heritabilities were 0.13 ± 0.012 and 0.23 ± 0.012 for WW and US, respectively. The maternal heritability was 0.11 ± 0.012 for WW. The genetic correlations between WW and US (0.48 ± 0.053), WW and ME (0.41 ± 0.067), and US and ME (0.31 ± 0.041) were positive and moderate. Cows with maternal udder scores (US_M) 3 and 4 showed higher EBVs for ME (2.58 ± 0.070 and 2.88 ± 0.214, respectively) and their progeny had higher EBVs for WW (4.58 ± 0.058 and 5.07 ± 0.168) and US (0.20 ± 0.001 and 0.26 ± 0.005). The genetic trends demonstrate genetic progress in the selection program over the years, with values of 0.19 kg and 0.01 points for WW and US, respectively. The genetic trend in ME was 0.04 kg for WW. In addition, a positive genetic correlation was observed between these traits, as well between the traits and ME, i.e., selection would result in positive genetic gains. The use of US_M may help improve body weight and udder quality in the progeny. Furthermore, the trends indicate that the selection adopted on the farms has been effective in promoting genetic progress.

Species composition of microbiota of cows udder and raw milk quality at mastitis

To increase the productivity of cows and improve the nutritional and sanitary-technological qualities of milk is one of the most important tasks in the development of dairy farming in all countries of the world. The cause of degradation of these parameters is such a widespread disease of cows as mastitis. The social significance of mastitis is manifested in the fact that the causative agents of mastitis in cows can cause disease in humans. Since streptococci and staphylococci play a leading role in mastitis, they are the most common in milk. Studies have shown that udder disease in cows with mastitis at the beginning of lactation has a certain seasonal nature and its main peaks occur in March-May and September-November. During these months, from 2.5% to 4.1% of cows from the total number of livestock of the farm were found to have mastitis. Physiochemical features of milk from the cows with mastitis were an increase in the number of somatic cells to 1,500,000/cm3, increase of milk pH to 7.3, caused by the breakdown of milk proteins into ammonia, the increase in milk electrical conductivity to 5.92-7.54 mS/cm, associated with the entry of sodium and chlorine ions from the blood into the milk. In studies of cows with mastitis, 16 species of bacteria were isolated from the secretion of the udder. In monoculture, the microflora, that was found in 30.5% of cows, consisted of E. coli, St. epidermidis, C. freundi, Sh. Dysentery, St. aureus, St. hyicus spp. Chromogenes, Str. Agalactiae, St. lentus, and St. intermediate. In 69.5% of cows with mastitis, the microflora was found in various associations. The most common associations of bacteria were St. epidermidis + St. aureus + Str. agalactiae + Str. haemolyticus; E. coli + Str. agalactiae; Str. agalactiae + St. epidermidis; St. epidermidis + St. aureus + Str. agalactiae. We developed a method for diagnosing mastitis in cows, which was to diagnose the disease at early stage of inflammation of the mammary glands by studying the composition of the milk the examined lobe of the udder.

Long Term Benefits on Social Behaviour after Early Life Socialization of Piglets

Simple SummaryPig welfare is a societal concern, partly due to the intensive rearing conditions. One welfare concern is aggression between newly regrouped pigs. Aggression at weaning is reduced by putting several groups of piglets together when young; termed socialization. Information is missing about how socialization affects sow health and if the behavioural changes in piglets are long-lasting. We aimed to address these questions by studying sow udder quality and pig behaviour and growth in socialized and control groups. Pigs were socialized by either joining two litters (32 sows; 16 groups) at 14 days of age or not joining them (33 sows). At weaning, the sows of socialized groups had more udder damage than the controls. Socialized piglets had double the amount of bite injuries (skin lesions) than controls the day after socialization, but had 19% fewer skin lesions at regrouping at eight weeks old when injuries are more numerous and severe. At 11 weeks old, there was no difference between the groups. In a test for aggressiveness, socialized pigs attacked more often and quicker, showing greater confidence in agonistic skills. Socialization means additional work for farmers and may cause more udder damage, but has beneficial effects for pig behaviour and welfare at later regrouping.Early life socialization of piglets has been shown to reduce piglet aggression at weaning, but information on sow health and long-term benefits is lacking. We aimed to assess how socialization impacts sow udder quality and long-term pig behaviour and growth. At two weeks of age, 65 litters either experienced socialization with one other litter (SOC) or did not (control; CON). Sows (housed in farrowing crates) were scored for teat damage and piglets were observed for aggressive behaviour (resident-intruder test) and growth and skin lesions up to 11 weeks under conventional farm conditions (including weaning and regrouping). At weaning, SOC sows had more teat damage than CON sows (p = 0.04). SOC piglets had double the number of lesions 24 h post-socialization compared to the control (19 versus 8; p < 0.001). In the resident-intruder test, more SOC pigs attacked the intruder (SOC 78%; CON 66%; p < 0.01), and attacked more quickly (p = 0.01). During regrouping (week 8), SOC pigs had 19% fewer lesions (SOC 68; CON 84; p < 0.05), but three weeks later, groups did not differ. Growth was unaffected by treatment. Overall, socialized piglets seem to be equipped with greater confidence or agonistic skills, leading to fewer injuries from fighting up to at least six weeks after socialization.

Heritability of udder morphology and colostrum quality traits in swine.

The heritability of udder quality traits, defined as morphology and colostrum IgG concentration at farrowing, was estimated together with the genetic and phenotypic correlations of these traits with other production and reproduction criteria. Udder morphology traits were recorded in 988 Meidam sows and colostrum samples were collected from 528 sows. Teat length, teat diameter (DIA), interteat distance within the same row (SAMER), and teat distance from the abdominal midline (AML) were recorded to the nearest millimeter. For each sow, a record was also made of udder development score (DEV), the proportion of teats oriented perpendicular to the udder, and the proportion of nonfunctional teats. Colostrum IgG concentration was estimated with a Brix refractometer. Heritability of udder morphology traits varied from high ( = 0.46 for teat length and = 0.56 for DIA) to moderate ( = 0.37 for SAMER, = 0.22 for AML, = 0.25 for DEV, = 0.3 for the proportion of nonfunctional teats, = 0.1 for the proportion of teats oriented perpendicular to the udder, and = 0.35 for colostrum IgG concentration). The SAMER was negatively genetically correlated with the number of stillborns (genetic correlation [] = -0.48) and positively genetically correlated with the number of piglets born alive ( = 0.69), with the opposite for the trait AML ( = -0.40 for number of piglets born alive and = 0.40 for stillborns). The highest genetic correlation with productive traits was estimated between AML and ADG during rearing ( = 0.42), although this had a negative phenotypic correlation (; -0.11). Teat length was also moderately correlated with ADG ( = 0.27). Backfat thickness at 100 kg was positively correlated with DIA and the total number of teats present in both rows ( = 0.28 and = 0.36, respectively) and negatively correlated only with DEV ( = -0.22). The same results were found for the phenotypic correlation between backfat thickness at end of test and the total number of teats present in both rows ( = 0.03). Udder quality traits can be included in the breeding goal and appropriately weighted with other important traits in the breeding objectives to enhance maternal performance.

Genetic associations between maternal traits and aggressive behaviour in Large White sows

The present study examined the possibilities and consequences of selecting pigs for reduced aggression and desirable maternal behaviour. Data were recorded from 798 purebred Large White gilts, with an age of 217±17.7 (mean±SD) days, which were observed at mixing with unfamiliar conspecifics. The reaction of the sows towards separation from their litter was assessed for 2022 litters from 848 Large White sows. Sows’ performance during their time in the farrowing unit was scored based on the traits farrowing behaviour (i.e. need of birth assistance), rearing performance (i.e. litter quality at day 10 postpartum (pp)), usability (i.e. additional labour input during lactation period e.g. for treatments) and udder quality of the sow (i.e. udder attachment). For agonistic behaviour, traits heritabilities of h2=0.11±0.04 to h2=0.28±0.06 were estimated. For the sow’s reaction towards separation from her litter low heritabilities were found (h2=0.03±0.03 for separation test on day 1 pp and h2=0.02±0.03 for separation test on day 10 pp). Heritabilities for lactating sow’s performance (farrowing behaviour, rearing performance, usability of the sow and udder quality) in the farrowing unit ranged from h2=0.03±0.02 to h2=0.19±0.03. Due to these results it can be assumed that selection for these traits, for example, for udder quality or reduced aggression, is possible. Antagonistic associations were found between separation test on day 1 pp and different measures of aggressiveness (rg=−0.22±0.26 aggressive attack and rg=−0.41±0.33 reciprocal fighting). Future studies should determine economic as well as welfare-related values of these traits in order to decide whether selection for these traits will be reasonable.

Udder quality is moderately heritable in Hereford cattle (2014)

Udder quality is an important factor related to cow longevity and calf performance. Cows with tighter udder suspension and smaller teats tend to have greater longevity. When cows stay in the herd longer, fewer replacement heifers need to be developed to maintain herd size. Pendulous, poorly suspended udders and large teats are difficult for newborn calves to nurse, and additional labor might be required to assist those calves. Cows with poor udder quality can have increased calf mortality because the calf struggles to nurse and consumes colostrum later. Because many beef producers sell calves by the pound at weaning, poor udder quality can have a negative impact on profit. The dairy industry has selected for udder quality for many years. Udder traits are generally moderately heritable in dairy cattle, but limited research has been done in beef cattle. Beef producers would benefit from genetic selection tools for improving udder quality, especially for herds where udder quality affects calf performance. Our objective was to estimate the heritabilities and genetic correlations for udder quality traits in Hereford cattle. American Hereford Association members have been reporting udder scores for a number of years. The American Hereford Association initially began collecting an overall udder score, which combined all udder characteristics into a single score. In 2008, the Beef Improvement Federation developed udder scoring guidelines, including scores for both udder suspension and teat size. By August 2008, the American Hereford Association began using these new guidelines and collected udder suspension and teat size scores instead of the overall scores. All scores were recorded on a 1 to 9 scale, with scores of 9 considered ideal. Cows are scored at calving and could have multiple records throughout their lifetimes.

Genetic analysis of gain from birth to weaning, milk production, and udder conformation in Line 1 Hereford cattle1,2

The objective of this research was to partition phenotypic variation in calf gain from birth to weaning, and milk production measured, by the weigh-suckle-weigh method, and udder score of cows into genetic and nongenetic components. Data were from the Line 1 Hereford population maintained by USDA-ARS at Miles City, MT, and included observations of pre-weaning gain (n = 6,835) from 2,172 dams, milk production (n = 692) from 403 cows, and udder score (n = 1,686) from 622 cows. Data were analyzed using a Gibbs sampler for multiple-trait animal models. Results are reported as means +/- SD derived from the posterior distributions of parameter estimates. Mean estimates of the phenotypic variance of preweaning gain, milk production, and udder score were 476.3 kg2, 8.88 kg2, and 1.89 (1 to 9 scale), respectively. Estimates of phenotypic correlations between preweaning gain and milk production, preweaning gain and udder score, and milk production and udder score were 0.37 +/- 0.04, - 0.07 +/- 0.04, and - 0.09 +/- 0.05, respectively. Estimates of heritability for direct and maternal preweaning gain, milk production, and udder score were 0.13 +/- 0.03, 0.25 +/- 0.04, 0.25 +/- 0.06, and 0.23 +/- 0.05, respectively. Genetic correlations of milk production with maternal preweaning gain and udder score were estimated as 0.80 +/- 0.08 and - 0.36 +/- 0.16, respectively. Posterior distributions of the other genetic correlations all contained 0.00 within the respective 90% probability density posterior intervals. Estimates of repeatability of maternal preweaning gain, milk production, and udder score were 0.43 +/- 0.03, 0.39 +/- 0.05, and 0.34 +/- 0.03, respectively. Breeding value for maternal gain from birth to weaning was highly predictive of breeding value for milk production. Direct measurement of milk production to use in genetic improvement may not be justified because it is difficult to measure, and selection based on the breeding value for maternal preweaning gain may be nearly as effective in changing milk production as direct selection. A potentially undesirable consequence of selection to increase milk production is the degradation of udder quality. However, this correlation is not so strong as to preclude simultaneous improvement of milk production and udder quality using appropriate predicted breeding values for each trait.

Genetics of locomotion

The objectives of this study were to estimate the heritability of locomotion score and estimate the genetic and phenotypic correlations of locomotion score with milk production (150-day milk), body condition score (BCS), and selected conformation traits. Data were collected from 26 herds that were visited in October and December of 1997. During those two visits all lactating cows were assigned scores for locomotion and BCS. Locomotion was scored on a scale from 1 (excellent) to 5 (severely lame). Data consisted of 5774 records from 3298 cows. The heritability of locomotion was low. The phenotypic correlations of locomotion score with 150-day milk and the conformation traits were low. BCS and 150-day milk had moderate negative correlations with locomotion. Cows with higher BCS and higher 150-day milk had genetically better locomotion. Locomotion score had high genetic correlations with feet and legs, foot angle, and rear leg set. Udder traits had favorable moderate genetic correlations with locomotion. Cows with a higher feet and legs score, steeper foot angle, and straighter legs also had genetically significant better locomotion. Cows with higher rear udder attachments, longer front udder attachment, and increased udder quality had more favorable locomotion.

Genetic Parameters for Body Condition Score and its Relationship with Type and Production Traits in Swiss Holsteins

The objectives of this study were to estimate the genetic and environmental parameters between body condition score (BCS) and 27 conformation and 3 production traits in Swiss Holstein cattle. The dataset consisted of 31,500 first-lactation cows, which were daughters of 545 sires in 1867 herds. Bivariate sire models with relationships among sires were used to estimate parameters. Least squares means for BCS by lactation stage show that cows lose BCS up to 5 mo after calving and gain BCS prior to the next calving. Regression models showed that an increase in age and percentage of Holstein genes results in an increase and decrease in BCS, respectively. Heritability (h2) was 0.24 for BCS score, which indicates good potential for selection. Sire estimated breeding values for BCS ranged from −0.46 to +0.51 units. Heritabilities ranged from 0.08 (heel depth) to 0.46 (rump width) for type traits and 0.23 to 0.29 for yield traits. Genetic correlations of BCS with 8 conformation traits were significant; stature (0.28), heart girth (0.21), strength (0.17), loin (−0.39), body capacity (0.19), dairy character (−0.35), udder quality (−0.42), and teat position rear (−0.33). Milk production and body condition have an unfavorable genetic correlation (−0.12 to −0.17). These results show that selection for good body condition, body conformation, and optimal milk production is possible and their genetic associations reported here will be useful for designing Swiss breeding goals.

Environmental and genetic effects on udder characteristics and milk production in Damascus goats

A total of 829 records collected at three experimental farms (ARI, Athalassa and Orites) from 1979 to 1982 was studied for environmental and genetic influences on udder characteristics and milk production in Damascus goats. All udder traits were recorded following weaning (70 ± 3 days) concurrently with the first milk recording (7± 3 days after weaning). Most traits were significantly rekated to flock except milking ease, test-day milk and 90-day milk yield. Year effects were small ( P>0.05) for udder depth, udder floor, udder quality, milking ease and total milk yield. Season significantly affected udder depth and total milk production. Lactation number had a significant effect on all traits except udder floor, udder quality and milking ease. Udder floor was significantly related to milk production, while udder quality and milking ease had no effect. Most heritability estimates, except for udder quality (0.03 ± 0.09), were moderate to high. Test-day milk yield (0.31 ± 0.11) and udder floor (0.22 ± 0.11) had moderately low heritability estimates, while teat length and diameter were highly heritable (from 0.55 ± 0.13 to 0.77 ± 0.14). Heritability estimates for 90-day and total milk production were 0.52 ± 0.13 and 0.46 ± 0.12, respectively. Udder circumference and udder depth (traits that describe the volume of the udder) were moderately heritable. Genetic association of udder circumference before milking with milk production was moderately high. Phenotypic correlation among the above traits was positive and also moderately high.

Relationships of Udder Conformation with Labor and Machine Inputs to Milk Harvest in Dairy Cattle

Udder type and physical measurements of udders and teats of Holsteins and Jerseys were studied to determine associations with labor and milking machine inputs to harvest milk. Among udder traits evaluated in type classification, only udder quality and udder support were associated with labor inputs to milking. Among Holsteins, both udder traits were associated slightly with labor inputs to milking, with udder quality the better predictor. Udder quality of Holsteins accounted for part of the increased labor and machine inputs to milking due to age-parity of survivors.Cows with larger udder (Holstein) and rear teat measurements (both breeds) required more labor and machine inputs to milking than cows having small mammary dimensions. Postmilking dimensions of the udder were associated most closely with labor and machine inputs.Results support the contention by dairymen that less desirable udder conformation means increased cost of milk harvest. Selection for more desirable udder conformation should decrease milking costs slowly.

Relationships among Udder Characteristics, Milk Yield, and Nonyield Traits

A total of 1604 udder measurements of the area bounded by the four teats was collected on 147 cows to determine relationships among udder area, indices of udder collapsibility, milk yield, rates of milk flow, California Mastitis Test scores, persistency of lactation, and visual appraisal of udder conformation. Direct measurements of the udder were highly repeatable both within and among lactations. Indices of udder collapsibility were not as repeatable. Correlations among udder measurements were large and positive. Milk yield on the day of measure was highly and positively correlated with udder measurements, but correlations with mature equivalent milk yield were lower. Correlations among udder measurements, rates of milk flow, persistency of lactation, and many traits of udder conformation were small. Larger udders were associated generally with higher mastitis test scores, with deeper udders that were more bulgy in front and looser in rear and with flatter udder floors. Indices of udder collapsibility were unrelated to visual appraisal of udder quality.

Genetic and Phenotypic Relationships Among Type Traits in Holstein-Friesian Cattle

Official scorecard and descriptive type classification data recorded by the Holstein-Friesian Association of America from 1967 to 1971 were evaluated to determine heritabilities of and phenotypic and genetic correlations among various type traits. First classification scores of 336,253 cows were used to develop age correction factors for final score, final classification, general appearance, dairy character, body capacity, and mammary system. Descriptive traits were not age adjusted. Covariances and variances derived from an intraherd analysis of daughter-dam type scores were used to determine heritabilities and genetic correlations. Each daughter-dam pair was restricted such that no more than 1 yr difference in age existed at the time of classification. A total of 30,715 pairs was used. Heritability estimates for scorecard components were moderate, ranging from .19 for dairy character to .31 for final score. Estimates for descriptive traits were more variable, ranging from 0 for udder quality expressed as a bionominal (desirable-undesirable) to .51 for stature. Standard errors for all estimates were .01. Most genetic correlations among type traits were positive and ranged from −.17±.22 between udder quality (expressed as desirable-undesirable) and dairy character to 1.01 ±.08 between final score and final classification. Phenotypic correlations were generally smaller than genetic correlations.

Sire-Son Relationships for Type in Holstein-Friesian Cattle

Official classification scores of 336,253 registered Holstein cows recorded from 1 January 1967 through 30 September 1971 were utilized to develop daughter average progeny test information on bulls for final score, the four scorecard traits (general appearance, dairy character, body capacity, and mammary system), and 12 descriptive traits in the official Holstein classification program. Only the first available classification score on each cow was used. Age correction factors were derived for final score and for the scorecard traits, and all traits were adjusted to a 5-yr-old mature base. A total of 1,872 sire-son pairs was included. Regressions of son progeny test on sire progeny average were positive for all traits. Regressions generally were greater than .20 for final score, scorecard traits, and some descriptive traits including stature, back, rump, fore udder, rear udder, udder support, and teat placement. They were less than .20 for head, front end, hind legs, feet, and udder quality. Regressions of nonartificial insemination sons on artificial insemination sires were larger than regressions of artificial insemination sons on artificial insemination sires. Regressions of nonartificial insemination and artificial insemination sons on nonartificial insemination sires were erratic and were not consistent with overall regressions. For progeny averages from sires with varying numbers of sons, final score and scorecard traits along with stature, head, rump, hind legs, fore udder, and rear udder had received considerable emphasis in selection of sires of sons.

Effects of Age, Herd, and Herd Status on Classification Scores of Jersey Cattle

Classification was arranged for herds belonging to the official Jersey program concurrently with classification for Jersey research herds. Herds were categorized as official, registered research and grade research. Cattle were also grouped as 2 year olds, 3 to 4 year olds and 5 year olds.Differences for herd status were significant (P<.05) for all type traits except stature, breed character, feet and legs and fore udder. Research cattle scored higher only in dairy character and udder quality. Differences between registered research and grade research cattle were not significant.Differences for age were significant for all traits except feet and legs, mammary and rear udder. Five year-olds scored highest in final score, general appearance, stature, breed character, back and rump, and chest and barrel. The traits relating to mammary system were scored higher on younger cows.For final score, herds accounted for 9.6 and sires 10.1% of the variance. Heritabilities ranged from .19 for feet and legs to .68 for stature.Indexes comparing sires’ daughters to contemporaries had correlations below .90 with other indexes. Adjusting for number of daughters did not greatly alter correlations.