Teat Characteristics Research Articles

High-precision scanning system for complete 3D goat udder and teat imaging, and analysis of morphological traits

Currently, udder scoring for goat udder phenotyping in France is made by a specialized technician trained to score 5 traits for the udder and 4 for teats, only one of which being measured (teat length). It is a hard work in big flocks, and only done one time in the life of goats. Recent works underlined a clear degradation of udder/teat shape with parity and an increasing proportion of morphological and functional unbalance of udders. Thus, for improved genetic selection, we must increase the number and quality of quantitative udder traits measured throughout the productive lifespan of dairy goats. To achieve this goal, we aimed to design a 3D Scanner device to scan the entire udder and to produce high definition numeric images. The device developed is easy to transport in a van and consists of a portable corridor cage in which the goats enter freely. Goats are then blocked less than 2 min while the images were taken. We used 4 Intel Realsense depth D415 cameras mounted on a mobile trolley situated 60 cm under and on the two sides of the cage and sliding from the front to the back of the animal in 10 s. The D415 has a baseline of 55 mm which allows the depth error to be less than 2% at 2 m. The device has an auto calibration internal software that ensure good evaluation of distances with one-millimeter depth precision at 50 cm. The reconstruction of the 3D Image from these 4 sources was done by the RecFusion® software. The image resolution obtained is 1280 * 720 pixels and real-time scene capture is done at up to 90 frames per second (900 images/camera/run/goat). The size of voxel generated was 2 mm. The first prototype was tested on 260 goats of different parity and udder shape and produced well-defined 3D images on which we can measure dimensions with Metrux2α® software after manual positioning of references points. The first validation steps wad done on a soccer ball and on 10 goats for comparison of manual scoring and Image analysis. Machine learning algorithms are currently being developed for the purpose of automatic measurement on these images. The actual precision of the automatic measurement will be assessed following the completion of this final phase. Nevertheless, this scanner shows great promise for future implementation within the goat selection scheme, as it enables swift, objective, and quantitative evaluation of udder and teat characteristics.

Ewe udder and teat traits as potential selection criteria for improvement of Merino lamb survival and growth

Neonatal lamb mortality is a major economic and welfare issue for Australian sheep producers. The contribution of udder and teat traits of the dam to the survival and subsequent growth of the lamb is relatively unknown. This study aimed to estimate phenotypic and genetic parameters associated with objectively measured and visually scored udder and teat traits in Australian Merino sheep, and to evaluate the impacts of udder and teat traits of the dam on survival and growth of their lambs to weaning. Ewes from the New England Merino Lifetime Productivity flock (n = 1341 ewes) were assessed for udder and teat traits, and phenotypic and genetic parameters for individual traits and relationships among them were estimated using linear mixed models. Odds ratios were calculated to investigate the influence of udder soundness on lamb mortality. Further, the influence of udder traits on variation in lamb weaning weight was explored. Measured udder and teat size traits were estimated to have moderate to high heritabilities (0.32 (0.09) to 0.56 (0.10)), while the heritabilities of visually scored traits were lower (0.09 (0.05) to 0.17 (0.07)). Measured traits were highly correlated genetically with their equivalent visually scored traits. The odds ratio of mortality for lambs born to ewes with unsound versus sound udders was 1.54 (95 %CI 1.1–2.2, P < 0.05). The odds ratio of lamb mortality from starvation compared to all other causes of death for lambs born to ewes with unsound versus sound udders was 4.62 (95 %CI 2.4–8.9, P < 0.001). Dam udder and teat traits collectively contributed 8 % of the variation in lamb weaning weight observed. Results suggest that targeting optimal ewe udder and teat characteristics in sheep breeding programs has the potential to significantly improve lamb survival and growth in extensive production systems.

Udder, teat, and milk vein measurements of Indian dromedary camel and its relationship with milkability traits.

The economic viability of the camel in the current scenario can be ensured by improving its dairy potential. The study on the udder and teat characteristics of dromedary camel and understanding its relationship with milk yield and milkability can be of great value in establishing camel as a dairy animal. The present study was conducted on 45 lactating she-camels of four Indian camel breeds, viz., Bikaneri, Jaisalmeri, Kachchhi, and Mewari, stationed at ICAR-NRCC Bikaner, Rajasthan, India. The udder, teat, and milk vein measurements traits, factors affecting these traits and their relationship with milkability traits, were studied in hand-milked Indian dromedary camel. The means ± S.E. of teat lengths (TL), namely, left fore (LF), left rear (LR), right fore (RF), and right rear (RR), were observed as 52.21 ± 1.66, 58.52 ± 2.11, 50.13 ± 1.74, and 54.37 ± 1.82mm, respectively. The means ± S.E. of teat diameter (TD), namely, left fore, left rear, right fore, and right rear teat diameters, were observed as 42.44 ± 1.60, 46.01 ± 1.68, 39.29 ± 1.31, and 45.20 ± 1.56mm, respectively. The means ± S.E for udder depth, udder length, udder height from the ground, milk vein diameter, and milk vein length were observed as 25.44 ± 0.42, 37.29 ± 0.80, 114.80 ± 0.80, 2.02 ± 0.08, and 88.70 ± 0.96cm, respectively. Udder and milk vein measurements did not differ significantly between breeds. Kachchhi breed has largest teat length and diameter. The breed differences were significant (p ≤ 0.05) for TL-LF, TL-RF, and TD-RR only. The effect of parity was non-significant on udder, teat, and milk vein measurement traits except TD-RR (p ≤ 0.05); however, second parity animals had higher values for all the studied traits except udder height from ground. Positive and highly significant (p ≤ 0.01) correlation of milk yield was observed with the majority of udder, teat, and milk vein measurements, milking time, and milk flow rate, while a negative correlation was found with udder height from ground and milk let-down time. It can be concluded that udder characteristics are influenced by various genetic and non-genetic factors and its relationship with milk yield and milkability can be used for selection and dairy management purposes.

Effect of udder type on udder traits, milk yield and some physicochemical characteristics of milk in Awassi ewes

In this study, it was aimed to determine the effects of udder type on milk yield, udder and teat traits, and some physicochemical properties of milk in 54 Awassi ewe aged 3-4 years. In this study, Type-3 udder, which was reported to be prevalent in breeded Awassi ewes. Type-4, Type-5, and Type-6 udders were not detected in ewes. The lactation period, lactation, and the daily average milk yield values were calculated as 208.33 days, 138.59 liters, and 659.49 ml, respectively. The 90th day of lactation measurements were as follows: udder circumference (44.58 ± 0.51 cm), udder width (13.20 ± 0.36 cm), udder depth (17.66 ± 0.58 cm), udder volume (881.25 ± 37.41 ml), teat length-right (3.84 ± 0.15 cm), teat length-left (3.64 ± 0.17 cm), teat diameter-right (2.07 ± 0.14 cm). The values of the physicochemical characteristics of milk generally showed an increase from the beginning to the middle periods of lactation and then decreased. In conclusion, udder type had no significant effect on the lactation period, milk yield, udder and teat characteristics and the physicochemical properties of milk in Awassi ewes. New studies are required in the determination of the yield and other characteristics of ewes in Turkey.

Study of milkability and associated factors in hand milked Indian Dromedary Camel

Development of camel as a dairy animal and establishment of commercially viable camel dairy necessitates its evaluation for milkability. Four Indian dromedary camel breeds namely Bikaneri, Jaisalmeri, Kachchhi and Mewari under hand milking management were evaluated for milkability and associated factors in the present study. The mean milk let-down time, milking time and milk flow rate observed was 48.19 s (20.00–129.60 s), 2.66 min(0.87–5.48 min), 1.23 kg/min (0.20–4.40 kg/min), respectively. The effect of breed was highly significant (p < 0.01) on milk let-down time and milking time and significant (p < 0.05) on milk flow rate. The first parity animals took more time for milk let-down compared to higher parity animals. Milking time and milk flow rate were significantly affected (p < 0.01) by lactation stage and milk yield. The milking time showed declining trend with progression of lactation. Longer milking time was observed in early lactation. Among the four breeds faster milked let-down was achieved in Kachchhi breed. Milk flow rate was maximum in Bikaneri breed. Effect of milkers, teat length and teat diameter was non-significant on milking time and milk flow rate. Average morning, evening and daily milk yield was 3.24, 1.99 and 5.23 kg, respectively. The milk yield differed significantly (p < 0.01) between breeds. The Kachchhi breed recorded highest daily milk production among four breeds. Average teat length and teat diameter was 61.40 mm (29.20–91.90 mm) and 36.42 mm (19.77–55.41 mm), respectively. The teat measurements differed significantly between breeds. The milking time (MT), milk yield (MY1), teat length (ATL) and teat diameter (ATD) were positively correlated with each other. However milk-let down time (MLDT) has non-significant and low correlation (r= −0.097 - 0.010) with MY1, MT, ATL and ATD. MY1 has positive and significant correlation with MT (r = 0.832), ATL (r = 0.604) and ATD (r = 0.494). It can be concluded that milkability parameters are influenced by breed, parity and milk yield of the animals. Positive correlation exists between milk yield, milking time, milk flow rate and teat measurements. Due consideration should be given to the factors like breed, parity, milk yield and teat characteristics for selection of camel with superior milkability and dairy potential.

Relationships among intramammary health, udder and teat characteristics, and productivity of extensively managed ewes.

Mastitis is an economically important disease and its subclinical state is difficult to diagnose, which makes mitigation more challenging. The objectives of this study were to screen clinically healthy ewes in order to 1) identify cultivable microbial species in milk, 2) evaluate somatic cell count (SCC) thresholds associated with intramammary infection, and 3) estimate relationships between udder and teat morphometric traits, SCC, and ewe productivity. Milk was collected from two flocks in early (<5 d) and peak (30 to 45 d) lactation to quantify SCC (n = 530) and numerate cultivable microbial species by culture-based isolation followed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS; n = 243) identification. Within flock and lactation stage, 11% to 74% (mean = 36%) of samples were culture positive. More than 50 unique identifications were classified by MALDI-TOF MS analysis, and Bacillus licheniformis (18% to 27%), Micrococcus flavus (25%), Bacillus amyloliquefaciens (7% to 18%), and Staphylococcus epidermidis (26%) were among the most common within flock and across lactation stage. Optimum SCC thresholds to identify culture-positive samples ranged from 175 × 103 to 1,675 × 103 cells/mL. Ewe productivity was assessed as total 120-d adjusted litter weight (LW120) and analyzed within flock with breed, parity, year, and the linear covariate of log10 SCC (LSCC) at early or peak lactation. Although dependent on lactation stage and year, each 1-unit increase in LSCC (e.g., an increase in SCC from 100 × 103 to 1,000 × 103 cells/mL) was predicted to decrease LW120 between 9.5 and 16.1 kg when significant. Udder and teat traits included udder circumference, teat length, teat placement, and degree of separation of the udder halves. Correlations between traits were generally low to moderate within and across lactation stage and most were not consistently predictive of ewe LSCC. Overall, the frequencies of bacteria-positive milk samples indicated that subclinical mastitis (SCM) is common in these flocks and can impact ewe productivity. Therefore, future research is warranted to investigate pathways and timing of microbial invasion, genomic regions associated with susceptibility, and husbandry to mitigate the impact of SCM in extensively managed ewes.

Genetic parameters of weeping teats in Italian Saanen and Alpine dairy goats and their relationship with milk production and somatic cell score

This paper reports a quantitative genetics analysis of weeping teats (WT), an abnormality of the mammary gland in goats. Weeping teats are characterized by milk oozing out of the teat or by the presence of multiple cysts near its base. This abnormality has been routinely recorded in Italian Alpine and Saanen goats since 2000 using a score of 0 or 1 (0 = defect not present, 1 = defect present). No information is available on the genetic background of WT or its relationship with production or other udder-related traits. Data obtained by the Italian National Sheep and Goat Breeders Association (Rome, Italy) were used to estimate both heritability of WT and its genetic correlation with milk yield, somatic cell score, and udder traits. The final data set used in the analysis included 2,178 Saanen and 2,309 Alpine primiparous goats kidding from 2009 to 2014. The pedigree data included 7,333 Saanen and 7,421 Alpines, respectively. A threshold-linear multivariate animal model was used to estimate variance and covariance components. A genealogical data analysis was also implemented, including genealogical data completeness, inbreeding, and identification of possible most recent common ancestors. On average, around 4 and 13% of primiparous Saanen and Alpine females kidding from 2009 to 2014 showed mammary gland abnormality, respectively. Weeping teats heritability was 0.27 and 0.26 for Saanen and Alpine, respectively. Genetic correlations between milk production or somatic cell score ranged from -0.16 in Saanen to 0.43 in Alpine, but the standard error of the estimates was very large. Positive genetic correlations were observed among WT and teat characteristics in both Saanen and Alpine. The average inbreeding of abnormality carriers was 2.4 and 5.1 for Saanen and Alpine, respectively. The genealogical data analysis identified 4 common ancestors of affected does in Saanen and 2 in Alpine. These results indicate that WT have a possible genetic background. A genome-wide association study might help in understanding the polygenic or monogenic determination of this abnormality.

Teat characteristics in relation to animal temperament during milking in buffaloes, and comparison of buffalo and cow teat morphology

This study aimed to examine the teat characteristics in relation to the animal temperament during milking in the Anatolian buffaloes using ultrasonographic, histomorphological and immunohistochemical methods. The teat canal length (TCL), teat wall thickness (TWT), teat cisternal diameter (TCD), teat diameter (TD), teat length (TL), and teat circumference (TC) values in docile (n=5) and nervous (n=7) buffaloes were measured at the 0th,3rd and 6th minute of stimulation. In additional experiments, comparative histomorphology and immunohistochemical examinations of buffalo (n=7) and cow teats (n=8) were performed. It was determined that post-stimulation mean TCL values were significantly higher in nervous buffaloes than those of teats in docile buffaloes (p<.05). A significant positive correlation between TCD and TD, TL and TC in both docile and nervous buffaloes was noted (p<.05). Unlike nervous buffaloes where only 3/14 teat canals were open by 3rd minute of milking stimulation, almost all (9/10) teat canals were observed opened in docile buffaloes. There were fewer muscle but more collagen bundles in buffalo teats compared with cow teats. It seems that temperament of animal during milking effects the milking efficiency, and in nervous buffaloes, probably the stimulation alone may not be sufficient for opening of the teat canal and hence achieve complete milking.

Automated gradual reduction of milk yield before dry-off: Effects on udder health, involution and inner teat morphology

Lowering milk production of high yielding dairy cows before dry-off may be beneficial for both physical health and welfare of the cow. Extending the milking intervals as well as restricting energy intake are the commonly used approaches to decrease milk secretion, but are mostly accompanied by adverse side effects. Our objective was to elaborate a new technique for reducing milk production taking the natural process of weaning into account, i.e. the abatement of the calf`s milk removal when shifting its diet from milk towards solid feed. We tested a software module by which the degree of udder emptying can be gradually decreased through automated early removal of the milking clusters over 10.4 ± 1.8 days on 26 Holstein cows that were close to dry-off and free of mastitis (SCC < 100,000 cells/mL and negative bacteriology in quarter milk samples). Milk yield was compared to 30 conventionally milked control cows, which had the same initial milk yields and fulfilled the same udder health criteria. After the period of incomplete milking, milk production immediately before dry-off was 35.3 ± 12.9% less in the experimental cows compared to the control cows. As expected, the duration of milking decreased with time of incomplete milking. Neither SCC nor bacteriology findings were altered by leaving residual milk in the udder. Ultrasonographic investigation of pre- and post-milking teat characteristics showed that all traits of inner teat morphology except teat end width were less changed through the incomplete milking process when compared to the changes occurring in the conventionally milked control cows (differences in changes ranged from - 2.0% for teat width to - 27.9% for the distal teat canal`s surface). These findings suggest that the mechanical strain on the teat was considerably decreased with termination of the milking process before udders were completely emptied. After several days of incomplete milking, the perimeter and the surface of the distal teat canal of the experimental teats were even smaller before attachment of the clusters when compared to the pre-milking values of the control teats, which might reflect a strengthening of the teat canals` functional defense mechanisms against the invasion of potential pathogens. Assessments in the following lactation showed that neither milk yield nor udder health were impeded by the targeted automated reduction of milk production before dry-off. The software module tested herein thus provides an effective tool for facilitating the dry-off process.

Bottle-feeding an infant feeding modality: An integrative literature review.

Bottle‐feeding is an infant feeding modality that has been in existence since ancient times, and currently, a significant number of infants are being fed via a bottle with either breastmilk or formula. Although research on bottle‐feeding has continued, it exists in fragmented, often small studies that focus on singular aspects of feeding an infant using a bottle, with limited information on the bottle‐feeding act. Systems theory was the approach used to define the act of bottle‐feeding and identify the parts within this act. Health databases were searched using MeSH terms. A summary of the studies are included. The findings of this review revealed that healthy term bottle‐feeding infants use similar tongue and jaw movements, can create suction and sequentially use teat compression to obtain milk, with minimal differences in oxygen saturation and SSB patterns, when compared with breastfeeding infants. Bottle and teat characteristics were revealed to affect infant feeding and milk intake. An infant's milk intake during feeding was shown to have a strong association with the interaction between the infant and parent/caregiver. With the issue of who controls the feed, mother or infant, likely to affect an infant's ability to self‐regulate their milk intake. Redefining bottle‐feeding as a holistic system identifies the interrelationship of the various parts which will improve the understanding of the reciprocal nature of infant feeding. To optimize bottle‐feeding outcomes, further research is required on parents' and health professionals' knowledge and understanding of the parts within the act of bottle‐feeding.

Ultrasonographic Evaluation of Teat Structure and Detection of Prominent Annular Folds in Brazilian Dairy Buffaloes

Udder and teat characteristics differ between buffaloes (Bubalus bubalis) and cattle (Bos taurus) and the differences are important in relation machine milk ability. Dairy buffalo milk out more slowly and are more difficult to milk than dairy cows, especially when milking machines are used. The goal of this study was to determine the ultrasonographic characteristics of udder and teat morphology in dairy buffaloes in Brazil, a country with a relatively recent history of buffalo farming. External assessment of the udder type and ultrasonography of the teat were done in 63 purebred Murrah and Mediterranian ´ Murrah dairy buffalo cows on three farms with different management systems. Udder types differed among farms; the rear-heavy udder type was most prevalent on two farms and the ball-shaped type occurred frequently on the third farm. Ultrasonographic measurements of the teat were made on one farm and showed correlations between the width of the teat tip and teat canal length, between the width of the teat tip and teat wall thickness and between the width of the teat tip and teat length. During the ultrasonographic examination of the teat, hyperechogenic membrane-like structures in the region of the annular folds, referred to as prominent annular folds (pAFs), were detected in at least one teat in 98 % of all buffaloes. These folds caused narrowing of the lumen between the teat cistern and gland cistern, but their physiological function and relevance concerning machine milk ability remain unclear. Further studies are needed to evaluate the effect of prominent annular folds on milk flow characteristics during mechanical milking in dairy buffaloes.

An observational study investigating the association of ultrasonographically assessed machine milking-induced changes in teat condition and teat-end shape in dairy cows

Mechanical forces during machine milking induce changes in teat condition which can be differentiated into short-term and long-term changes. Machine milking-induced short-term changes in teat condition (STC) are defined as tissue responses to a single milking and have been associated with the risk of new intramammary infection. Albeit, their association with teat characteristics, such as teat-end shape, has not been investigated by rigorous methods. The primary objective was to determine the association of STC, as measured by ultrasonography, with teat-end shape. The second objective was to describe possible differences in the recovery time of teat tissue after machine milking among teats with different teat-end shapes. Holstein cows (n=128) were enrolled in an observational study, housed in free-stall pens with sand bedding and milked three times a day. Ultrasonography of the left front and right hind teat was performed after teat preparation before milking (t−1), immediately after milking (t0) and 1, 3, 5 and 7 h after milking (t1, t3, t5, t7). The teat tissue parameters measured from ultrasound scans were teat canal length, teat-end diameter, teat-end diameter at the midpoint between the distal and proximal end of the teat canal, teat wall thickness, and teat cistern width. Teat-end shape was assessed visually and classified into three categories: pointed, flat and round. Multivariable linear regression analyses showed differences in the relative change of teat tissue parameters (compared with t−1) at t0 among teats with different teat-end shapes, with most parameters showing the largest change for round teats. The premilking values were reached (recovery time) after 7 h in teats with a pointed teat-end shape, whereas recovery time was greater than 7 h in teats with flat and round teat-end shapes. Under the same liner and milking machine conditions, teats with a round teat-end shape had the most severe short-term changes. The results of this observational study indicated that teat-end shape may be one of the factors that contribute to the severity of STC.

New mastitis phenotypes suitable for genomic selection in meat sheep and their genetic relationships with udder conformation and lamb live weights

Mastitis can prove expensive in sheep reared for meat production due to costs associated with treatment methods, poor lamb growth and premature culling of ewes. The most commonly used method to detect mastitis, in dairy systems, is somatic cell counts. However, in many meat-producing sheep flocks ewes are not routinely handled, thus regular milk sampling is not always possible. It is, therefore, worthwhile to investigate alternative phenotypes, such as those associated with udder conformation and methods of evaluating somatic cell counts in the milk, such as the California Mastitis Test. The main objectives of this study were therefore: (a) to estimate genetic parameters of traits relating to mastitis and udder conformation in a meat sheep breed; (b) estimate the level of association between somatic cell counts and the California Mastitis Test and (c) assess the relationships between mastitis and both udder conformation and lamb live weights. Data were collected from Texel ewes based on 29 flocks, throughout the UK, during 2015 and 2016. The ewes were scored twice each year, at mid- and late-lactation. Eight different conformation traits, relating to udder and teat characteristics, and milk samples were recorded. The data set comprised of data available for 2957 ewes. The pedigree file used contained sire and dam information for 31 775 individuals. The animal models used fitted relevant fixed and random effects. Heritability estimates for traits relating to mastitis (somatic cell score and the California Mastitis Test), ranged from 0.08 to 0.11 and 0.07 to 0.11, respectively. High genetic correlations were observed between somatic cell score and the California Mastitis Test (0.76 to 0.98), indicating the California Mastitis Test to be worthwhile for assessing infection levels, particularly at mid-lactation. The strongest correlations observed between the mastitis traits and the udder conformation traits were associated with udder depth (0.61 to 0.75) also at mid-lactation. Negative phenotypic correlations were estimated between mastitis and the weight of lamb reared by the ewe (−0.15 to −0.23), suggesting that lamb weights fell as infection levels rose. Genetic correlations were not significantly different from zero. Reducing mastitis will lead to improvements in flock productivity and the health and welfare of the animals. It will also improve the efficiency of production and the resilience to disease challenge. The economic benefits, therefore, of these results combined could be substantial not only in this breed but also in the overall meat sheep industry.

Udder and teat characteristics of Surti buffaloes maintained under farm and field conditions

Udder and teat characteristics of Surti buffaloes maintained under farm and field conditions

Udder and Teat Characteristics of Surti Buffaloes Maintained Under Farm and Field Conditions

Udder and Teat Characteristics of Surti Buffaloes Maintained Under Farm and Field Conditions

Anatomical characteristics of teats and premilking bacterial counts of teat skin swabs of primiparous cows exposed to different types of bedding

Bacterial populations of teat skin are associated with risk of intramammary infection and may be influenced by anatomical characteristics of teats. The objective of this study was to evaluate associations of selected anatomical characteristics of teats with bacterial counts of teat skin of cows exposed to different types of bedding. Primarily primiparous Holstein cows (n = 128) were randomly allocated to 4 pens within a single barn. Each pen contained 1 type of bedding [new sand (NES), recycled sand (RS), deep-bedded manure solids (DBMS), and shallow-bedded manure solids over foam core mattresses (SBMS)]. During a single farm visit udders (n = 112) were scored for hygiene and 1 front (n = 112) and 1 rear teat (n = 111) of each enrolled cow were scored for hyperkeratosis (HK). Teat length, teat barrel diameter, and teat apex diameter were measured and teat skin swabs were systematically collected for microbiological analysis. Linear type evaluation data for udders of each cow were retrieved for each cow. Teat position (front or rear) was associated with occurrence of clinical mastitis during the 12 mo before the farm visit and more cases occurred in front quarters. The proportion of udders that were classified as clean (score 1 or 2) was 68, 82, 54, and 95% for cows housed in pens containing NES, RS, SBMS, and DBMS, respectively. No association was found between HK score and teat position and no association was found between HK score and teat skin bacterial count. Bacterial counts of teat skin swabs from front teats of cows in pens containing RS and SBMS were significantly less than those of rear teats of cows in pens containing DBMS or NES. Teat skin bacterial counts were significantly greater for swabs obtained from teats of cows with udder hygiene scores of 3 and 4 as compared with swabs obtained from cows with cleaner udders. Of all udder conformation traits evaluated, only narrower rear teat placement was positively associated with bacterial counts on teat skin.

Association of anatomical characteristics of teats with quarter-level somatic cell count

Mastitis occurs after bacteria successfully traverse the teat orifice and cause an intramammary infection. Anatomical characteristics of the teat are potential risk factors for infection. The objective of this study was to identify potential associations between anatomical characteristics of teats and quarter-level somatic cell count (QSCC) from cows on larger dairy farms in Wisconsin. Teat dimensions (length and diameter at the teat barrel and apex) were measured, and hyperkeratosis scores were assessed for 3,713 quarters of 959 cows on 9 dairy farms. The SCC of quarter milk samples obtained from those teats was determined. Multivariate models were used to determine associations of teat anatomical characteristics with QSCC. Subclinical mastitis was defined as a quarter milk sample with SCC of >150,000 cells/mL. Teat dimensions and milk components varied among farms. In the group of farms enrolled in this study, prevalence of subclinical mastitis in mammary gland quarters ranged from 13.6 to 28.9%. An interaction of teat apex diameter and quarter position (front or rear) was identified for QSCC. For both front and rear quarters, a tendency existed for narrower teat barrels to be associated with increased QSCC. However, for front quarters only, greater diameter of the teat apex was associated with increased QSCC. Teat shape (square or triangular teats) was not associated with QSCC. Milk samples obtained from teats with hyperkeratosis scores of very rough had greater QSCC compared with milk samples obtained from teats with hyperkeratosis scores of normal, smooth ring, or rough ring.

An investigation of risk factors for two successive cases of clinical mastitis in the same lactation

The objective of this study was to identify risk factors for the occurrence of two successive cases of clinical mastitis (CM). Two farms were visited monthly during 10 months. Milk samples were collected from all cases of CM that occurred during the study. Cows were observed prospectively from the beginning of the study and a case cow was defined when she experienced the second case of CM within the same lactation. For each case cow, 3 control cows matched by days in milk (DIM) were randomly selected from the cohort of cows who did not experience CM. On each visit day, a series of udder and teat characteristics were recorded during milking time: teat-end hyperkeratosis scoring, milking ease scoring, teat length and diameter, teat-to-ground distance, and udder position in relation to the hock. A total of 113 case cows and 324 control cows were used for analyses. The median time to occurrence of the first case of CM was 84 DIM and the median interval between the first and second cases of CM was 39 days. Of all second cases, 49.6% (N=55) occurred in the same mammary gland. Of these 55 cases, 29.1% had identical milk culture results from both first and second cases. Most cases of CM were caused by coliforms and environmental streptococci. Teat-to-ground distance, teat-end hyperkeratosis, udder position in relation to the hock, milking ease, parity, and milk production at the first test of lactation were individually associated with the occurrence of two successive cases of CM. Of all explanatory variables, 3 remained in the final multivariable model. The odds of two successive cases of CM were 3.7 times greater for cows who were “very easy to milk”, as compared with cows who were “difficult to milk”. Cows who had their udders below the hock, and those of parity >2 were 3.6 and 2.5 times more likely to experience two successive cases of CM, as compared with cows whose udder was positioned above the hock, and cows of parity 1, respectively. Findings of this study highlight the importance of teat and udder characteristics as risk factors for two successive cases of CM. Further investigations are needed to elucidate the role of the teat canal in preventing mastitis for modern cows that have been selected for increased milk production, shorter teats, and greater milk flow rates.

Short communication: Pre- and postmilking anatomical characteristics of teats and their associations with risk of clinical mastitis in dairy cows

The primary objective of this study was to describe and compare anatomical characteristics of teats before and after machine milking adjusted for parity and teat location (front versus rear). The second objective was to determine if selected milking and anatomical characteristics of teats were associated with occurrence of clinical mastitis. To address objective 1, a cross-sectional study was done to describe and compare teat dimensions before and after milking (n=1,751 teats from 445 cows). To fulfill objective 2, a case-control study was performed. Quarters having their first case of clinical mastitis in the current lactation from 2 mo before to 2 mo after the day the teats were measured were selected as cases (n=47), provided no other quarters from that cow were affected by clinical mastitis at that time. Three controls (n=141) were matched with each case; these were selected from quarters that did not experience any case of clinical mastitis during their current lactation. A conditional logistic regression model was used to determine associations between teat dimensions and occurrence of clinical mastitis. Primiparous and multiparous Holstein cows were enrolled in both studies. As compared with premilking dimensions, postmilking teats were longer and narrower at the barrel and the apex. Significant interactions between teat position and parity were identified for premilking teat length and diameter of the teat barrel. Premilking, teats were longer and wider with increasing parity. Front teats were longer and wider than rear teats premilking. Also during premilking, differences between the front and rear teat were less at increasing parity. Teat apex diameter was greater for premilking teats of cows in parity ≥3 and the apexes of front teats were wider than those of rear teats. Teats enrolled in the case-control study had twice as many clinical mastitis cases in front quarters compared with rear quarters. Premilking diameter of the teat apex was positively associated with risk of clinical mastitis (odds ratio=1.20 per 1-mm increase in the diameter of the apex of the teat, 95% confidence interval=1.05-1.37). Milking machine-related changes in teat dimensions had no association with occurrence of clinical mastitis.

Some production traits and phenotypic relationships betweenudder and production traits of Hair goats

The study was conducted to determine the production characteristics and to find out the phenotypic relationships between udder and milk production traits in Hair goats. A total of 403 Hair Goats under extensive conditions of Çine town of Aydin province of Turkey were constituted the animal material of the study. The live weights of all goats were recorded just before breeding season. Milk was measured in every month according to the basis of morning or evening milking in a day to estimation of milk yields. Live weights of kids were recorded monthly intervals. Measurements for udder characteristics were determined for two times at 30th and at 180th of the lactation period. Average lactation length, lactation milk yield and daily milk yield of goats were 192.4 days, 139.1 kg and 0.7 kg, respectively. The live weights at birth, 30th, 60th, 90th and 120th days of goat kids were 3.1, 8.6, 13.9, 19.1 and 24.5 kg, respectively. Mean values of withers height, body length and live weight of goats were measured as 73.2 cm, 71.3 cm and 54.5 kg, respectively. Udder and teat characteristics of goats were found positively correlated with milk production characteristics both 30th and 180th days of the lactation period. It can be concluded that Hair goats in extensive conditions had a substantial level of milk yield and their kids had sufficient levels of live weight gains. Furthermore, the udder measurements at the beginning of the lactation could be used for identifying the differences among does.